Order of the Ministry of Labour and Social Protection of the Russian Federation No. 922n of 17 December 2020
Unofficial translation. Only the Russian original published in the official sources of the Russian Federation has legal force. This translation is provided for reference and does not replace the official document.
1. The Labour Protection Rules for Diving Work (hereinafter - the Rules) establish state regulatory labour protection requirements and regulate the procedure for the actions of the employer and the employee in organising and carrying out diving work. The Rules apply throughout the territory and on the continental shelf of the Russian Federation.
2. The requirements of the Rules are mandatory for employers - legal entities irrespective of their organisational and legal forms and natural persons (with the exception of employers - natural persons who are not individual entrepreneurs) when they organise and carry out diving work
3. Employers and their associations may establish safety standards for diving work that do not contradict the requirements of these Rules.
4. The requirements of the Rules do not apply to diving work performed by military divers in carrying out their tasks within the framework of their official duties, and to other types of work performed underwater using human labour that are performed outside employment relations and other relations directly connected with them.
5. Organisations carrying out diving work shall, in accordance with the requirements of the Rules, the operating documentation and regulatory legal acts, develop an organisation's standard of safe activity for the performance of diving work, taking into account the specific conditions of the organisation's production or official activity, labour protection instructions for employees, instructions for the operation of diving equipment and process equipment, and instructions on safe methods of descents and ways of performing diving work characteristic of the organisation.
6. When performing diving descents and carrying out diving work, divers may be exposed to the following main harmful and hazardous production factors: (a) factors that are present in all cases: 1) direct presence in an environment not adapted to sustaining life; 2) elevated pressure of the gaseous and aqueous environment; 3) pressure changes of the gaseous and aqueous environment; 4) elevated partial pressure of oxygen and inert gases; 5) elevated density of the aqueous (gaseous) environment; 6) elevated density of the breathing gas mixture; 7) absence of the technical and physiological possibility to interrupt the stay underwater. (b) factors that depend on the conditions of the diving descent, the types of diving gear and diving work: 1) elevated concentrations of carbon dioxide and harmful substances in the breathing gas mixture; 2) dynamic impact of the aqueous environment (currents and waves of the water); 3) low or high water temperature; 4) elevated noise level in the elements of the diving gear; 5) insufficient illumination and visibility at the workplace, complete absence of visibility; 6) presence of natural and man-made obstacles and hazards underwater; 7) confined and enclosed spaces; 8) elevated electrical, fire and explosion hazard; 9) contamination of the aqueous environment (chemical, bacterial, radioactive); 10) presence of dangerous representatives of marine fauna;
7. Harmful and hazardous production factors, depending on the specific conditions of production activity and the nature of the diving work performed, as well as the results of the special assessment of working conditions carried out, shall be taken into account in the risk assessment before the start of diving work. Based on the results of the risk assessment, compensating actions are determined and carried out, and measures are taken to ensure additional protection of divers, the use of protective devices, means and appliances, changing the methods of descents or ways of performing diving work, and the possibility of performing diving work.
8. The safety of diving work may be affected by the actions or inaction of the head of the organisation for which the diving work is carried out (the owner of the facility, site, area, territory or their authorised representative, the customer of the work), or of the head of an organisation located in the immediate vicinity of the place where the diving work is carried out.
9. The head of the organisation carrying out diving work, or a person authorised by them, requests in advance, in writing, from the persons specified in paragraph 9 of the Rules, information about the facility (site, area, territory) that may affect the safety of the diving work. Based on the results of the risk assessment and the taking of compensating measures, the head of the organisation carrying out diving work, or a person authorised by them, and the head of the organisation in respect of which the diving work is carried out, shall agree the actions to ensure the safe performance of the diving work.
10. The organisation carrying out diving work shall carry out its activity in accordance with the requirements of the Rules and shall have on its staff: 1) a diving station staffed with employees admitted to diving descents, in the necessary number in accordance with the norms specified in Appendices No. 1 and No. 2 to the Rules; 2) specialists admitted to supervising diving descents and supervising diving work; 3) engineering and technical personnel possessing the necessary and sufficient competence (training) corresponding to the type and nature of the forthcoming work. For descents to a depth of more than 60 m, the staffing of the diving station (group) is determined depending on the type of deep-water diving complex and the method of carrying out the descents. The organisation carrying out diving work shall possess diving equipment in the quantity necessary for the safe performance of diving work, not lower than that specified in paragraph 130 of the Rules, and in sound technical condition, owned by the organisation or held on other lawful grounds. The management system of the organisation shall include a local labour protection management system for the performance of diving work, aimed at ensuring the safe performance of diving work, the application of a risk-based approach, and ensuring the reliability and sound condition of diving equipment and the competence (training) of specialists and employees corresponding to the work performed.
11. The employer shall ensure: 1) safe conditions for the performance of diving work, proper maintenance and operation of diving equipment; 2) the functioning in the organisation of a labour protection management system (hereinafter - the LPMS); 3) monitoring of the state of working conditions at workplaces, compliance with labour protection requirements and the provision of social protection measures to employees; 4) the correct use by employees of diving gear and personal protective equipment (hereinafter - PPE), 5) training of employees in labour protection, verification of knowledge and admission to the performance of diving descents and work; 6) the identification of hazards, the assessment of risks and their management, as well as informing employees about them; 7) the development of production planning documents, process charts and other documents necessary for the organisation and safe performance of diving work in the organisation; 8) the performance of diving work in accordance with the requirements of these Rules, regulatory legal acts in the field of labour protection, industrial safety and other regulatory legal acts. The employer may establish additional safety requirements that improve the working conditions of employees, the safety of the organisation and the performance of diving work.
12. The organisation carrying out diving work shall ensure compliance with the requirements of labour protection, industrial and fire safety, environmental protection and other lawful requirements established by the owner of the facility.
13. The employer, depending on the specifics of its activity and on the basis of the assessment of the level of occupational risk, may: 1) establish additional safety requirements that do not contradict the Rules. Labour protection requirements shall be contained in the relevant labour protection instructions and communicated to the employee in the form of orders, instructions and briefings; 2) to monitor the safe performance of work, use instruments, devices, equipment and (or) a set (system) of instruments, devices and equipment that provide remote video, audio or other recording of the work performance processes.
14. Document management in the field of labour protection may be maintained in electronic form using an electronic signature or any other method that allows the identity of the employee to be identified, in accordance with the legislation of the Russian Federation.
15. The employer shall, before the start of diving work, organise technical, technological and organisational actions: 1) technical and technological actions, comprising the development and execution of production planning documents, carried out at workplaces with geographically changing work zones (hereinafter - non-stationary workplaces); the development and approval of process charts for the performance of work; the posting of warning and mandatory signals (signs, posters); the fencing of the place where work is carried out; the use of serviceable diving equipment corresponding to the nature of the diving work performed; the use of collective and personal protective means; 2) organisational actions, comprising the appointment of persons responsible for the organisation and safe performance of diving work, for the issuance of the permit to work; for drawing up the list (plan) of actions in the event of an off-nominal and emergency situation, as well as persons carrying out the technical maintenance and periodic inspections (repairs) of diving equipment.
16. Production planning documents shall include: 1) the time frames and the resources involved; 2) the stages of carrying out the work; 3) the governing documents used during the work; 4) the methods of performing diving descents and the ways of performing the work (tasks); 5) actions to ensure the labour protection of divers, taking into account the conditions and nature of the work; 6) the conditions under which diving descents and work shall be suspended or prohibited, or other restrictions on the work; 7) the procedure for obtaining permission to start work; 8) the results of the risk assessment, ways to prevent the risks and (or) compensating actions; 9) the regulations for monitoring the safety of diving work; 10) actions in the event of off-nominal and emergency situations; 11) the organisation of interaction between all participants in the diving work (communication or other means of communication). When developing production planning documents for the performance of diving work on the open sea, the safety requirements of international standards, norms and practices may be taken into account, provided that they do not contradict state standards and do not lower the requirements for the safety of performing the work.
17. Depending on the type and nature of the work, various production planning documents are developed, which include: a plan or design for the performance of work; survey or inspection programmes; work organisation or construction designs, plans of diving work or descents, a work assignment order. When carrying out diving work from stationary workplaces, the production planning document is the work assignment order.
18. It shall not be permitted to change the set of actions provided for by the production planning documents that ensure the safety of diving work. Changes to the production planning documents are possible only after a risk assessment has been carried out and provided that the changes made do not lead to a reduction in the level of safety during diving work or to a deterioration of working conditions.
19. Upon the discovery of violations of the actions ensuring the safety of diving work provided for by the production planning documents, or upon the identification of other circumstances threatening the safety of divers, the diving work shall be immediately suspended by the person in charge of the diving work. Only after the discovered violations have been eliminated may divers be admitted to work again. When carrying out diving work in international waters, in the territorial waters of foreign states, on the territory and continental shelf of the Russian Federation with the application of international or interstate standards, as well as during joint work with foreign organisations, the safety norms shall be agreed before the start of work. The requirements for the safety of diving work shall not be lower than those adopted on the territory of the Russian Federation. In the event of a discrepancy in the requirements for the safety of diving work, the right of extraterritoriality of a vessel flying the flag of the Russian Federation shall be exercised.
20. Before the start of diving work, the personnel of the diving station shall be familiarised with the production planning documents and process charts and informed of their personal responsibility for the consequences caused by deviation from the safe methods and techniques of the work performed by them.
21. The employer shall approve a list of work performed under a permit to work (hereinafter - the List). The List shall include diving work performed at hazardous production facilities and other work at the discretion of the employer.
22. In exceptional cases (the prevention of an accident, the elimination of a threat to the lives of employees, the elimination of the consequences of accidents and natural disasters, training diving descents), diving work may be started without drawing up a permit to work under the supervision of employees appointed by the employer as responsible for the safe organisation and performance of diving work (the person in charge of the diving work, the person in charge of the diving descent). If this work is performed for more than 24 hours, the permit to work shall be drawn up without fail.
23. The permit to work determines the place where diving work is carried out, its content, the conditions for carrying out the diving work, the time of the start and end of the work, the composition of the diving station performing the work, and the persons responsible during the performance of this work. If diving work is carried out simultaneously with other types of work requiring the drawing up of a permit to work, a single permit to work may be drawn up, including in it information on the performance of diving work and the appointment of persons responsible for the safe performance of diving work.
Upon completion of the work and signing, one copy is handed over to the head of the facility (the representative of the customer), and the second remains with the organisation carrying out the diving work.
24. In cases where the drawing up of a permit to work is not required, a work assignment order for the performance of diving work shall be drawn up. The recommended template is provided in Appendix No. 5 to the Rules.
25. The work assignment order specifies the customer (the owner of the facility), the persons in charge of the diving work and descents, the diving complement of the station (group), the person providing first aid to a diver in the event of illnesses and injuries connected with the professional activity of divers, or providing medical support, the place and volumes of diving work, the time of the start and end of the work, the personnel and technical means to support the work; the main instructions on labour safety in the performance of this work are given. A list of the hazards identified and the results of the risk assessment are attached to the work assignment order.
26. Upon receiving the work assignment order directly from the administration of the enterprise, the person in charge of the diving work shall verify: 1) the correctness and sufficiency of the safety measures envisaged, corresponding to the conditions of the work, the place and nature of the work; 2) the correspondence of the qualifications of the person in charge of the diving descents and of the person providing first aid in the event of illnesses and injuries connected with the professional activity of divers, or medical support, as well as of the diving and auxiliary personnel.
27. The work assignment order is drawn up for each object of work or a specific type of work until its completion. For short-term and simple diving work in terms of volume, performed without designs, a work assignment order may be issued for the entire period of its performance.
28. When two or more diving stations work at a facility, the work assignment order is issued to each diving station separately, indicating the specific types of diving work performed.
29. Before the start of diving work, the person in charge of the diving work shall conduct a briefing for the diving and support personnel in accordance with the work assignment order and hands it over personally to the person in charge of the diving descents, whereupon a mutual signature is made in the work assignment order. In cases where the performance of diving work is of a one-off nature, the work assignment order may be transferred to the person in charge of the diving work by email. In this case, the work assignment order is filled in in 2 copies: one copy is filled in by the administration of the enterprise, and the other by the person in charge of the diving work receiving it by email, indicating the details of the transferring party and their own.
30. Upon completion of the work or expiry of the term of validity of the work assignment order, the line "Note on completion of the task" is filled in, executed with the signatures of the persons in charge of the diving work and the diving descents. In the event of the absence of one of the signatures in this line, the work under the work assignment order is considered not performed.
31. The agreement of the work assignment order with the responsible representative of the customer (the owner of the facility) is carried out in the case where the production activity (of the vessel, hydraulic engineering structure, facility) may affect the safety of carrying out diving work.
32. When performing diving work in the protection zones of structures or utilities, the permit to work is issued provided there is a written permission from the owner of that structure or utility.
33. For the organisation of the safe performance of diving work, the following are appointed: 1) the composition of the diving group (diving station); 2) the persons in charge of the diving descents; 3) the persons in charge of the diving work; 4) the person responsible for providing first aid to divers in the event of illnesses and injuries connected with the professional activity of divers. Where necessary and in the cases provided for by the Rules and other regulatory legal acts, the following are appointed: 1) the person responsible for the medical support of diving descents; 2) the responsible performing authority (executor) of the diving work from among specialists or highly qualified workers (the person responsible for the monitoring and observance of labour protection and safety requirements during diving work at the facility); 3) the person responsible for material and technical support. 4) engineering and technical personnel from among specialists engaged in the diving work. 5) auxiliary personnel from among employees not of the diving complement (persons admitted to servicing specific types of diving equipment, means of supporting diving descents, process equipment or supporting diving descents). The above officials shall, in the cases provided for by the Rules and other regulatory legal acts, undergo the relevant special training. Employees specified in sub-clauses 7 - 9 of this paragraph of the Rules may be appointed without special training.
34. For the organisation of the safe performance of diving work carried out with the drawing up of a permit to work at a separate facility (in the conditions of an expedition, a business trip, from a vessel not belonging to the organisation carrying out the diving work), officials having the right to issue the permit to work are additionally appointed from among managers and specialists.
35. The appointment of employees performing diving work at separate facilities is carried out by order of the employer.
36. The permit to work is issued for the period necessary to perform the given volume of work, indicating the exact time of the start and end of the diving work. The permit to work may be extended once for a period of no more than 15 calendar days from the day of its extension. During breaks in the work, the permit to work remains valid. If, in the course of the work, hazardous production factors and harmful working conditions not provided for by the permit to work arise, then, by decision of the responsible performing authority (the person in charge of the diving work), the work is stopped, the permit to work is cancelled, and the work is resumed after the issuance of a new permit to work. The permit to work may be extended by the employee who issued it or by another employee having the right to issue the permit to work.
37. Permits to work under which the work has been fully completed shall be kept for 30 days, after which they may be destroyed. If, during the performance of work under permits to work, industrial accidents occurred, then these permits to work shall be kept in the archive of the organisation together with the materials of the investigation of the industrial accident. A record of the work under permits to work is kept in the log of work under a permit to work.
38. Upon the discovery of violations of the actions ensuring the safety of diving work provided for by the permit to work and the production planning documents, or upon the identification of other circumstances threatening the safety of divers, it shall be prohibited to carry out diving descents. After the discovered violations have been eliminated, divers may be admitted to work again.
39. The composition of the diving station may be changed by the employee who issued the permit to work or by another employee having the right to issue the permit to work for the performance of diving work. Instructions on changes to the composition of the diving station may be transmitted by telephone communication, radio communication or personally to the person in charge of the diving work or the responsible performing authority, who records in the permit to work the surname and initials of the employee who gave the instruction on the change to the composition of the diving station. The person in charge of the diving descents shall, during the briefing, communicate to the employee information on the actions provided for by the permit to work. Upon replacement of the person in charge of the diving work, the responsible performing authority or the person in charge of the diving descents, upon a change of more than half of the composition of the diving station, or upon a change in the conditions and nature of the work, the permit to work is cancelled, and the work is resumed after the issuance of a new permit to work.
40. After the completion of the work, the person in charge of the diving work shall record in the permit to work the full completion of the work and hand over the permit to work to the employee who issued it. When carrying out diving work in two or more shifts, the repeated admission and the admission of other shifts is carried out by the person in charge of the diving work or the responsible performing authority. Upon the resumption of work, the person in charge of the diving descents shall make sure of the safety of carrying it out. The responsible official of the structure (the owner of the facility) shall make sure of the completion of the diving work and only after that allow the operation of the structure (facility).
41. Actions to prepare for the response in the event of off-nominal and emergency situations shall, depending on the nature, type, volume and place of the forthcoming diving work and the conditions of carrying it out, be developed in the form of a separate document (plan) or provided for in a separate section in the production planning documents.
42. Actions to prepare for the situation of the occurrence of off-nominal and emergency situations shall contain a list of the off-nominal and emergency situations characteristic of the forthcoming diving work, measures for their compensation and actions in the event of their occurrence, taking into account the conditions in which the work is carried out, the experience of carrying out similar or comparable work and the features of the facility at which it is carried out. The results of the work on the identification of hazards and the assessment of risks shall be the basis for the planning of the above actions. The plan may be a standard one, permanently in force during the performance of diving work at stationary workplaces and at facilities with a permanent location of deployment.
43. Preconditions and incidents, off-nominal and emergency situations, accidents and industrial accidents shall be subject to recording, analysis and (or) investigation, for the purpose of the comprehensive study of the circumstances and causes giving rise to them, the uncovering of deficiencies and the development of actions for their further prevention. A system for notification of preconditions and incidents, off-nominal and emergency situations, accidents and industrial accidents shall function in the organisation. Preconditions, incidents, off-nominal and emergency situations that have occurred in the course of the performance of diving work and have resulted in injury or death shall be subject to internal proceedings or investigation and recording in the organisation. The causes and circumstances shall be taken into account in the documents of the labour protection management system for diving work (hereinafter - the LPMS) and in the risk assessment documents.
44. After the occurrence of an accident or industrial accident, the work shall be stopped and the situation at the diving station preserved until the arrival of officials, provided that this does not pose a danger to the life and health of people and does not lead to an accident, and also does not disrupt the production process. The procedure for the investigation, recording and reporting of industrial accidents and accidents that have resulted in injuries or death is carried out in accordance with the legislation of the Russian Federation.
45. Persons who have reached the age of 18 are admitted to direct work underwater (in conditions of elevated pressure of the surrounding environment). Employees performing diving work shall undergo mandatory preliminary (upon entry to employment) and periodic medical examinations. Employees performing diving work shall have qualifications corresponding to the nature of the work performed. The nature of diving work depending on the type of professional activity is specified in Appendix No. 6 to the Rules.
46. Employees are admitted to diving work annually by order of the employer after the following have been conducted: (a) labour protection briefings and on-the-job traineeship; (b) verification of knowledge of labour protection requirements and of training in safe methods and techniques of performing diving work. Periodic verification of knowledge of labour protection requirements and of training in safe methods and techniques of performing diving work is carried out at least once every 12 months.
47. The employer (or a person authorised by them) shall, before the start of diving work, organise additional training in labour protection and in safe methods and techniques of performing diving work for employees: (a) admitted to diving work for the first time; (b) admitted to diving work the conditions or nature of which differ from the work that the employees previously performed, where the employees have not undergone the relevant training; (c) having a break in work of more than one year.
48. Information on the completion of training and on the assignment and (or) upgrading of the qualifications of the diving complement is entered in the diver's personal record book, drawn up during the initial training.
49. Admission to the performance of work underwater, to the supervision of diving descents, to the supervision of diving work and to their support is carried out by order of the head of the organisation on the basis of the protocol of the verification of knowledge by the commission of the organisation.
50. The procedure for the verification of knowledge and the admission of an employee to independent work is determined by the administrative documents of the organisation and shall initially provide for the performance of the following procedures: (a) verification of the presence of a document confirming the qualification of the employee; (b) verification of the presence of a document confirming the completion of a medical examination; (b) a briefing before admission to diving work; (c) the conduct, under the supervision of a responsible person and/or an experienced employee (mentor), of a traineeship (theoretical, practical or adaptation training), providing for the study of: instructions, diagrams, the layout of equipment, the actual arrangement of instruments and controls, monitoring of the operation of the equipment, methods and frequency of its checking; safe methods and techniques of performing diving work, the procedure for the technical inspection and repair of diving equipment and its preparation for work; (d) verification of knowledge of the requirements of the governing documents in the field of the performance of diving work, the standards and instructions of the organisation, and safe methods and techniques of performing diving work; (e) the conduct of a traineeship with independent performance of work under the observation of a mentor; (f) admission to independent work. The admission of an employee to participate in the conduct of actions connected with direct participation in the performance of diving work is documented in the procedure established by the administrative documents of the organisation. The duration of the traineeship and (or) practical training is established depending on the conditions and nature of the diving work in the specific conditions of production, the organisation, the type of work and the complexity of the process, the level of qualification and the presence of work experience of the employee being admitted.
51. For the resolution of questions concerning the admission of persons participating in the performance of diving work, a commission for the verification of the knowledge of personnel (participating in the performance of diving work) shall be established. The commission shall be established by an order, which determines the composition of the commission and the number of its members. At the same time, at least 3 persons from among the members included in the composition of the commission shall participate in carrying out the verification of the knowledge of a specific employee. The commission for the verification of the knowledge of personnel includes specialists responsible for the sound condition and (or) safe operation of diving equipment, as well as other specialists possessing the necessary qualifications and work experience.
52. The verification of the knowledge of personnel, in the procedure established by the administrative documents of the organisation, is carried out in the form of an interview and testing on control questions, and may also, where necessary, provide for the performance of practical tasks. The volume of the questions considered in this case shall ensure the possibility of verifying knowledge of the requirements established by the production instructions and other administrative documents, which determine the list of work forming part of the duties of the person being examined, the safe methods and techniques of performing it, as well as the procedure for actions in emergency situations. The list of the instructions in force and other documents forming part of the volume of the verification of the knowledge of personnel, for a specific structural subdivision, workplace, profession (speciality) and the work performed by the employee, is approved and updated in the event of their change in the procedure established by the administrative documents of the organisation.
53. The results of the knowledge assessment of persons involved in carrying out diving work are recorded in a protocol in accordance with the procedure established by the organisation's administrative documents. The results of the knowledge assessment of divers are recorded by an entry in the diver's personal logbook concerning admission to work underwater and (or) under elevated pressure. The form of the knowledge assessment protocol concerning admission to work is determined by the organisation's administrative documents, whereby: (a) the protocol shall be signed by all members of the commission who conducted the knowledge assessment and shall contain information about the worker who underwent it; (b) the entry in the diver's personal logbook concerning admission to work shall contain brief information about the types of work (and equipment) for the independent performance (servicing) of which the worker has been admitted; (c) after the knowledge assessment has been conducted, the worker shall be familiarised with its results against signature.
54. Commissions for admission to diving work are established in organisations carrying out diving work, in organisations engaged in educational activity relating to the vocational training, advanced training and retraining of divers, and in employers' associations of the relevant field of activity.
55. The qualifications of divers and the procedure for their conferral and maintenance shall correspond to the type of professional activity, depending on the specific conditions of the production or service activity (on the nature of the work performed), and to the regulatory legal acts in force. Qualification requirements for divers are established on the basis of the qualification characteristics in force or in professional standards, depending on the specific conditions of the production or service activity.
56. The grounds for stopping work may be: 1) failure to carry out the labour protection and diving work safety actions provided for by the production planning documents and the permit to work, disregard of the risk assessment results, a decline in the overall level of diving work safety in the course of carrying it out; 2) the issuing of commands, the setting of tasks or other causes threatening the preservation of the life and health of workers; 3) non-conformity of the actual conditions of the diving descent with the existing or established restrictions. The grounds for removing workers involved in carrying out diving descents and work may be: 1) manifestations of toxic influence (alcoholic, narcotic, medicinal) or its after-effect; 2) disturbances of the psychomotor state, inadequate (deviant) behaviour (excessive mental strain, mental agitation, manifestations of aggression or apathy); 3) the state of wellbeing (fatigue, deterioration of wellbeing during work, sudden illness); 4) violation, as well as failure to comply with, labour protection requirements at any stages of the diving descent and in the pre-descent period.
57. The safety of carrying out diving work is ensured by: 1) compliance with the requirements of the Rules and other regulatory legal acts governing matters of labour protection, health and industrial safety when carrying out diving work; 2) the rational organisation of diving work and its comprehensive support: staffing, medical, material and technical; 3) the level of protection of divers and personnel involved in carrying out diving work from the effect of harmful and hazardous factors; 4) compliance with the sanitary and hygienic norms and the rules of the work and rest regime established for divers; 5) the use of serviceable diving equipment and process equipment meeting the requirements of industrial safety and safe operation and corresponding to the nature, type and conditions of carrying out diving work.
58. The principal measures to ensure the safety of diving work include: 1) the functioning of the labour protection management system when carrying out diving work in the organisation; 2) the planning of diving work and its proper management when carrying it out; 3) hazard identification, risk assessment, carrying out compensating actions (risk management) and ensuring the protection of divers during diving descents; 4) preparation for actions in the event of abnormal and emergency situations; 5) the selection and preparation of the diving descent site (production territory, work section, area) and of the workplaces of workers involved in carrying out diving work; 6) the organisation of a system of maintenance and repair, rational operation and keeping in serviceable condition of diving equipment, the means of supporting diving descents, tools, appliances and process equipment; 7) the training, advanced training and admission to work of personnel involved in carrying out diving work.
59. The labour protection management system for carrying out diving work shall take into account the specific conditions of the organisation's production activity, the features and specifics of the sphere of economic activity, the features of the operating regimes of facilities, the conditions, nature and types of diving work performed, and compliance with the measures to ensure the safety of diving work.
60. In an organisation carrying out diving work, a risk assessment procedure shall be organised and implemented, which shall include: 1) the identification of hazards; 2) risk assessment as such; 3) documenting the results of the risk assessment; 4) the determination of the conditions under which diving work is suspended or prohibited; 5) the development of compensating actions and measures to eliminate or reduce risks; 6) the development of actions in the event of an emergency situation; 7) informing workers about the risks and the planned measures to reduce risks.
61. When identifying hazards in carrying out diving work, any of the following shall be considered: 1) hazards associated with the conditions of the medium (the effect of elevated pressure of the surrounding environment) in which the diving descents are conducted; 2) hazards associated with the conditions of the external surrounding environment; 3) hazards associated with the work performance technology and the method of conducting divers' descents; 4) hazards associated with the use (failures, malfunctions) of diving gear and equipment, tools, appliances and process equipment, as well as of the means of supporting diving descents; 5) hazards associated with the qualification of personnel and the human factor. A list of typical hazards is set out in Appendix No. 7 to the Rules. When identifying hazards, it is necessary to take into account possible deviations of the production activity at the work facility, changes in the operating regimes of the facility and the available information on abnormal and emergency situations in carrying out diving work.
62. The risk assessment methods are determined by the employer independently, taking into account the nature of its activity and depending on the technological and production operations performed, and are put into effect by the organisation's administrative documents. Different methods of assessing the level of occupational risks may be used for different processes and operations. The selected risk assessment methods shall be provided for by the organisation's labour protection management system.
63. For the purpose of monitoring the serviceable condition of diving gear, diving equipment, process equipment, tools and appliances and the means of supporting diving descents, the correctness of their upkeep, and also of determining the reliability of diving equipment and the degree of wear of individual parts and components, a maintenance and repair system shall operate in organisations carrying out diving work. The maintenance and repair system shall be developed in the form of a programme (a separate standard, manual) or a set of systematised documents characterising the technical condition of the diving equipment. Where the programme is kept on a computer, duplication on paper media shall be ensured.
64. The maintenance and repair system shall include: (a) a maintenance and repair schedule and (or) a schedule of planned preventive inspections and repairs; (b) operating instructions or manuals, data sheets or record cards for all diving gear, diving equipment, process equipment, technical devices and the means of supporting diving descents (hereinafter - diving equipment); (c) records of planned maintenance and repair, stating the periods and frequency of servicing; (d) records of unplanned work, repair work and examinations; (e) records of the availability of spare items and accessories, assemblies and components; (f) identification of the persons carrying out maintenance and repair work, stating who carried out the work, when and to what extent; (g) the methods used for identifying hazards and assessing risks associated with the reliability and failures of technical systems and devices, when extending the service life of the equipment and (or) admitting diving equipment for use where the period of planned maintenance has expired and it is not possible to carry out the work; (h) records of the most critical maintenance and repair actions.
65. Detected malfunctions and damage to diving equipment shall be eliminated immediately by the employer in accordance with the operating instructions received from the manufacturers (suppliers) of the items. Current repairs are carried out by the organisation's workers. Maintenance and repair may be carried out by the organisation's specialists, by specialists of a third-party organisation or of the manufacturer. When checking parts and assemblies of diving equipment that operate under pressure, measures shall be taken to preclude injury to workers. The elimination of malfunctions in systems while they contain compressed air shall be prohibited. Information about the volume and quality of the repair and servicing work shall be recorded under the signature of the persons who carried out that work.
66. For the diving equipment, the employer keeps the relevant operational documentation (a data sheet or record card, operating instructions or manual). The operational documentation is drawn up in the Russian language. Where items of foreign manufacture are used, a translation from the foreign language into Russian is provided in full by the manufacturer or the organisation supplying the item, which is responsible for the completeness and quality of the translation. At the request of the operating organisation, the operational documentation is handed over to the consumer in two languages: in the original and in Russian.
67. For the purpose of safely carrying out diving work when operating diving equipment and keeping it in serviceable condition, the following principal requirements shall be met: (a) the operation, maintenance and repair of diving equipment are carried out by prepared and trained personnel and within the established time limits; (b) no changes are introduced into the diving equipment and equipment that could affect their safe and reliable operation or lead to a reduction of the established operating parameters; (c) during the operation, maintenance and repair of diving equipment there are no violations, breakages, defects or changes affecting the safety of its use or resulting in a reduction of the established parameters; (d) the frequency and extent of maintenance and repair at all stages of the life cycle are established; (e) the procedure for carrying out a working check at the work site before descents or before use for performing the work is established; (f) labour protection instructions for working with diving equipment are developed; (g) records are organised of operating time, malfunctions (breakages, wear, breakdowns, failures) and other parameters affecting the safe operation of diving equipment. Diving equipment and equipment for carrying out diving work shall be stored under the conditions provided for by the operating instructions and shall be subjected to periodic cleaning, drying and disinfection.
68. The working check of diving gear shall be carried out before each use personally by the diver assigned to descend underwater. The working check of diving equipment and of the means of supporting diving descents shall be carried out within the time limits established in the operational documentation for the item, but in any case at least once before the start of diving work (at the beginning of the working day or shift). The instructions on the procedure for carrying out the working check shall be located at the workplaces, freely accessible to every worker. A single set of instructions may be kept at one diving station.
69. Persons who, by virtue of their preparation or experience, or a combination thereof, possess the appropriate practical and theoretical knowledge, abilities and skills are admitted to planned preventive inspections and repairs. Such persons shall be able to determine the degree of wear of individual parts and components, to detect defects, malfunctions or deficiencies and to assess their significance for the safety of the operation of the diving equipment. When operating diving equipment, the requirements of the regulatory legal acts in the field of technical regulation and of other documents governing the requirements for the operation of diving equipment shall be followed, depending on the place of installation or use in carrying out diving work (on shore, at a hazardous production facility, in marine conditions, in the conditions of rivers and inland waterways, at nuclear industry facilities).
70. The measures to eliminate or reduce occupational risks include: 1) the elimination of hazardous work, the suspension of or prohibition on carrying out diving work; 2) the selection of a rational (the safest) method of conducting diving descents and of a way of performing the work; 3) the use of diver protection equipment and the implementation of engineering (technical) methods of limiting the effect of adverse, hazardous and harmful factors on divers and persons involved in carrying out diving work; 4) limiting the time of exposure of workers to adverse, hazardous and harmful factors; 5) the use of PPE and collective protective equipment, as well as of protective devices and appliances; 6) the planning and advance rehearsal of actions in abnormal and emergency situations; 7) the equipping of workplaces ensuring the protection, reduction or elimination of the effect of harmful and hazardous factors on workers who support the descent of divers, against the adverse effect of environmental conditions; 8) the selection of qualified workers.
71. The employer, in accordance with the norms for the issue of PPE, provides the participants in diving work with personal protective equipment, as well as with washing and (or) neutralising agents.
72. The selection of personal and collective protective equipment for workers is made taking into account the safety requirements for the specific conditions of the production activity and on the basis of the results of the assessment of working conditions.
73. To prevent the effect of temperature conditions on a diver working underwater, the selection of the diving gear used shall be approached rationally, the elements of which shall satisfy the requirements as to temperature in the water, at the "water-air" boundary and of the surrounding air. Depending on the temperature of the water and air and the planned time of work underwater, the type of drysuit (wetsuit, diving dress) is selected and, where necessary, additional protective measures are taken.
74. The additional measures to protect a diver from the adverse effect of the temperature of the water and air include: 1) insulating underwear designed for the appropriate temperature range; 2) active means of protecting the diver from overcooling, which include electric heating, water heating, chemical heating, and devices for heating the breathing gas mixtures supplied for the diver to breathe; 3) means of protection against overheating of the diver and of the diving station personnel. Where the air temperature is below minus 15 °C, additional means of shelter and heating shall be used at the diving descent site.
75. When selecting clothing to protect a diver from the effect of the water temperature, the following is used: 1) up to +10 °C - ice-cold water: a working suit and insulating underwear (a thermal-protective coverall, thermal underwear, an insulation liner, woollen underwear, socks (booties), gloves, a fez) or active heating means. Active heating means (water-heated or electrically heated suits) are used at a temperature below +4 °C; 2) from +10 °C to +20 °C - cold water: a working suit or insulating underwear; 3) above +20 °C - warm water: a working suit.
76. The employer provides workers engaged in diving work associated with surface contamination and contamination of the water (the working medium) with diving gear ensuring the complete sealing of the diver, precluding direct contact of the workers with the working medium, and with washing and (or) neutralising agents. The use of drysuits and wet-type items of clothing in diving work associated with surface contamination and contamination of the water (the working medium) when carrying out the work shall be prohibited. At the descent site, the employer shall provide means for washing and cleaning the divers and the diving gear and for washing the hands, and shall provide the supply of working water or air from the main line to the zone of the diver's entry into and exit from the water.
77. When carrying out diving work in conditions of contamination of the breathing air, the personnel shall be provided with respiratory protective equipment and, depending on the situation, with individual dosimetric monitoring devices (individual dosimeters).
78. Depending on the depth of the diving descents and the type of diving gear and diving equipment used, gases and various gas mixtures may be used for divers to breathe: oxygen, air, other breathing gas mixtures (hereinafter - BGM) in various percentage ratios, with parameters suitable for the diver to breathe.
79. A necessary condition for the possible use of gases and breathing gas mixtures suitable for divers to breathe is the availability of decompression tables and instructions for their use, drawn up on the basis of the results of experimental diving descents.
80. The characteristic hazards that may arise when using air and BGM are: 1) the use of gas or BGM not corresponding to the depth of the diver's descent; 2) the use, for breathing or for preparing BGM, of unpurified (contaminated) air with an elevated content of harmful substances; 3) the use, for preparing BGM, of unpurified gases with an elevated content of harmful or inert substances; 4) inadequate quality of regenerative and absorbent substances; 5) elevated humidity of the gas or BGM; 6) the toxic effect of oxygen.
81. The quality of the air shall conform to the requirements applicable to air for divers to breathe. Control analyses of the air supplied for divers to breathe and to the pressure chamber for the content of harmful substances are carried out at least once every 3 months at the regional centre for hygiene and epidemiology of the Federal Service for Supervision of Consumer Rights Protection and Human Wellbeing, at a specialised chemical laboratory or at the diving medical office (laboratory) of a medical and preventive institution or at an organisation entitled to carry out air analysis. Where built-in (permanent) systems for monitoring the quality of the supplied air or breathing gas mixture that ensure monitoring against all the established parameters are present and in operation, the analysis of the air and BGM supplied through these systems is carried out in a laboratory at least once every 12 months, on condition that the readings are registered (documented) during the operation of the monitoring systems. BGM is checked for oxygen content immediately after preparation, 24 hours after preparation (before use) and before each use.
82. The conclusion on the suitability of the air, BGM and chemical air regeneration means (hereinafter - CARM) for the diver to breathe is given by the diving doctor (paramedic).
83. When replenishing air supplies, the wind direction, the location of the air intake point and other factors that may affect the reduction of air quality and lead to contamination of the air supplied for the diver to breathe shall be taken into account. Where contamination of the air or breathing gas mixture is detected and (or) complaints are received from divers about the quality of the inhaled air, the diving descents and work shall be suspended.
84. Where harmful substances in concentrations above the established maximum permissible concentrations (hereinafter - MPC) are detected in the air supplied for the diver to breathe and to the pressure chamber, the air is released from the cylinders and the cylinders are recharged with air. In the event that the MPC of harmful substances is exceeded on repeat analysis (an exceedance of the MPC of at least one substance), the descents shall be prohibited and measures are taken to identify and eliminate the cause of the air contamination. After the causes have been ascertained and eliminated, servicing to the extent of the annual check shall be carried out in accordance with the operating instructions for the diving gear used and the cable-hose bundles (hereinafter - CHB).
85. Disinfection of diving gear is carried out in the following cases: (a) upon its receipt from the store or from other organisations before use; (b) before each descent where the same gear is used by different persons; (c) periodically after an established number of descents during operation, or weekly where diving descents are conducted intensively and diving gear and equipment are used; (d) after descents into contaminated and (or) domestic waste waters; (e) upon the appearance of infectious or skin diseases in divers who have used the gear.
86. The types of labour protection briefings are established by the procedure for training in labour protection and for checking knowledge of the labour protection requirements of workers of organisations, approved by the Ministry of Labour and Social Protection of the Russian Federation in accordance with sub-clause 5.2.28 of the Regulation on the Ministry of Labour and Social Protection of the Russian Federation, approved by Government Resolution No. 610 of 19 June 2012 (Collected Legislation of the Russian Federation, 2012, No. 26, Article 3528).
87. Daily, before carrying out diving work, labour protection briefings shall be conducted at the workplace. The person in charge of the diving work briefs on the general matters of the organisation of carrying out diving work, which include: (a) the arrangement of the work facility (structure, vessel), the operating regimes and the current situation at the work facility (section); (b) the procedure for and time limits of performing the technological stages (operations), compliance with the work technology provided for by the process chart for carrying out diving work (the programme, project) for the forthcoming shift; (c) the situation of the surrounding environment and the conditions in the area of carrying out the work (at the work sections); (d) the features of the forthcoming work, if any; (e) the safety measures on the surface provided for by the permit to work and the internal order rules at the work facility; (f) the organisation of interaction between all participants in the work and the distribution of personnel; (g) the use of personal and collective protective equipment; (h) actions in emergency situations. The results of the briefing are recorded in the labour protection briefing log at the workplace.
88. The person in charge of the diving descents conducts a briefing for the personnel directly involved in carrying out the diving descents, which includes the following matters: (a) the distribution and clarification of the duties of all the diving station personnel for the period of the descents; (b) the procedure for changing (relieving) the support personnel; (c) the features of the underwater part of the facility (at the work section) and the conditions for ceasing the descents; (d) the selected diving descent methods and the features of their support; (e) the procedure for carrying out the preparation for the descents, the descent, the stay underwater, the diver's ascent and the post-descent servicing; (f) the ways or technologies of performing the work underwater; (g) the use of protective devices and appliances. The person in charge of the diving descents gives the task to each working diver and establishes the safety measures for each immersion. The results of the briefing are recorded in the diving work log.
89. The general management of the diving work is exercised by the person in charge of the diving work, who is appointed by the employer and is a representative of the organisation carrying out the diving work.
90. The appointment of the person in charge of the diving work shall be made taking into account the specific conditions of the production activity, depending on the nature of the forthcoming work and the competence of the organisation's official: education, training or qualification, work experience and official duties in the organisation and on the project (on the work).
91. The person in charge of the diving work may not be appointed in the following cases: (a) when conducting educational, training and qualification descents in swimming pools and in open water bodies under normal conditions (immersion conditions meeting all of the following requirements: open access to the surface throughout the immersion, the absence of movement of vessels and motorised craft on the water surface in the zone above the underwater route, visibility not below 5 m, surface waves not exceeding 0.5 points on the Beaufort scale, current speed not exceeding 0.1 m/s, water temperature not below 15 °C, air temperature not below 0 °C, the presence of a solid bottom at depths of up to 30 m within the underwater route, the locality being situated below 300 m above sea level, daylight hours); (b) when conducting therapeutic recompression and training descents by the method of short-term immersions (hereinafter - STI) in a pressure chamber; (c) when conducting diving descents under conditions where the safety of carrying out the diving work depends exclusively on the actions of the person in charge of the diving descents, the functions of the person in charge of the diving work may be performed by the person in charge of the diving descent. The duties of the person in charge of the diving work and the person in charge of the diving descents may be combined only on condition that there are no grounds for the possible distraction of the attention of the person in charge of the diving descents from the diver's descent itself. The possibility of combining duties shall not lead to a reduction of the level of safety of the diving work. During descents from small craft, the duties of the person in charge of the diving descents and of the senior person on the craft may be combined. When performing work involving the descent, ascent or movement of divers in diving stages, it is possible to combine the duties of the person in charge of the diving descents or of the diving work with the duties of the person responsible for the safe carrying out of work using lifting equipment (where the appropriate training and admission are held).
92. When carrying out diving work on a round-the-clock basis (three or more work shifts), during the simultaneous operation of two or more diving stations, during the simultaneous work of more than two persons in charge of diving descents, when carrying out diving work requiring the person in charge of the diving work to have special preparation and knowledge of the technology of conducting and (or) carrying out diving work, or when carrying out diving work at depths of more than 60 m, a responsible performing authority for the diving work is appointed from among the diving specialists to manage the diving work. The responsible performing authority for the diving work shall be admitted to the management of diving work and the management of diving descents, shall hold a diving qualification and shall possess experience of carrying out diving work.
93. The person in charge of the diving work shall undergo training under vocational training or supplementary vocational education programmes on the management of diving work and a knowledge assessment on labour protection when carrying out diving work in the organisation, and shall hold an admission to the management of diving work valid for the current year.
94. The person in charge of the diving work is responsible for the organisation of the safe performance of diving work at the facility, the performance of the safety actions specified in the permit to work and their sufficiency, the additional safety measures taken that are necessary under the conditions of performing the work, the completeness and quality of the labour protection briefings, the constant observation of the conditions and situation in the area of carrying out the work, and the organisation of interaction with the owner of the facility and other persons whose actions may affect the safety of the diving work. The specific duties of the person in charge of the diving work shall be established by the organisation's administrative acts.
95. Before the start of diving work, the person in charge of the diving work shall take into account the following principal factors: (a) the reliability of the holding or the safety of the mooring of the vessel (safety at the diving work section); (b) the safety of the navigational or road situation; (c) the deployment of forces and resources at the work section; (d) the competence and condition of the persons involved in the diving work and descents; (e) the conformity of the environmental conditions to the safe conditions for descents; (f) the capabilities for monitoring changes in the hydrological and meteorological situation in the area of carrying out the diving work; (g) notification of the location (section) of carrying out the diving work to the owner of the facility and the duty, dispatching, operational and servicing personnel at the work facility; (h) the internal order rules of the organisation and the features of the operating regime at the work facility (section) and the capabilities for changing it; (i) the availability of information about the hazards underwater and on the surface at the facility in the area of carrying out the diving work; (j) the rational selection of the diving descent sites and of the sections for conducting the descents; (k) the availability of permanent two-way communication with the responsible representative of the owner of the facility and other participants in the work; (l) the condition and level of the general organisation and safety on the vessel, facility or hydraulic engineering structure and the stability of its individual elements; (m) compliance with the requirements for the equipping of the diving station workplace, the provision of personal protective equipment and the need for measures to restrict movement at the work site; (n) the absence or emergence of hazards not taken into account in the risk assessment.
96. The person in charge of the diving work shall notify the port supervision authorities (the enterprise administration, the facility owner, the duty dispatcher, the operational personnel) of the commencement of the diving work.
97. Where necessary, the person in charge of the diving work notifies of the commencement of the diving work those organisations located in the area where the work is carried out (floating structures moored in the immediate vicinity) whose production activities may affect the safety of the divers and of the diving station personnel and whose property may potentially be damaged.
98. The person in charge of the diving work shall agree and clarify with the facility owner the procedure of actions in the event of possible abnormal and emergency situations.
99. The responsible performing authority is responsible for coordinating the work of the shifts and diving stations at the work site (project), for continuous monitoring of the diving work, for the fulfilment of safety measures and for compliance with the technology for conducting and carrying out the diving work. The responsible performing authority (hereinafter the RPA) shall be constantly present at the site where the diving work is carried out and may be a representative of the organisation performing the diving work. Where several diving stations operate simultaneously at different locations, the RPA shall take up a position convenient for direction that enables the control and monitoring of all operating diving stations. The responsible performing authority shall not be entitled to leave the work site until the work is suspended or terminated.
100. The responsible performing authority for diving work is appointed from among diving specialists and shall be competent (trained) in the management of diving work and of underwater and other types of work necessary for directing the diving work under the specific conditions of the organisation's production activities.
101. The person in charge of the diving descent exercises direct direction of the diving descent and monitoring of the actions of the divers and of the personnel involved in supporting the diving descent, and is responsible for: (a) organising the conduct of the diving descent, all aspects of safety and ensuring them at the assigned work section, and the direct admission of the personnel to work before the descents; (b) selecting a safe method of descents and a means of performing the work (assignment), rational means of supporting and providing standby cover for the diver, monitoring compliance with safe working techniques underwater and, by the support personnel, at the workplaces; (c) assessing the risks before the diving descents and at all their stages, and taking the decision to conduct, complete or continue them; (d) readiness to act in the event of an emergency situation during the diving descent at all its stages.
102. The person in charge of the diving descent shall: 1) during the pre-descent period and when preparing the diving descent: (a) determine the procedure for performing the tasks set; (b) ensure that the environmental conditions and the hydrological and hydrometeorological regimes at the descent site permit the diving descents to be carried out safely, and enter them in the diving work log; (c) ensure that the diving station personnel hold admissions to work; (d) ensure that the state of health of all the diving station personnel permits them to perform the tasks set for them without distraction; (e) check the general readiness of the diving station's workplaces, the divers' descent point and the section of the forthcoming work; (f) check the reserves and quality of the air (breathing gas mixtures) and of the regenerative and absorbent substances; (g) ensure that the prescribed checks of the diving gear and equipment, tools, appliances and process equipment, and of the means of supporting the diving descents, have been carried out and that records of the check results have been made, and personally ascertain the readiness of the gear and of the descending and standby divers; (h) distribute the duties among the diving station personnel and assign them to their workplaces, and direct the dressing of the divers; (i) ensure that everyone whose activities affect the safety of the work is aware of the commencement of the diving descents and of the place where they are carried out; (j) conduct a workplace briefing of the personnel and ensure that the diving station personnel have understood their duties, are aware of their responsibility, of the conditions for conducting the descents, of the safe methods and techniques for performing the work, understand the risks of the forthcoming work, know the safety measures and are able to act in the event of an abnormal or emergency situation; (k) verify the currency of the identified possible hazards and risks and the adequacy of the compensating actions; (l) perform the necessary calculations and establish the procedure for monitoring the adjustable and variable parameters during the diving descents; (m) ascertain the readiness of the decompression chamber and, in its absence, clarify the arrangements and the procedure of actions in the event of an abnormal or emergency situation and the location of an operational decompression chamber; (n) ensure that the appropriate warning signals indicating that diving work is in progress have been hoisted; (o) if the situation, the descent conditions or the nature of the work change from those planned, carry out a risk assessment and determine additional safety measures or suspend the descents; (p) set the tasks for the working (descending) divers before each descent, explain the safe method of descent and ascent and the techniques (means) for performing the work (task), the risks and the safety measures during the diving descents and work; (q) establish the readiness and location of the supporting watercraft in the cases provided for by the Rules; (r) select the preliminary decompression schedule, determine the permissible time for the diver to remain underwater in accordance with the working decompression tables, establish the working time at depth or the bottom exposure time, and the time and procedure for ascent (surfacing, exit) to the surface; (s) establish the degree of readiness of the standby diver and determine the manner and place of support for providing standby cover for the diver; 2) during the diver's submersion: (a) ensure the tightness of the diving gear and give the command to descend; (b) monitor the rate of descent; (c) monitor the correct performance by the attendant divers of their duties; (d) direct the movement of the diver when a diving stage or bell is used; (e) give commands to the divers who are underwater; (f) keep a record of the time worked underwater, from the moment the descent begins; 3) during the diver's presence at the work location (the bottom, the facility): (a) monitor the time the diver remains underwater and the diver's state of health; (b) monitor the position of the divers underwater and at the work location; (c) monitor the quantity of air (BGM) supplied for the diver's breathing and/or the operating time of the diving breathing apparatus; (d) direct the actions of the working diver underwater and of the persons supporting the diving descents; (e) monitor the readiness of the standby diver; (f) monitor the duration of the submersion, keep track of the established working time, the actual depth and the submersion profile throughout the descent; (g) exercise control over the surrounding situation and its changes; (h) maintain communication with the person in charge of the diving work and with other persons designated by the descent planning documents; (i) maintain communication with the divers who are underwater; 4) during the diver's ascent: (a) monitor compliance with the decompression schedule during the diver's ascent; (b) not later than 3 to 5 minutes before the end of the working time at depth, inform the diver of the need to finish the work and begin the ascent; (c) after the working diver has finished the work (completed the assignment), grant the diver permission to exit and direct the diver's ascent until the descent is complete and the diver is undressed on the surface; (d) report to the person in charge of the diving work on the ascent (exit) of the working diver to the surface and on the completion of the work; (e) direct the actions of the support personnel during the diver's ascent; (f) in the event of an abnormal or emergency situation involving the diver, act in accordance with the action plan developed and having regard to the situation, taking all possible measures to assist the diver in distress; 5) during the post-descent period: (a) ask the diver about the diver's state of health and ensure the absence of signs and symptoms of the onset of diving illnesses; (b) direct the undressing and, where necessary, the transfer of the diver to the decompression chamber; (c) direct the bringing of the diving gear and equipment into readiness for subsequent use; (d) make the necessary entries in the diving work log; (e) organise the cleaning of the workplaces, identify and bring the diving equipment to the appropriate readiness, and place it in the designated storage locations; (f) inform the person in charge of the diving work of any deficiencies and observations in the operation of the diving station and of the necessary and adopted measures to eliminate them; (g) take part in preparing the documentation for the work performed and in drawing up diagrams, sketches and other materials on the results of the work performed. Where there are particular features in the organisation of the conduct of the diving work under the specific conditions of production or service activities, the duties of the person in charge of the diving descents shall be clarified and determined before the commencement of the diving work.
103. If any doubts arise as to the correctness of actions, processes or operations during the diving descents, the person in charge of the diving descent shall take decisions on the side of safety and take measures to protect the diver and/or terminate the diving descent with the subsequent ascent of the diver to the surface.
104. Workers who have a diving qualification, special training in supervising diving descents and diving work experience established in the unified tariff and qualification reference books or in the professional standards, having regard to the type of professional activity and the specific conditions of the production activity, may be admitted, by order of the employer, to supervise diving descents and training descents in the decompression chamber at depths of up to 1.0 MPa. Workers who have special training in supervising diving descents but who do not hold clearance for descents on health grounds may be admitted to supervise diving descents where they have diving work experience of not less than 10 years from the start of their diving practice and experience of supervising diving descents of not less than 3 years.
105. Specialists who have experience of working as a person in charge of diving descents at depths of from 20 to 60 m for not less than 3 years, and diving specialists who have a length of service in the post or experience of working as a diving specialist of not less than 1 year and who have undergone special training in supervising diving descents beyond 60 m, may be admitted to supervise diving descents at depths exceeding 60 m.
106. Where diving descents are carried out using diving systems with an open diving bell, the requirements for the admission of the person in charge of the diving descents are established by the administrative acts of the organisation operating this equipment, having regard to the recommendations of the equipment manufacturer and to the experience of carrying out similar work.
107. During the preparation and conduct of the diving descent and during the post-descent period, the divers and the assigned support personnel are subordinate to the person in charge of the diving descent, irrespective of the post they hold in the organisation. The person in charge of the diving descents shall be entitled to give instructions and set tasks to all the diving station personnel and to the auxiliary personnel attached to the diving station concerning all aspects of the safety of the conduct of the diving descent. Before the diving descents begin, the person in charge of the diving descents shall obtain the permit to work and the other planning and process documents. After studying them, the person in charge shall distribute the duties among the divers, establish the order of the divers' descents, assign a task to all the diving station personnel, explain the technology and the procedure for performing it, the chosen method of the diving descent and the means of performing the work (task), and also communicate to the personnel their duties in the event of an abnormal or emergency situation.
108. The person in charge of the diving descent shall establish the readiness of the standby diver for the descent. The readiness is established depending on the conditions for conducting the diving descent, the chosen method of the diving descents, the diving gear and equipment used, the manner of the work (task performance) and the chosen method of providing standby cover. Two degrees of readiness of the standby diver are distinguished: (a) readiness No. 1 (immediate) - the standby diver is fully dressed in the diving gear and breathes from the atmosphere; (b) readiness No. 2 - the standby diver is dressed in waterproof protective clothing (a diving dress, a dry suit or a wet suit), the remaining items of the diving gear being ready for immediate donning; (c) readiness No. 3 - the standby diver is dressed in thermal underwear (in working uniform or in underwear in hot weather, during descents to shallow depths in clean water), the remaining parts of the diving gear being ready for immediate donning. The immediate readiness of the standby diver is declared during training diving descents, descents from small craft, descents under ice, descents in a current, into flooded premises and facilities with a confined or enclosed space, descents in mountain conditions and in other conditions, having regard to the situation. During diving descents in a pair and descents using a diving stage or bell, the position of the standby diver may be determined underwater. In that case, an additional standby diver shall be appointed at the surface. The length of the standby diver's cable-hose bundle shall be greater than the length of the working diver's cable-hose bundle.
109. No one shall be entitled to interfere in the direction of the diving descents or to give any instructions to the divers and the support personnel. Only the person in charge of the diving work may give instructions to the person in charge of the diving descent during the descents.
110. In the event of incorrect actions by the person in charge of the diving descent that may lead to an emergency or an accident, the person in charge of the diving work shall suspend (terminate) the descents and may thereafter remove the person in charge of the descent from the performance of the duties. Thereafter, the person in charge of the work shall personally direct the descent and, if he does not hold clearance to supervise descents, he shall appoint another person in charge of the descent who holds such clearance. The reverse handover of the direction of the descent is not carried out before the descent is complete (the underwater work is stopped, the working diver is raised to the surface, and only after that is the reverse handover of the direction of the descent carried out). The assumption of the direction of the diving descent and the reverse handover of the direction of the descent shall be announced verbally to the diving station personnel, and an entry shall also be made in the diving work log.
111. The replacement of the person in charge of the diving descent during the conduct of the diving work is permitted if it is caused by production necessity and is entered in the planning documents. An additional briefing of the divers and the attendants need not be carried out in that case, except for the notification of the replacement of the person in charge of the diving descent, which shall be communicated to every participant in the descents (work). The entry on the handover and acceptance of the duties in the diving work log is signed by the person handing over the duties and by the person accepting them, with the time of the replacement indicated.
112. For the direct direction of the day-to-day activities of the diving station, an official from among the most experienced divers (the foreman of the diving station, the team leader, the senior diver, the head of the diving complex) shall be appointed, on a permanent or temporary basis, by order (instruction) of the head of the organisation.
113. The official appointed for the direct direction of the activities of the divers (the diving station) is responsible for the readiness of the diving station for work, the maintenance in good working order and the correct operation of the diving equipment, the upkeep of the premises and of the permanent workplaces of the diving station, and the maintenance of the accounting and reporting documentation.
114. The official exercising the direct direction of the day-to-day activities of the diving station during the servicing or repair of the diving equipment is responsible: 1) where the servicing is carried out by the organisation's workers: (a) for preparing the premises and the diving equipment for servicing and repair to a condition that ensures the safety of the conduct of the work; (b) for preparing the workers to perform the work by safe methods and means, and for compliance with the labour protection rules during the conduct of the work; (c) for quality control of the servicing and repair work performed on the diving equipment; 2) where the work is performed by a third-party organisation: (a) for the timely and complete provision of the diving equipment and its documentation; (b) for ensuring quality control of the servicing and repair work performed on the diving equipment.
115. The divers and the diving station personnel shall carry out the instructions and tasks set by their immediate supervisor and bear personal responsibility for carrying them out. After the person in charge of the diving descents has been appointed, the divers and all the diving station personnel come under his subordination from the moment the briefing and the distribution of duties for the descent are conducted. On receiving instructions or being set tasks that may affect the safety of the diving descents or threaten the personal safety of the diver, any worker shall be entitled to report the hazards he has identified and, where necessary, to apply to a higher-ranking supervisor or to the head of the organisation. Matters that may affect the safety of the diving descents shall be resolved before the diving work or the diving descent begins.
116. At the diving station, before each diving descent, the distribution of duties among the divers shall be carried out in the following order: (a) the diver assigned to descend underwater - the working (descending) diver; (b) the diver assigned to the cable-hose bundle (cable-signal) - the attendant diver; (c) the diver assigned to assist the working diver - the standby diver; (d) the diver assigned to attend the standby diver - the attendant for the standby diver. The distribution of duties among the divers is carried out by the person in charge of the diving descent. The person in charge of the diving descent may not perform the duties of the standby diver. A diver shall be entitled to perform underwater only that work (task) which has been set by the person in charge of the diving descent and which he is ready or trained to perform.
117. The duties of the participants in the diving descents are developed within the organisation in the form of labour protection instructions and/or job descriptions. The category of the instructions and the scope and nature of the rights and duties set out in them are determined depending on the conditions for conducting the descents, the nature and type of the diving work and the place where it is carried out, the method of the diving descents and the means of performing the work (task), the number of personnel at the diving station, the diving equipment, diving systems, means of supporting the diving descents and process equipment used, having regard to the requirements of the regulatory legal acts on labour protection and industrial safety and to the administrative documents of the organisation. The duties of the divers and of the persons engaged in supporting the diving descents shall include the following stages of the preparation and conduct of the diving descents: (a) the pre-descent stage; (b) during the submersion; (c) during the diver's presence at the work location (the bottom, the facility); (d) during the diver's ascent; (e) the post-descent stage; (f) the inter-descent stage. When diving descents are carried out, depending on the descent conditions, the type and nature of the work, the manner of its conduct, the method of the descents and the diver's working time, the stages of the preparation and conduct of the diving descents may differ from those indicated above. In that case, the stages of the preliminary and final preparation for the diving descents, the decompression stage and the post-decompression stage (period) are distinguished.
118. Where necessary, in addition to persons of a diving occupation, other workers may be engaged as support personnel from among persons admitted by order of the head of the organisation (the ship's master) and who have undergone a targeted workplace briefing with a corresponding entry in the log. For engaging additional auxiliary personnel in the event of an abnormal or emergency situation, the conduct of briefings is not required, or an oral briefing may be conducted without making an entry in the briefing log.
119. On detecting a fault in the diving equipment, the equipment, the means of supporting the diving descents, tools, appliances, personal and collective protective equipment, on the occurrence of abnormal or emergency situations or of the preconditions for their occurrence, the person in charge of the diving descents and the person in charge of the diving work shall be notified immediately. The work being carried out at that time shall be stopped or suspended until the faults are eliminated. Working with faulty diving equipment, tools, appliances and process equipment or with the means of supporting the diving descents, and using faulty personal and collective protective equipment, shall be prohibited.
120. In the event of feeling unwell, of an unfavourable change in the situation, of the detection of a malfunction of the diving gear or of mechanical damage to its individual parts, the working diver shall stop work, inform the person in charge of the diving descent and act in accordance with his instructions and, where necessary, take urgent measures with a subsequent report, and surface, having regard to the situation. If the communication means fail, the working diver shall act independently to prevent and eliminate the emergency situation; for communication with the surface, he shall switch to the use of prearranged signals using the cable-hose bundle or the signal line. Where it is impossible to use the communication means, including the transmission of prearranged signals, the working diver surfaces or returns to the diving stage or bell, having regard to the situation.
121. The standby diver is appointed to provide direct assistance to the working (descending) diver in distress from among the most experienced divers who possess the skills to perform actions to assist a diver in distress. The appointment of the standby diver is carried out by the person in charge of the diving descent when duties are distributed among the station's divers before the diving descents begin, and remains in force until those descents are complete. The appointment of a standby diver from among trainee divers shall be prohibited.
122. When two working divers descend underwater simultaneously (a paired descent) from a single diving station under the direction of a single person in charge of the diving descent, one standby diver is appointed. During the diving descent, the standby diver is subordinate to the person in charge of the diving descent. The replacement of the standby diver is carried out with the permission or on the instruction of the person in charge of the diving descents. When a descent time of over two hours is planned, provision shall be made for the replacement of the standby diver. The standby diver is responsible for the prompt and effective provision of assistance to the diver in distress in the water and underwater. The standby diver, while underwater, shall be entitled to take the decision on the manner of assisting the diver in distress, proceeding from the actual situation and having regard to the safety requirements. During the preparation of the diving descent, the standby diver shall: (a) receive from the person in charge of the diving descent the task and a briefing on the procedure for its performance; (b) prepare and carry out an operational check of the standby diving gear. The standby diver's signal line (hose-cable, CHB) is calculated in such a way that it is not shorter than the working diver's signal line. Before the descent, the signal line is untangled (in cold weather, dried) and checked for the absence of damage and knots. The signal line is laid out in one of the ways that ensure unhindered paying out, and the standing end of the signal line is secured at the descent point. The diving knife shall have a sharp edge, secure retention in its sheath and the possibility of rapid withdrawal with either hand. The following shall be prohibited: (a) the standby diver working on a control line; (b) the use of signal lines after untying heavily tightened knots; (c) securing the signal line to the standby diver with a slip loop, and also fastening it to the fittings of the breathing apparatus or to other items of gear not intended for this; (d) the use by the standby diver of knives with a double-edged blade, of beak-shaped rope cutters and of scissors; (e) the use of closed-circuit breathing apparatus for the standby diver. If faults in the standby diving gear are detected during the operational check, the faults are eliminated before the diving descents begin. The results of the operational check are reported to the person in charge of the diving descent and confirmed by a signature in the diving work log (hereinafter the DWL). The standby diver receives from the person in charge of the diving descent the task, the briefing and instructions on his location and degree of readiness. The standby diver dons the items of the diving gear on the instruction of the person in charge of the descent and reports to him his readiness; the items of gear not donned are kept at the place indicated by the person in charge of the descent, separately from the gear of the other divers, in readiness for immediate donning. The tightness and buoyancy of the standby diver are checked and brought to the norm before the diving descents begin. The diver (worker) assigned to attend the standby diver is kept beside him in readiness to perform his duties. The person in charge of the descent determines the nature of the duties performed by the standby diver during the submersion and underwater work of the working diver. If the descent conditions and the established degree of readiness do not permit the standby diver to perform work to attend the working diver, he shall remain in the established readiness for descent, without performing work, while observing the situation. The standby diver shall be prohibited from: (a) descending underwater without the instruction of the person in charge of the descent; (b) leaving the descent point before the working diver is fully undressed or before his own replacement; (c) using diving gear not checked by him personally; (d) distracting the persons attending the diving descents with extraneous conversations; (e) removing the diving gear without the permission of the person in charge of the descent; (f) sleeping and using headphones, a telephone or other electronic devices. The standby diver shall inform the person in charge of the descent in good time of the need for his replacement if, for any reason, he is unable to continue performing his duties. The presence of the standby diver in the water not connected with the provision of assistance to a diver in distress shall be prohibited, the exception being a brief descent to check the tightness of the diving gear and the buoyancy of the diver. On receiving an emergency signal from the diver, the standby diver shall, on the instruction of the person in charge of the descent, descend into the water to assist the diver in distress. The descent of the standby diver is carried out along the cable-hose bundle (signal line) of the diver in distress. During the descent and while underwater, the standby diver performs the duties established for the working diver and acts in accordance with the instructions of the person in charge of the diving descent. The main tasks of the standby diver are: (a) searching for and finding the diver in distress; (b) visually determining his condition (conscious, unconscious); (c) switching the diver in distress to breathing from an apparatus with a reserve supply of air; (d) releasing the diver in distress; (e) raising the diver in distress to the surface and towing him to the shore or a watercraft; (f) ensuring that the diver in distress undergoes decompression in the water. If the diver in distress is unconscious, his ascent is carried out in the shortest possible time without observing the decompression schedule. In doing so, the standby diver supports the head of the diver in distress, preventing it from dropping face down. If the diver in distress is conscious, his ascent is carried out either immediately or according to the appropriate schedule. The decision to carry out decompression in the water is taken by the person in charge of the diving descent. The diver in distress may be raised only after his signal line or CHB has been freed from any snagging (jamming) and the standby diver has given the signal to surface. After the diver in distress has been raised out of the water, the standby diver, on command, exits the water (onto the shore or a watercraft) and acts on the instructions of the person in charge of the diving descent. During the ascent and exit to the surface of the working diver, the standby diver (if he has not descended underwater) shall: (a) with the permission of the person in charge of the diving descent, remove from himself the diving gear or parts of it; (b) after the completion of the diving work, take part in bringing the diving equipment to the established readiness and in cleaning the workplaces.
123. Divers and other workers who service diving descents and work perform the following functions: (a) preparing tools, fixtures, diving hardware and the means of supporting diving descents for the descents, and preparing the workplace of the diving station; (b) dressing and undressing the diver; (c) checking and installing the means for the diver's descent, holding the cable-hose bundle of the working diver, operating the launch and recovery devices, holding the guy lines, under-keel lines and other working lines, and passing tools; (d) communication with the working diver; (e) operating the pressure chamber; (f) supplying air (breathing gas mixture) to the diver and filling the cylinders with it; (g) supplying and switching on (switching off) the working tools, equipment and working media to the equipment; (h) supporting diving descents on the duty watercraft. The person in charge of diving descents establishes and distributes duties at all stages of diving descents and work at the diving station.
124. An attending diver may be a worker of a diving or non-diving occupation who provides direct support (servicing) to the working diver at the pre-descent and post-descent stages of a diving descent, and who, while the working diver is in the water and underwater, maintains a mechanical connection with him. The attending diver is responsible: (a) for his compliance with the labour protection rules when supporting diving descents; (b) for the quality performance of the preparation and checking of the means of supporting diving descents and work assigned to him; (c) for holding the descending diver from falling into the water from the moment the signal line is attached to him until the moment the diver submerges underwater; (d) for the correct donning by the diver of the parts of the diving gear; (e) for preventing the diver from falling to depth during his descent and ascent along the descent line; (f) for the correctness and timeliness of the transmission of pre-arranged signals to and from the diver; (g) for bringing the support means assigned to him to the established degree of readiness upon completion of the diving descents.
125. While the working diver is working underwater, the attending diver shall be prohibited from: (a) being distracted from his duties, conducting extraneous conversations and distracting others; (b) releasing from his hands the cable-hose bundle (signal line, signal cable, diving hose); (c) simultaneously supporting the work of two or more divers working on different signal lines; (d) smoking and using mobile communication; (e) transferring the cable-hose bundle (signal line) to other persons without the permission of the person in charge of the diving descent. When providing telephone, hydroacoustic or other types of communication, commands from the person in charge of diving descents to the diver and from the diver to the person in charge of diving descents shall be promptly transmitted, and the attending diver shall thereby make sure that these commands have been received and correctly understood. During descents of divers in self-contained diving gear using the signal line for communication, the diver's well-being shall be enquired about periodically (no less frequently than every five minutes) throughout the entire time of the diving descent. Where workers of a non-diving occupation are involved in support, the attending diver, from among the divers, shall monitor the correctness of the actions they perform. The attending diver, upon detecting an unassisted ascent of the diver, shall note the time of the ascent and immediately report to the person in charge of the diving descent and act in accordance with his instructions.
126. While the diver is underwater, the diver attending on the cable-hose bundle shall not release it from his hands. The attending diver may transfer the cable-hose bundle (diving hose, signal cable, signal line) to another diver only with the permission of the person in charge of the diving descent. During a changeover, the attending diver takes up the slack of the cable-hose bundle, enquires by communication or by a pre-arranged signal about the well-being of the working diver in the presence of the attending diver appointed for the changeover, and transfers to him the cable-hose bundle or the signal line. In doing so, the diver's well-being, the depth of the descent, the length of the paid-out cable-hose bundle, the nature of the work being performed and the presumed location of the diver are reported to the person in charge of the diving descent. The relieving attending diver, having received a reply via the cable-hose bundle or the signal line, shall report to the person in charge of descents on the changeover carried out, and, when working without telephone communication, shall personally make sure of the well-being of the working diver by means of a repeated enquiry by a pre-arranged signal.
127. When conducting diving descents using a diving bell (hereinafter - the DB), a diving bell diver-operator is appointed from among the divers who have undergone additional training. The DB diver-operator is responsible for the quality of the preparation and operational check of the DB systems and devices, the correct operation of the DB systems and devices during the descent, the maintenance of the prescribed composition of the gas environment in the DB and the support of the divers working outside the bell (from the bell). The duties of the DB diver-operator are established depending on the type of diving complex by the local acts of the organisation.
128. The employer shall provide a sufficient number of workers (personnel); the qualification of the workers shall correspond to the nature of the forthcoming diving work. The required number of divers and persons supporting diving descents shall be established depending on: (a) the conditions for conducting diving descents; (b) the nature and type of diving work in the specific - conditions of the production activity; (c) the number of divers admitted to underwater descents and the need for simultaneous work of divers underwater; (d) the number of working hours per day (shift) and the total duration (term) of the performance of the work; (e) the diving hardware, diving complexes and equipment used and the place of their location (on the shore, on a vessel); (f) the place of performance of the diving work (on inland waterways and water areas, in coastal waters, on the open sea, in pools or aquariums); (g) the chosen methods of performing descents and the ways of performing diving work; (h) the requirements for the decompression of divers and the capabilities for carrying it out, including in the event of an emergency situation with a diver; (i) the hazards identified and the results of the risk assessment before the diving work; (j) the requirements of the Rules, as well as other standards and administrative acts on the conduct of diving work adopted in the organisation.
129. The diving station shall be staffed with divers in accordance with the norms specified in Appendix No. 1 to the Rules and with the additional number of divers, for various types of diving work, specified in Appendix No. 2 to the Rules.
130. The minimum required list of equipment for the safe conduct of diving work shall include diving equipment and means of supporting diving descents at the diving station: (a) the main source of supply of breathing air; (b) the reserve source of supply of breathing air; (c) the breathing air supply panel when using the gear in the hose configuration with a cable-hose bundle; (d) means of communication with the diver; (e) a means of measuring depth during underwater work and a means of recording the working time to an accuracy of one minute; (f) a means of lowering and raising divers (for the working and standby diver). For the divers - no fewer than two sets of diving gear for the descent, of the working and standby divers: (a) a diving drysuit, wetsuit or diving shirt with a set of body and (or) insulating underwear, gloves (mittens) and booties (socks); (b) a helmet, a full-face or band mask or a half-mask complete with a reducer and a demand valve (first- and second-stage regulators); (c) a cylinder with the main and reserve supply of breathing air when using the gear in the self-contained configuration; (d) a weight belt or the diver's weight system (weights); (e) galoshes and (or) fins; (f) a diving knife; (g) a signal line; (h) a safety harness (suspension system) that ensures the raising of a distressed diver in the vertical position.
131. The organisation shall define (establish) a list of the necessary equipment and gear for the safe performance of diving work, based on the specific conditions of the organisation's production activity for stationary and non-stationary workplaces. Before the start of the performance of diving work, the person in charge of diving descents independently clarifies the composition of the diving gear and equipment used.
132. The list of equipment for the safe performance of diving work, taking into account the type and nature of the diving work as well as the place of its conduct, is established by the standards and administrative acts of the organisation.
133. Diving descents may be conducted in normal, complicated, difficult and special conditions. The following are considered normal conditions for the performance of diving descents and work: (a) a descent depth of up to 12 m; (b) the speed of the underwater current - less than 0.5 m/s; (c) sea state of the water surface below 2 points (wave height less than 0.75 m); (d) water temperature of no less than 10 °C and no higher than 30 °C; (e) ambient air temperature above 0 °C; (f) an underwater visibility radius of no less than 1.0 m; (g) atmospheric pressure greater than 700 mmHg; (h) a wind force of up to 12 m/s; (i) the absence of obstacles to the movement of the diver in the water and on the bottom; (j) work during daylight hours; (k) the absence of contamination of the water with harmful impurities (not contaminated with toxic and radioactive substances, containing no petroleum products or domestic waste).
134. Difficult conditions for the performance of work include work in conditions differing from normal ones, when three or more factors are below or above their normal indicators: (a) a descent depth of more than 12 m, (b) atmospheric pressure of up to 700 mmHg, (c) water temperature below 10 °C and above 30 °C; (d) an underwater visibility radius of less than 1.0 m; (e) visibility on the water surface of no more than 100 m; (f) an underwater current speed from 0.5 m/s to 1.0 m/s; (g) sea state of the water surface of 2 points or more; (h) work is performed on cluttered bottom, in narrow, cramped places and in a restricted-confined space; (i) the movement of the diver underwater is hindered owing to the presence of obstacles of a natural or man-made nature; (j) work during the hours of darkness; (k) descents under ice; (l) descents are conducted where the height of the descent point above the level of the water surface is more than 2 m. Where no more than three factors differ from normal ones, the work is complicated.
135. Special conditions for the performance of work include: descents in extreme weather conditions (at an ambient air temperature below minus 30 °C, and, where there is wind at a speed of more than 10 m/s - below minus 20 °C), descents into aggressive liquids (oil and petroleum products, domestic waste water), descents in conditions of contamination of the water area and in conditions of exposure to ionising radiation sources, descents in mountain conditions, descents into solutions of increased density, mine workings of shafts and tunnels, liquids with high and low temperatures, descents into narrow, restricted-confined or cramped places, descents at extreme outdoor air temperatures, descents into vessels with drinking water, descents at a current speed above 1.0 m/s, an underwater visibility radius of less than 0.1 m or the absence of underwater visibility, in conditions of limited visibility near the water surface (fog, heavy precipitation, steaming), descents at a sea state above 3 points, descents in conditions of the habitat of dangerous marine animals.
136. The person in charge of diving work is responsible for studying the current hydrological and meteorological conditions on the surface and the environmental conditions, and the person in charge of the diving descent - for establishing the current conditions during underwater descents. The conditions under which diving descents are conducted shall be recorded in the diving work log.
137. Descents in self-contained diving gear are permitted in normal and complicated conditions based on the results of the risk assessment and after measures have been taken to reduce or eliminate them. Descents in difficult and special conditions shall be performed in the hose configuration of the gear with a cable-hose bundle. Descents in special conditions shall be performed in the hose configuration of the gear with a cable-hose bundle and an emergency air supply. During the conduct of diving descents, other conditions or factors affecting their conduct may arise, which include water salinity, an underwater current, the degree and nature of fouling of the elements of structures, electromagnetic waves and lightning discharges.
138. On the day of a diving descent, divers are released from heavy physical work for a period, the duration of which depends on the depth of the forthcoming submersion, the working conditions, the duration of the work on the bottom and its nature. The duration of the time for which a diver is released from work before diving descents underwater is defined in Appendix No. 8 to the Rules. During the period of the diver's release from work, the performance of work on the preparation and operational check of the diving gear, the performance of the duties of an attending diver that do not involve heavy physical load, and the conduct of a medical examination are permitted. For the performance of heavy physical work, supporting personnel shall be appointed from among the workers participating in the conduct of diving descents or divers whose descent is not planned for that day.
139. The duration of the daily rest between shifts shall be twice the duration of the work. A shorter rest duration (but no less than eight hours) is permitted only in an emergency situation (emergency and rescue work).
140. Workers performing work in the cold season in the open air or working in unheated enclosed premises shall be provided with special breaks for warming and rest, which are included in the working time. The employer shall provide the equipping of premises for the warming and rest of the workers. The employer shall equip, in accordance with the established norms, sanitary and welfare premises, premises for taking meals, resting during working time and warming, places for dressing and undressing divers and for drying clothes and footwear, and shall provide for the possibility of supplying drinking water.
141. After a diving descent, the diver is released from all types of work not relating to diving descents, for the restoration of working capacity, for a period of time the duration of which, depending on the depth of the descent and the nature of the work on the bottom, is determined in accordance with paragraphs 142 - 163 of the Rules.
142. The total time of a diver's stay in conditions of increased pressure of the (water, gas) environment (hereinafter - under pressure) within a day (24 h) shall not exceed 6 h (the total time under pressure within a day equals the sum of the time of submersion, stay on the bottom and decompression in all descents performed by the diver during the work shift). In this case, the next descent is permitted no earlier than 12 h after the end of the last descent in the work shift. The duration of the work shift is no more than 8 hours and is determined based on the results of the special assessment of working conditions. In special cases, where the total time of a diver's stay under pressure within a day is from 6 to 10 h, the next descent is permitted no earlier than 24 h after the end of the current descent. If the total time of a diver's stay under pressure within a day has exceeded 10 h, then the next descent is permitted no earlier than 48 h after the end of the current descent. Based on the conditions of performance and the nature of the diving work, the work and rest regime of divers may be changed. The person carrying out production control during the conduct of diving descents is responsible for compliance with the work and rest regime of divers. When conducting deep-water diving descents and descents by the long-term stay method under increased pressure, the duration of work shifts, as well as the work and rest regime, is determined for each case separately during the planning of the work.
143. Before an underwater descent, the diver shall be provided with rest (Table 1).
144. Full rest of divers means their release from all types of work. During this period, only a medical examination, taking meals, and the preparation and operational check of gear are permitted.
145. The duration of the time of release from work before a descent may be changed taking into account the nature of the work, the diver's conditioning, as well as in special conditions of descents.
146. On the day of a descent, divers shall be released, 1 h before the start of full rest, from heavy physical work (loading and unloading, lifting and carrying heavy objects).
147. When round-the-clock work is conducted in shifts, each diver shall have, before a descent, no less than 8 h for sleep.
148. The maximum permissible time of divers' stay on the bottom is specified in the decompression regimes.
149. After an underwater descent, divers are provided with rest (Table 2).
150. After full rest, divers shall be released until the end of the working day from the heavy physical work specified in paragraph 138 of the Rules.
151. For the acquisition of the initial conditioning of divers to the factors of a diving descent, the latter shall be carried out sequentially to depths of 5 - 20, 21 - 40, over 40 m, with an exposure on the bottom of no less than 20 min. The number of descents to each depth is determined for each diver by the person in charge of diving descents, based on the level of the diver's professional training and the individual characteristics of his body.
152. In the event of long breaks between underwater descents, for the restoration of conditioning, Table 3 shall be followed.
153. Where it is necessary for a diver to descend to a depth exceeding that already attained, Table 4 shall be followed. The actions for the restoration of divers' conditioning, depending on the break between underwater descents and the procedure for admitting divers to descents to depths greater than those attained, may be adjusted and changed depending on the individual characteristics of the divers' bodies where it is possible to conduct the relevant examinations and functional tests at a medical organisation.
154. For the acquisition of initial resistance and the maintenance of resistance to the narcotic effect of nitrogen and other factors of increased pressure, divers and diving specialists admitted to the provision of first aid in the event of illnesses and the receipt of injuries connected with the professional activity of divers under increased pressure, as well as diving physicians (paramedics), shall carry out training descents in a pressure chamber.
155. Persons participating in training descents in a pressure chamber are released from heavy work 1 hour before the descent. After the descent, they are provided with full rest for 2 hours, and they are released from heavy physical work until the end of the working day. For 2 hours after the descent, they shall remain near the pressure chamber.
156. When travelling by air transport before and after diving descents, the time intervals shall be observed in accordance with Table 5.
157. The procedure for admitting divers to descents depending on the breaks between descents by the short-duration dive method is in accordance with Table 6.
158. If, during the period between descents to the attained depth, a diver made descents to lesser depths, then these descents shall be counted as the corresponding training descents required for the admission of the diver to descents by the short-duration dive method to the attained depth.
159. Where it is impossible to conduct descents in the sea, to maintain divers' conditioning to the factors of the hyperbaric environment, it is permitted to conduct descents under a pressure corresponding to the attained depth with an exposure on the bottom of up to 30 min, but no more than once within 3 months. One day before submersion to the attained depth, one descent shall be conducted in the sea to depths of 10 - 20 m to practise the skills of using the diving gear and providing first aid to a diver in the event of illnesses and the receipt of injuries connected with the professional activity of divers. During descents in the pressure chamber, the gas environment in it is created in a manner analogous to the methodology for its creation in the DB during descents by the short-duration dive method.
160. The procedure for admitting divers to descents depending on the breaks between descents by the long-term stay method is in accordance with Table 7.
161. If, during the period between descents, a diver participated in descents to the attained depths by the short-duration dive method and the breaks between these descents do not exceed 30 days, then these descents are counted as the corresponding training descents required for admission to work at the attained depths by the long-term stay method.
162. In the event of a break between descents of more than 4 months, the initial depth for conducting training descents, the programme for mastering the depth and the sequence are determined by the diving specialist and the diving physician, based on the previous work experience of each diver individually and knowledge of the materiel of the diving hardware.
163. Where it is necessary to conduct emergency restoration and emergency rescue work, as well as urgent work to prevent accidents on underwater oil and gas equipment, in the event of a break between descents of more than 4 months, the compression of divers to the working depth is permitted with stops: 100 m and thereafter every 50 m, with an exposure at each of 2 - 4 hours. This method of compression is permitted after the performance of training descents in the sea by the short-duration dive method on KGS to a depth of 100 m.
164. The work of one diver underwater for more than 4 hours during a work shift (8 hours) and for more than 6 hours within a day (24 hours) shall not be permitted. Where this condition is observed, the next diving descent is permitted no earlier than 12 hours after the end of the previous diving descent.
165. The nutrition of descending divers shall be organised so that each diver has the opportunity to receive hot food. The general principles of rational nutrition shall be observed, taking into account the professional features of diving labour. The food shall be high in calories and not abundant, without the inclusion in the diet of products that cause increased gas formation in the intestines. When staying in the pressure chamber under increased pressure for a duration of more than 4 hours and during therapeutic recompression, hot food and drink are passed into the pressure chamber.
166. For the purpose of strengthening health, compensating for energy expenditure and preventing occupational diseases, divers and other workers performing descents underwater or in a pressure chamber are issued with therapeutic and preventive nutrition on the days of the actual performance of diving work, regardless of the duration of the descent and the depth of submersion.
167. Divers' descents to previously attained depths after a long break in work, or to depths exceeding those previously attained, shall be conducted by divers only after the performance of training descents in accordance with Appendix No. 8 to the Rules. During the inter-descent period, in the absence of diving work, for the purpose of maintaining the state of conditioning to the effect of mechanical pressure, the narcotic effect of nitrogen and the factors of decompression, as well as for the acquisition of initial resistance of the body of divers, diving specialists and diving physicians (paramedics) to nitrogen narcosis and other hyperbaric factors, training descents in a two-compartment pressure chamber shall be planned. One compartment (the fore-chamber) of the pressure chamber shall always be ready for locking. For the maintenance of the skills of performing work and actions in the event of abnormal and emergency situations, training diving descents in the water shall be conducted.
168. The initial gaining of depth in the water shall be performed sequentially with an interval of no more than 10 m; when previously attained depths are re-gained by experienced divers, the interval may be 20 m. The gaining of depths in the pressure chamber may be carried out with an interval of no more than 20 m in the range of 40 - 100 m. The planning of training diving descents shall be performed in such a way that the break between the descents of each diver does not exceed 14 calendar days.
169. The organisation of actions for providing assistance to a diver in the event of an abnormal or emergency situation shall be an integral part of the organisation of diving work - as an element of the labour protection management system during the conduct of the organisation's diving work. The actions shall be of a practical and feasible nature, aimed at the planning of specific actions in the event of abnormal and emergency situations, the provision of the work with the necessary resources for providing assistance, and shall ensure accessibility to the place of provision of medical assistance in full and in the shortest time.
170. In the event of an abnormal situation or an unfavourable change in the circumstances that may lead to the occurrence of an emergency situation, the person in charge of the diving descent shall act independently, adhering to the actions provided for in advance during planning and in keeping with the circumstances, having immediately notified the person in charge of diving work of what has occurred.
171. The person in charge of the diving descent shall terminate the diving descent in the following emergency situations: (a) if the supply of breathing air to the diver has ceased or been disrupted; (b) if information has been received from the working diver about mechanical damage and disruptions to the normal operation of individual parts of the diving gear and hardware; (c) if the main and reserve two-way voice communication with the working diver has failed and it is not possible to restore it, or no reply has been received from the working diver to a twice-repeated enquiry via voice communication and then via the cable-hose bundle (signal line, signal cable); (d) if it has not been possible to disentangle (free) the cable-hose bundle, diving hose, signal line or signal cable that have become entangled (jammed), together or separately; (e) if the working diver has been thrown to the surface or has fallen (dropped) to depth.
172. Upon receipt of an emergency signal from the working diver or the occurrence of an abnormal or emergency situation, a command to stop work shall be given immediately, the emergency situation shall be announced, and, based on it, a command shall be given to descend the standby diver, a command shall be given to prepare for the raising of the diver, and the raising of the diver shall be commenced.
173. Preparation for the actions for providing assistance in the event of an abnormal or emergency situation with a diver is mandatory for the managerial, diving and supporting personnel involved in participation in the performance of diving work.
174. An organisation performing diving work shall provide for the rendering of assistance to an injured diver in a pressure chamber, including the conduct of therapeutic recompression.
175. Diving work at depths of more than 12 m, and training and experimental descents regardless of the descent depth, shall be conducted in the presence of a diving pressure chamber ready for immediate use and located at the place of the conduct of the diving work.
176. In the absence of a pressure chamber at the place of the conduct of diving work, the employer shall provide for the transportation of a diver requiring the urgent conduct of therapeutic recompression to a medical organisation or another organisation that has an approved and operationally ready pressure chamber, with which an agreement on the rendering of assistance to an injured diver has been concluded. The person in charge of diving work and the person in charge of diving descents shall know the exact address, telephone and routes to the nearest pressure chamber that is in a state of readiness.
177. The conditions regarding the time of delivery of an injured diver are established based on the results of the risk assessment and shall be reflected in the documents for planning actions in the event of abnormal and emergency situations. Based on the results of the risk assessment, where there is a high probability of the occurrence of an accident or emergency case, in the absence of a pressure chamber at the place of the conduct of diving work and where the time of evacuation of an injured diver to a pressure chamber is more than 120 minutes, the employer shall provide for the evacuation of the injured diver using a transportable (portable) pressure chamber.
178. For the performance of diving work on a permanent or temporary basis, a diving station is formed, which is the main production unit of a structural subdivision of the organisation, to which the functions of the performance of diving work are assigned. The main task of the production activity of the diving station is the performance of diving work characteristic of the given organisation at one work site (area) of the production territory.
179. Divers are distributed by the employer among diving stations (diving groups). During the performance of diving work, a specific production site and a defined type and nature of work at the production activity site are established for each diving station. Diving gear, diving hardware, means of supporting diving descents and other equipment or property necessary for the performance of diving work are assigned to the diving station.
180. At each diving station there shall be no fewer than two admitted persons in charge of diving descents. Where there is one diver at a diving station who is admitted to being in charge of diving descents, he may not descend underwater.
181. In an organisation where four or more diving stations are provided for by the staffing schedule, a diving service is created.
182. During the performance of diving work, the workplace of the diving station personnel is the diving complex, the diving post or the production area (the work site at the diver descent point), as well as the places of storage, preparation for descents (servicing after descents), maintenance and repair of the diving hardware. The workplace of the working (descending) diver is the object of the forthcoming work (the performance of the task), located underwater (in conditions of increased pressure of the surrounding environment). The workplace of the diving station personnel may be stationary or non-stationary.
183. Fixed workplaces include production premises for carrying out diving descents and work, such as a diving post, a fixed, mobile and portable diving complex, a diving hyperbaric complex, a training complex, a technical base, a rescue post, a ship's post and other production (service) premises, at the locations where diving work is carried out.
184. Non-fixed workplaces include production sites (work areas) located at the descent site or in the immediate vicinity of the site where diving descents are carried out, at which the workplaces are equipped temporarily or only for the period during which the work is carried out, a non-specialised floating craft, a small-size craft or a work area with a set of diving equipment, diving hardware, diving descent support means and process equipment.
185. The non-fixed workplaces of the personnel of a diving station shall comply with the requirements for the equipping of a production site or work area at the diving descent site and are governed by these Rules and by the local acts of the organisation, proceeding from the need to observe the requirements of labour protection and health of the personnel.
186. When organising workplaces, the safety of workers is ensured by: 1) protecting workers from the hazards created by the operation of vessels (boats, floating structures and objects), by lifting mechanisms and by operational modes at the work site; 2) protecting workers from the hazards during production activity: falling into the water, falling from height, electric shock, the availability of passageways for the unimpeded movement of the diver and of the persons supporting him, protection against slipping and against the sudden action of ropes and cables working under load, and other hazards depending on the specific conditions of the production activity; 3) determining the hazardous and working zones, the safe distances to the sources of hazard under water and on the surface, and the conditions upon the occurrence of which diving work is suspended or prohibited; 4) the rational choice of the diving descent site and the rational placement of diving hardware, process equipment and diving descent support means at the diving post and at the descent site; 5) the safe handling of diving hardware, process equipment and diving descent support means, including tools, devices, materials, blanks and raw materials; 6) the equipping of places for checking diving hardware, for changing clothes, for rest and for warming, and, where necessary, lighting and fencing; 7) the use of individual and collective protective equipment and the protection of workers against unfavourable environmental factors; 8) establishing interaction between all participants in the diving work on whom the safety of the work may directly or indirectly depend; 9) a system for monitoring the preparation of workplaces and checking readiness for work.
187. The workplaces for carrying out diving work shall be prepared and checked before the commencement of the work. In doing so, the completeness of the workplaces in terms of labour protection and safe operation instructions, process cards for the types of work and other documentation provided for carrying out diving descents and work is checked. Before the work, the following is checked: the provision of the workplaces with safety devices (the presence of earthing, warning notices and safety signs, locking devices, interlocks, retainers, instruments for monitoring hazardous factors, alarms, plugs and others), the serviceability of diving hardware, process equipment, tools, rigging and devices, sufficient lighting at the workplaces and at the diving descent site, and the presence and reliability of communication between all participants in the work. The valves, gate valves or switches of the divers' life-support systems, their colour and arrangement shall ensure unambiguous identification of and unimpeded access to them, including in an emergency situation involving a diver. Cylinders with supplies of air and breathing gas mixtures shall be filled to the working pressure, and compressors shall be ready for operation. When placing cylinders, vessels operating under pressure and decompression chambers, the temperature regime at the places of their installation or placement shall be monitored, allowing neither overheating nor overcooling. The diving equipment, hardware and diving descent support means shall be placed at the diving post in working condition in such an order that they do not hinder the work of the persons supporting the diver's descent and do not create the possibility of accidental use of unserviceable equipment or of equipment not prepared for operation. The workplaces at the diving station shall be free of foreign objects. Cluttering them with equipment not related to diving descents shall be prohibited.
188. Decks, floors, coverings, flooring and other surfaces at the diving descent site shall be non-slip. In the zone of passage or presence of the support personnel there shall be no ropes, cables or working lines under load whose sudden rupture may cause injury. The places of passage (descent, ascent) to the place of the immediate work (the place for supporting the diver's descent) shall be equipped with ladders, stairways, gangways, gangplanks, guardrails, nets and rescue equipment protecting against falling into the water or serving for rescue in the event of a fall. Places hazardous for the passage and (or) presence of people shall be fenced with ropes, warning plates or warning tape, and, when working during the hours of darkness and in conditions of insufficient visibility, shall be equipped with signal lamps and (or) safety signs with a reflective coating.
189. The presence of unauthorised persons and observers at the divers' workplace during diving work shall not be permitted. The workplaces shall be fenced off against unauthorised access (passage), and, in the event of the unavoidable presence of unauthorised persons in the immediate vicinity of the descent site, they shall be provided with standby PPE.
190. For the storage of oil-soaked, spirit-soaked and contaminated wiping materials, separate containers (special metal boxes with lids, sealed bags) shall be provided, which at the end of the working day shall be removed to specially designated places or disposed of.
191. During descents in the hours of darkness, underwater and above-water artificial lighting is used. On the surface, the following are illuminated: the places of preparation for diving work and diving descents, the control instruments of the devices supporting the descent and the performance of the work, and the surface of the water above the site of the diver's descent and work.
192. Diving work shall be carried out in conditions ensuring the protection of all personnel of the diving station at the descent site against precipitation, wind, low or high temperatures and other environmental influences affecting the safety and quality performance of the duties of the support personnel. When organising non-fixed workplaces and working outdoors, dry premises (cabins, tents) shall be provided for carrying out the working check of diving equipment, for breaks in the work, for drying clothes, and for warming and rest of the personnel involved in the work.
193. When performing diving descents and work at low and sub-zero outdoor air temperatures, heated premises (cabins or tents) installed at the descent site shall be used for dressing and undressing divers, and, in the case of descents from ice, over the ice holes or beside them. To protect the personnel of the diving station and the divers during the period of dressing and undressing against the effect of wind and precipitation and direct sunrays, the installation of protective enclosures (awnings, canopies), unheated tents or cabins shall be provided for.
194. Workplaces where chemical air regeneration means are handled shall be equipped with supply-and-exhaust ventilation, and rest areas shall be equipped with exhaust ventilation or an air conditioning system. The personnel of the diving station shall be provided with individual and collective protective equipment.
195. When performing diving work at operating facilities, the personnel of the diving station shall be familiarised with the internal regulations, with the hazards arising during production activity, and with the actions to be taken upon alarms and signals at the facility.
196. When equipping workplaces for performing diving work in ports, on hydraulic structures and at industrial facilities, the scheme of the routes of movement of vehicles and pedestrians across the territory of the facility shall be clarified with the owner of the facility. Hatches, wells, pits, openings, trenches, and also places and areas of the territory presenting a hazard to the personnel of the diving station and to the movement of vehicles, shall be closed off or fenced. The scheme for the placement of the diving station and the installation of removable ladders and (or) launch and recovery devices on the territory of the port, hydraulic structure or industrial facility shall be approved by the person in charge of the diving work or the person in charge of the diving descents. The descent and ascent of divers by means of fixed stairways and rung ladders installed from the water side on berths and hydraulic structures shall not be permitted, except in cases where such a method of descent (ascent) is provided for by the design documentation of the hydraulic structure.
197. When performing diving work from vessels and carrying out operations in the roadstead, at sea and in the shore-fast ice, the requirements of the rules on labour protection aboard vessels of the maritime and river fleet, approved by the Ministry of Labour and Social Protection of the Russian Federation in accordance with sub-clause 5.2.28 of the Regulation on the Ministry of Labour and Social Protection of the Russian Federation, approved by Government Resolution of the Russian Federation No. 610 of 19 June 2012 (Collected Legislation of the Russian Federation, 2012, No. 26, Article 3528), shall be observed. Mooring to vessels, berths and other objects from which diving work is being conducted, without the permission of the person in charge of the diving descent, shall be prohibited.
198. Diving equipment shall be donned on the diver in accordance with the operating instructions for the equipment and may differ depending on the diving equipment used, the conditions and nature of the work, and also the experience and physical capabilities of the diver. The procedure for donning shall be included in the instruction on the safe operation of diving equipment developed at the organisation.
199. A safety system (harness system) ensuring the lifting of a diver in distress in a vertical position shall be donned on the diver. The safety system may be integrated with the harness system and with the system for placement (release) of diving weights. In individual cases, a safety belt (chest harness) and a signal line (signal cable) may be used, if the type of equipment used does not permit the use of a safety system or the expediency and sufficiency of these means has been confirmed. Descents from a berth, from the side of a vessel, from hydraulic structures, in confined conditions and in restricted-enclosed spaces without a safety system shall be prohibited. When a safety belt is used, the signal line or signal cable shall be secured to the belt donned on the diver's waist. When hose-supplied equipment with an open breathing circuit is used, a harness system is used for securing the cable-hose bundle, the hose-cable and the signal line by means of a carabiner. The performance of diving descents without a safety system or a signal line shall be prohibited, unless this is provided for by these Rules and instructions and confirmed by a risk assessment before the descents.
200. When a diver works under water in a swimming set of diving equipment (a set of equipment used for swimming under water, which includes foot fins), instead of a signal line the use of a control line with a buoy to indicate the diver's location is permitted. The use of inflatable means as a buoy shall be prohibited. The length of the control line shall exceed the depth in the area of the diver's swimming by 20 per cent. Swimming of a diver with a control line is permitted in normal conditions at shallow depths and shall be supported by a floating craft. A diver may descend without a signal cable (signal or control lines) provided that a cable-hose bundle with a breaking force of not less than 200 kgf is used.
201. Diving equipment shall ensure the continuous supply to the diver of air or a breathing gas mixture (hereinafter - BGM) in the required volume, taking into account the conditions of the descents and the nature of the work performed, and also the diver's level of training. During working descents, the pressure of air (oxygen, BGM) in the cylinders of the apparatus may be 10 per cent lower than the working pressure. During educational and training descents, the pressure of the main supply of air (oxygen, BGM) in the cylinders shall be not less than 100 kgf/cm2. The pressure of the reserve supply of air (oxygen, BGM) shall be not less than 90 per cent of the working pressure. The estimated time of the diver's stay under water in self-contained equipment is limited taking into account the supply of air (oxygen, BGM) for breathing according to the actual pressure in the cylinders and taking into account the capacity of these cylinders. The estimated time of the diver's stay under water in hose-supplied equipment is limited taking into account the possibility of carrying out decompression in the water in the event of cessation of the air supply from the surface. Upon completion of dressing the diver in ventilated equipment or in hose-supplied equipment with an open breathing circuit, before the helmet is donned on the diver, air (BGM) shall be supplied into it.
202. The main method of entry into the water shall be a diving ladder, a diving stage and (or) a diving bell. The choice of the rational method of immersing the diver, and the expediency and sufficiency of the means for descending divers, is determined by the person in charge of the diving descents on the basis of the conditions of the diving descents and the nature of the diving work, the descent methods applied and the diving hardware used, taking into account the provision of a safe exit of the diver from the water and the possibility of rendering assistance to the diver in the event of an abnormal or emergency situation. Immersion into the water without means of supporting the diver's immersion shall be prohibited, except for descents from the shore and descents during rescue work. In doing so, additional safety measures shall be observed: (a) the absence of obstacles on the path of entry into the water; (b) the absence of obstacles under water; (c) measures to prevent the dislodging or loss of the mask, helmet or demand regulator are provided for.
203. Before diving descents, additional means of supporting the diver's immersion and transfer to the work site are installed: descent, guide, travelling, keel, auxiliary and working lines, marking and other lines. Ballast is secured to the descent line, the mass of which is chosen on the basis of the condition of ensuring the retention of the diver on the descent line depending on the type of equipment applied. The lines shall be whole, without splicing sections, and their circumference is chosen on the basis of the conditions of convenience of the diver holding them in the hand with a full grip.
204. When carrying out diving descents from a vessel (a boat, a floating structure or object, offshore drilling platforms), a berth, a dam and other hydraulic structures, the use of a diving ladder for the descent is possible where the height of the descent site above the water surface is not more than 3 m. Where the height above sea level is more than 3 m, diving descents are carried out: (a) in a diving stage (diving bell), using a launch and recovery device meeting the safety requirements for moving people; (b) using a harness system and anchor devices meeting the safety requirements for moving people; (c) from another vessel (a boat, a pontoon, a dinghy, a floating craft or other floating objects) with a lower freeboard height above sea level.
205. Depending on the nature of the work and the result of the risk assessment, and also where the height of the descent site above sea level is from 2 to 3 m, the presence at the descent site of a duplicate (reserve) means for the emergency lifting of the diver from the water in a vertical position shall be provided for.
206. When carrying out diving descents from the side of special vessels (boats) intended for carrying out diving work and equipped with regular places for the descent (ascent) of divers, the methods of immersing the diver into the water and of exit from the water, and of the emergency lifting of the diver, are established in the documentation on the use of the ship's diving complex (the performance of diving work from the side of the vessel). When carrying out diving descents into shafts, wells, hatches, chambers, water-pressure structures of limited diameter, compartments of sunken vessels, large-diameter pipes and other restricted-enclosed spaces, where the installation of ladders and launch and recovery devices is impossible, irrespective of the height above the water level, three-legged frames with an anchor device, tripods or other launch and recovery devices meeting the safety requirements for the descent (ascent) of people shall be used.
207. The immersion of a diver is permitted after: (a) the person in charge of the diving descent has personally ascertained that the conditions of the diving descents permit the descent to commence and that the descent is safe; (b) the preparatory actions have been carried out and the risk assessment has been performed; (c) the signals of diving work being carried out have been displayed (hoisted) in accordance with the International Regulations for Preventing Collisions at Sea in force or with the rules for the navigation of vessels on inland waterways. The person in charge of the diving work shall personally ascertain that carrying out the diving work is safe and give permission to the person in charge of the diving descents to commence the diving descents. The start of a diving descent is deemed to be the full immersion of the diver under water or the beginning of the increase of pressure.
208. After receiving permission to immerse from the person in charge of the diving descent, the diver commences the immersion under water. Having immersed under water, the diver shall ascertain the proper operation of the equipment, the normal supply of air, the tightness, the presence of two-way communication and the buoyancy, and report the results to the surface. Further immersion of the diver is possible only after the person in charge of the diving descent has ascertained the tightness of the equipment and has given the command to continue the immersion. During descents in a swimming set of equipment, the diver's buoyancy shall be brought to a slightly negative buoyancy. The required buoyancy of the diver is achieved by changing the mass of the weights and is determined by a test dive of the diver. When a buoyancy compensator is used, the buoyancy is regulated by the diver while located at the water surface at the descent site. The person in charge of the diving descent shall monitor the buoyancy of the working diver. The descent of a diver under water with unadjusted buoyancy shall be prohibited.
209. Upon a sensation of pressure on the ears and the area of the paranasal sinuses during immersion, the diver shall suspend the descent and take measures to equalise the pressure in the paranasal sinuses by an available method. If the sensation of congestion does not pass, the diver shall rise by 1 - 2 m and repeat these actions again. Upon a repeated sensation of pressure on the ears and the area of the paranasal sinuses, the diver shall stop the descent and go up to the surface.
210. A diver located in the water shall have the possibility of switching to breathing from the emergency (reserve) supply of air (BGM) sufficient for going up to the surface (switching to breathing from the atmosphere) in observance of the decompression regimes. In individual cases, an additional alternative source of air supply may be used. When ventilated diving equipment without a reserve supply of air is used, additional measures to ensure the safety of the diving descents shall be taken.
211. Changes in the situation (the lowering or lifting of loads, tools, equipment or materials, a change in the length of the mooring lines or anchor chains, the switching on of individual systems, a change in the regime of the supply of air or water and other actions which may affect the safety of the diver) are carried out only with the permission of the person in charge of the diving descent and after the working diver has gone up to the surface.
212. A diving descent shall be immediately terminated in the following cases: (a) at the demand of the diver working under water; (b) at the demand of the master of the vessel, the person in charge of the diving work or the responsible executor of the diving work, and also of the owner of the facility, transmitted through the person in charge of the diving work; (c) at the demand of the operator of the dynamic positioning system or upon the activation of the alarm; (d) loss of communication with the diver; (e) cessation of the supply of air (gas mixture) to the diver, breakdown or malfunction in the air- or gas-supply system; (f) deterioration of the weather conditions (intensification of wind and waves) or the onset of other critical conditions established before the descents; (g) the occurrence of an abnormal or emergency situation involving the working diver; (h) impairment of the reliability of the anchorage or holding of the vessel from which the diving work is being carried out; (i) violation of the safety of navigation by outside vessels (craft) in the diving work zone; (j) a change in the operating regime of the facility at which the work is being carried out; (k) by decision of the person in charge of the diving descent; (l) upon the detection of unaccounted-for risk factors or insufficiency of protective devices and appliances.
213. The person in charge of the diving descent shall continuously maintain two-way communication with the working diver, either personally or through the diver providing communication support, from the moment of the start of the diving descent until his exit from the water to the surface. As the main type of communication, two-way voice communication with the diver shall be ensured. Commands (messages, queries) to the divers, and also reports from the divers, shall be concise, easily pronounceable, distinct, perceptible and unambiguous in meaning.
214. Giving two commands simultaneously to divers located under water shall be prohibited. Commands given to a diver shall be repeated back by him. When commands are given to several divers working under water, they shall be assigned a conventional number for the descent, and the giving of commands to the next diver may be carried out after confirmation of receipt of the command by the previous diver. As backup communication, the use of signal communication for the transmission of conventional signals by means of the diver's cable-hose bundle, the signal cable or the signal line when a diving hose is used is permitted.
215. In individual cases, when performing diving descents where the use of communication means is impossible on the basis of the conditions of immersion or is technically impossible, alternative methods of maintaining communication with the diver using visual or technical contact with the diver shall be organised: (a) maintaining visual contact between divers; (b) maintaining visual contact using a remotely operated unmanned underwater vehicle; (c) the use of conventional sound signals; (d) maintaining technical contact using low-power hydroacoustic means. In this case, an instruction on the organisation of the safe conduct of diving descents taking into account the existing features shall be developed at the organisation. Underwater-engineering diving work and other diving work involving the switching on or off of process equipment without two-way voice communication with the diver shall be prohibited.
216. For the transmission of conventional signals (upon the failure of the main and backup voice communication), the slack of the cable-hose bundle (signal line) shall first be taken up, and then the signals shall be transmitted distinctly by vigorous movements. In doing so, it shall be borne in mind that conventional signals in a current are noticeably distorted by the constant vibration of the signal line and its large sag. Each signal shall be repeated (duplicated) by the person to whom it is transmitted, with the exception of the alarm signal, upon which the diver shall be immediately lifted to the surface.
217. Divers shall know by heart the conventional signals used, transmitted by means of the cable-hose bundle (the signal cable, the signal and control lines), specified in Appendix No. 9 to these Rules, or by another means, using conventional visual or light signals or tapping tables.
218. Upon loss of communication with the working diver, the diving descent shall be suspended and a command shall be given for the urgent preparation of the standby diver. Having received no reply from the working diver to a query repeated twice by any available means of communication, the person in charge of the diving descent gives the command to prepare for lifting the diver to the surface, taking into account the decompression regime, and for the descent of the standby diver.
219. Where it is impossible to restore communication with the diver in distress during the lifting, he is lifted without stops irrespective of the depth of immersion, and at the same time preparations are made to render him assistance in the decompression chamber. The lifting of the diver in distress shall be carried out only when he is able to move freely under water. In the event that free movement under water of the diver in distress is impossible, the standby diver shall be immediately lowered under water to render assistance to the diver in distress.
220. Communication with a diver who breathes breathing mixtures containing helium, which distorts speech, shall provide for equipment for the processing (correction) of speech. Communication with a diver located in the decompression chamber shall be maintained by telephone. Upon the failure of the telephone, communication with the person located in the decompression chamber is carried out by tapping conventional signals with a wooden mallet (a serving mallet). A table of the conventional signals shall be placed on the internal and external surfaces of the decompression chamber.
221. The working diver shall be warned of the start of his lifting, except in cases of lifting at his own demand, not less than two - three minutes in advance. Having replied to the signal, the working diver shall stop the work, check the clearness of his cable-hose bundle (signal cable, signal line, diving hose), stow the tools at the workplace or pass them up, approach the descent line (diving stage) and, having taken it in his hands (having positioned himself on the stage), give the signal for lifting.
222. The speed of lifting the diver to the first stop or to the surface is determined in accordance with the chosen decompression regime. During ascent, the diver shall not overtake the air bubbles issuing from the breathing apparatus and shall not hold his breath. In the event of an involuntary holding of breath (a spasm, a cough), the ascent shall be stopped for that time. The independent ascent of a diver from any depth shall be prohibited, except in cases where the descents are carried out in swimming sets of equipment and in the event of an emergency situation. During the lifting of the diver, measures shall be taken ensuring control over the process of lifting the diver and the prevention of the independent ascent of the diver in violation of the chosen decompression regime. The ascent of a diver by means of the lifting force of the buoyancy compensator shall be prohibited. Upon the occurrence of a threat to the diver's life or the absence of a reply from the diver to a repeated query about his well-being when the means of communication are serviceable, he is lifted to the surface without observance of the working decompression regime and is immediately placed in the decompression chamber for therapeutic recompression.
223. The lifting of a diver from depth is carried out in accordance with the tables of decompression regimes. The tables for choosing decompression regimes during descents using air for breathing are placed in Appendix No. 10 to these Rules. The choice of the working decompression regime is made by the person in charge of the diving descents, except in cases established by these Rules. The choice of therapeutic decompression regimes is made by the diving doctor (paramedic). Where a diving doctor (paramedic) is present at the site where the diving descents are carried out, the choice of working decompression regimes is entrusted to the doctor (paramedic).
224. The undressing of a diver is carried out in the order established by the person in charge of the diving descent, after the diver's exit from the water and the diver's taking up of a stable position. The undressing of a diver, in the absence of disturbance of the water surface, may begin on the ladder only after the diver's switching to breathing atmospheric air, provided that measures are taken to prevent the diver falling from the ladder. In doing so, the person supporting the diver's cable-hose bundle (signal cable, signal line, diving hose) (hereinafter - CHB) shall not have the right to let it out of his hands until the full exit of the diver and his taking up of a stable position. The undressing of a diver during mixed decompression regimes may be altered, proceeding from the need to observe the conditions for transferring the diver into the decompression chamber. In cold and inclement weather, the diver shall be undressed in premises located beside the descent site.
225. When carrying out diving work, lifting means are used for the descent, ascent and movement of divers. Lifting means used for the movement of divers, except in cases of emergency transportation, shall be intended for the movement of people and shall comply with the requirements of the regulatory requirements depending on the place of their placement (on a vessel, on the shore, at a hazardous production facility).
226. When moving a diver in a diving stage, the following safety requirements shall be observed: (a) the environmental conditions under which the lifting appliance carrying the diver may be moved shall be determined; (b) before each use, the lifting appliance, slings, ropes, shackles, hooks, safety latches and other load-bearing elements and rigging accessories shall be inspected; (c) the movement of persons in a diving stage or bell shall be carried out under the direct supervision of the person responsible for the safe performance of work using lifting appliances; (d) if accidental movements (swinging, turning, twisting) of the diving stage are possible, they shall be prevented by means of guy ropes or other stabilisation methods; (e) if the diving stage has to be moved (lowered) through hatches, openings or shafts of the vessel, additional safety measures shall be developed to prevent entanglement of slings and ropes and to reduce the risk of pinching, chafing and impacts; (f) the operator (crane operator) shall have sight of the lifting appliance carrying persons during the moving operation, as well as of the areas where lifting begins from the deck (shore, platform) and of the areas of entry into (exit from) the water, and these areas shall be free of any foreign objects and persons; (g) continuous two-way radio or telephone communication shall be provided between the operator (crane operator) and the diving descent supervisor; (h) the procedure for the exchange of signals between the operator (crane operator), the diving descent supervisor or the support diver designated to transmit signals and the persons in the diving stage shall be established (the recommended signals are provided in Appendix No. 11 to the Rules); (i) during the movement of the diving stage, the tools, materials and equipment located in it shall be securely fastened; (j) where the diving stage is used for work involving possible contact with the serviced surface of the structure (vessel, equipment), it shall be equipped with devices to reduce dynamic loads.
227. When moving a diver in lifting appliances, it shall be prohibited to: (a) use diving stages in strong wind, restricted visibility at the water surface, icing conditions, and also in any other conditions that may jeopardise the safety of persons and exceed the parameters established by the data sheet, regulatory documents, operating instructions and risk assessment; (b) carry out movement if there is a risk of collision of the lifting appliance with other devices, appliances and adjacent mechanisms; (c) carry out simultaneous movements of the launch and recovery device; (d) for a diver located in a diving stage, to stand on the handrails or guards of the diving stage and perform any work from such a position; (e) use any supports in the diving stage to increase the working area by height.
228. If the duties of the diving descent supervisor and of the person responsible for the safe performance of work using lifting appliances are not combined, there shall be continuous communication between them, and all movement operations shall be carried out only with the permission and on the commands of the diving descent supervisor. Launch and recovery devices (hereinafter - LRD), diving stages and diving bells that are in operation shall undergo periodic inspections and maintenance.
229. Before the commencement of diving work, warning signals shall be raised, and after its completion lowered: (a) during daylight hours - three shapes arranged in a vertical line in the most conspicuous place. The upper and lower of these shapes shall be balls, and the middle one a diamond. The shapes shall be black and of the following dimensions: a ball not less than 0.6 m in diameter, a diamond consisting of two cones with a common base (a cone not less than 0.6 m in base diameter and of a height equal to its diameter). The vertical distance between the shapes shall be not less than 1.5 m. On a vessel less than 20 m in length, shapes of smaller dimensions may be used in proportion to the dimensions of the vessel; (b) during the hours of darkness or in restricted visibility - three all-round lights arranged in a vertical line in the most conspicuous place. The upper and lower of these lights shall be red, and the middle one white.
230. If there is an obstruction to the passage of another vessel, a vessel engaged in diving work shall additionally exhibit: (a) two green all-round lights or two diamonds arranged in a vertical line - to indicate the side on which another vessel may pass; (b) two red all-round lights or two balls arranged in a vertical line - to indicate the side on which the obstruction exists; On a vessel 20 m or more in length, the vertical distance between the lights shall be not less than 2 m, and on vessels less than 20 m - not less than 1 m. If the dimensions of a vessel engaged in diving work make it impracticable to exhibit all the above shapes, then flag "Alpha" of the International Code of Signals shall be exhibited by day, made in the form of a rigid board not less than 1 m in height. Measures shall be taken to ensure the visibility of this flag.
231. Within inland waterways (rivers, lakes, canals, reservoirs) there shall be raised: (a) during daylight hours, two flags "Alpha"; (b) during the hours of darkness or in restricted visibility - two green lights arranged one above the other. The distance between the flags and lights shall be not less than: (a) on vessels 20 m or more in length - 2 m; (b) on vessels less than 20 m in length - 0.5 m. In both cases these signals shall be raised at the yardarm of the side at which the divers are working. If the dimensions of the serviced vessel, alongside which the diving boat is moored, are much greater than the dimensions of the boat, then the warning signals shall be raised on the mast of the serviced vessel in compliance with the necessary requirements. On the shore or on floating craft that do not have standard masts for raising signals, a temporary, clearly visible mast shall be installed. Warning signals raised on masts shall be visible around the horizon over 360°. If the installation of a single mast does not ensure visibility, or if diving work is carried out along a shoreline (mooring structure) more than 50 m in length, then 2 or more masts shall be set up, on which warning signals are raised, so as to ensure the visibility of the working area.
232. Diving work may be carried out from vessels, launches, floating structures and other floating objects (hereinafter - from vessels) that are secured to a mooring structure or the work site, or over the work site by means of anchors, mooring devices, roadstead equipment, or that are capable of being reliably held in a given position by means of a dynamic positioning system. Diving descents from a vessel that is making way or drifting shall be prohibited.
233. At sea, in the coastal zone, on inland waterways, in roadsteads and in water areas, work launches, support launches and small craft (including those launched from larger vessels) may be used for carrying out diving work, provided they are supported by a vessel or from the shore and that the diving work is carried out in the immediate vicinity, within the visibility zone and in weather favourable for the descent and recovery of the diver, as well as for the launching and recovery of the small craft. Self-propelled and non-self-propelled floating objects (floating cranes, barges, cable-layers, pipe-layers, dredgers, pontoons, boats), on which a diving station with a mobile or transportable diving complex or a rapid-deployment diving station may be temporarily placed, may be used for carrying out diving work. The smallest type of vessel from which diving descents may be carried out is small craft (ship's boats, boats, launches).
234. During the period of preparation for carrying out diving work from a vessel (floating object), the diving work supervisor shall satisfy himself, among other things, of the readiness of: (1) the ship's systems for lying, anchoring, mooring to roadstead equipment, mooring to the work site or holding at a given placement point by means of a dynamic positioning system (hereinafter - DPS) and for control of the vessel's position; (2) the ship's technical means for supporting diving work; (3) the diving equipment and gear.
235. When carrying out diving work, the results of the check of the vessel's readiness are recorded in the ship's log. When carrying out diving work from a vessel taken on lease, a statement of the vessel's readiness to carry out diving work shall additionally be drawn up, which is signed by the master of the vessel and the diving work supervisor.
236. When operating as part of a group of vessels, a joint manoeuvring plan shall be developed and agreed, specifying safe distances, restrictions on the performance of the work and on the conditions for carrying it out, the communication and interaction scheme, safety measures and other information affecting the safety of diving work during joint manoeuvring.
237. If two or more organisations carry out work simultaneously at a single work site (project), the control of the overall organisation of diving work at the site shall be performed by the customer of the work (owner of the site) or a person (organisation) authorised by it. The management structure and organisation of interaction, the responsibility of each participant, the delimitation of areas of responsibility and work sections, and the actions in the event of abnormal and emergency situations shall be communicated to all participants in the diving work before the commencement of work.
238. Diving work in a port water area is carried out with the permission of the harbour master on the basis of an application to carry out diving work or a diving descent. In the application the following are specified: the name of the organisation carrying out the diving work, the purpose of the work, and the date, time and place of the diving work. To ensure the safety of diving work, compliance by vessels with the rules of navigation near the places where diving work is carried out, and to inform organisations operating in the port, a general list of diving work is compiled, forming an appendix to the daily schedule of the disposition and movement of vessels in the port. Depending on the natural, climatic and hydrometeorological conditions, the features of the location, the intensity of navigation and other features of the port hydraulic structures, the harbour master may, by order (instruction, local regulatory act), establish additional requirements for carrying out diving work safely at port infrastructure facilities.
239. When diving work is carried out by the personnel of a temporarily placed diving station and (or) by a third-party organisation, a diving work supervisor shall be appointed by it. The duties and responsibilities for all stages of the diving work shall be distributed between the master of the vessel and the diving work supervisor, and shall be set out in writing and signed on a bilateral basis.
240. The master of the vessel is responsible for the safe lying, holding or performance of manoeuvres of the vessel at the place where diving descents and work are carried out, for continuous monitoring of the vessel's position and of the navigational situation in the area where the work is carried out, for the readiness of the vessel's technical means for carrying out diving work, and for the disposition and actions of the crew, and, where necessary, arranges the launching of a standby (work) launch. The diving work supervisor is responsible for the safe organisation and performance of diving work from the vessel and monitors the hydrological and meteorological situation in the work area. At the request of the diving work supervisor, the master allocates auxiliary personnel to support the diving descents.
241. Diving descents from the vessel may be commenced only after receipt of a readiness report from the diving descent supervisor. Where there are factors affecting the safe performance of the work, the master of the vessel, the diving work supervisor or the responsible performing authority, the representative of the customer on board the vessel or of the vessel's owner, and also the diving descent supervisor directly, may suspend or terminate descents from on board the vessel, and an entry shall be made in the vessel's log to that effect, stating the reason for stopping the diving work.
242. In coastal waters, in a roadstead, on inland waterways, in water areas or bodies of water and in ports, the means of diver descent is selected on the basis of the reliability of the lying or holding of the vessel at the place where the work is carried out, the height of the vessel's side or of the hydraulic structure, the conditions for carrying out descents, and the selected method of descent and recovery of the diver, taking into account the capabilities for recovery in an emergency situation. In the open sea, diving work from a vessel (floating object) shall be carried out using a diving stage or an open diving bell, with the exception of ship's work and emergency rescue work on the vessel's hull.
243. When carrying out diving work from a vessel using a moon pool, descents shall be carried out using a diving stage, diving bell or other devices intended for moving persons. When descending through a moon pool, actions shall be provided to prevent the accumulation on the water surface within the moon pool of any objects or ice that could impede the recovery of the diver from the water, including emergency recovery.
244. The use of the ship's cranes, beam cranes and winches to support the lowering of a diving stage and an open diving bell shall not be permitted, except for use in emergency situations when it is not possible to employ other means.
245. When carrying out diving work from a vessel equipped with a dynamic positioning system (DPS), the dynamic positioning system shall provide for redundancy in such a way that the failure of any element of the system required to hold the vessel at a given point does not lead to a loss of position. The maximum deviation from the positioning point shall be +/- 2 per cent of the maximum depth at which the diving descent is carried out. The DPS class of the vessel required for a specific operation, the critical excursion, the safe working distances and other factors that may affect the safety of carrying out diving work shall be based on an assessment of the risk of the consequences of a loss of position. The operating mode of the DPS shall correspond to the depth in the area where diving work is carried out and shall ensure the specified holding accuracy parameters. When carrying out diving work in shallow water, the following additional factors shall be taken into account: (a) the working range of the taut-wire method decreases significantly depending on the height of the attachment point; (b) acoustic positioning methods are most sensitive to distortions associated with external influences from the vessel; (c) the maximum movements of the vessel may exceed the specified parameters relative to the transponder beacons.
246. When carrying out diving work from a vessel equipped with a DPS, there shall be not less than two dynamic positioning system operators on board. While diving work is being carried out, the dynamic positioning system operator promptly informs the diving descent supervisor and other officials of the vessel's current position in accordance with the approved interaction scheme, while diving work is being carried out.
247. When carrying out diving descents from vessels equipped with a DPS, all ship's stations involved in carrying out the diving work shall be equipped with emergency indicator panels. Diving work is immediately terminated in the event of a failure of the vessel's dynamic positioning system. In cases where diving work is terminated, the recovery of the divers on board the vessel shall be ensured and measures shall be taken to prevent the occurrence of an emergency situation. Diving descents are resumed after the causes of the DPS failure have been eliminated and after the DPS checks provided for before the commencement of diving descents have been carried out.
248. In exceptional cases, movement of the vessel from the point where diving work is carried out is possible without recovering the divers to the surface. The use of such a method of movement is limited by the following conditions: (a) a change of course or position shall be carried out separately in stages; (b) the maximum amount of movement of the vessel on a given course shall be not more than 10 m per stage; (c) the maximum amount when changing the vessel's course is limited to a turn of not more than 5° relative to the selected centre of rotation per stage.
249. When moving the vessel without recovering the divers, the following safety requirements shall be met: (a) throughout the entire period of the vessel's change of position, the umbilicals of the divers, of the diving stages and of "wet"-type bells, and the load-bearing connections of the cargo anchors shall be kept under continuous control; (b) the divers shall be notified of the vector of the vessel's movement relative to the place of their underwater work occupied by them and shall have no obstacles to movement throughout the entire period of the vessel's change of position; (c) the determination of the vessel's position throughout the entire period of movement shall be carried out from several independent points; (d) the movement of the vessel shall be carried out at the minimum possible speed; (e) a change of the vessel's course and position shall not be performed simultaneously; (f) if it is necessary to change the vessel's course, the current position occupied by the diving stage or bell shall be selected as the point of rotation.
250. When carrying out diving work from a vessel equipped with a DPS, the working diver shall have a maximum umbilical (cable-hose bundle) length that is 5 m less than the calculated distance to the nearest azimuth thrusters and other hazardous zones. The standby diver and the in-water support diver shall have an umbilical length greater than the umbilical length of the working diver. The choice of the method of standby cover for the divers depends on the conditions for carrying out the diving descent, the nature of the work performed and the availability of personnel (divers), and shall be selected and calculated before the commencement of diving work. The method of standby cover for the diver may be active or passive.
251. In the case where the safe umbilical length exceeds the distance to the work site from the place of descent on the vessel or from the location of the diving stage (diving bell) at the bottom, measures shall be taken to eliminate the possibility of the umbilical entering the azimuth thrusters and other hazardous zones.
252. The specific features of carrying out diving work from a vessel equipped with a DPS in the specific conditions of the production activity shall be taken into account in the process flow chart for the performance of the work, the production planning documents and the instructions (guidelines, standards) developed by the organisation carrying out the diving work.
253. Diving descents from small and low-seagoing floating craft, ship's boats, launches and boats (hereinafter - small craft) are carried out during diving work when descents directly from the side of the vessel or from the shore (quay, hydraulic structure, shore platform) are impossible or inexpedient. Diving descents from small floating craft are limited to a sea state of not more than two points and a descent depth of up to 20 m. The decision to use small craft for diving descents is taken by the diving descent supervisor on the basis of the results of a risk assessment. In doing so, the following factors shall be taken into account: (a) the conditions for carrying out diving descents; (b) the type of diving equipment; (c) the safety of the diver's descent method and the possibility of exiting the water both independently and with the assistance of the support personnel; (d) the technical characteristics and capabilities of the craft; (e) the physical capabilities of the diver.
254. Diving descents from small craft shall be carried out with support for the operation of the craft from the shore or from a vessel (floating object). In doing so, the craft shall remain in the immediate vicinity or on the line of direct visibility, and two-way communication shall be arranged between them. When a diving station is placed on a small craft, there shall be not less than two persons on it who are authorised to descend under water. During diving descents from a craft operating at a distance from the vessel or shore, the diving descent supervisor shall be located on the craft.
255. The conditions under which the use of small craft for carrying out diving descents may be limited: (a) the technical characteristics of the craft (seaworthiness, stability, unsinkability, manoeuvrability) do not ensure that diving descents can be carried out safely and (or) that workers can remain on the craft in the specific weather conditions; (b) the limited capabilities of the craft for accommodating persons and cargo and the diving station, and insufficient working deck area; (c) increased risk of injury when working from the craft, when lowering persons into the craft or when exiting from it, or when launching or recovering the craft itself; (d) absence of navigation systems or their low accuracy; (e) the range of the communication equipment; (f) the power of the propulsor and the redundancy of the means of ensuring movement; (g) the absence on the craft of devices for the diver to hold himself unaided alongside and of means facilitating the recovery of the diver into the craft; (h) the absence of the possibility of rendering assistance in the event of an abnormal or emergency situation with the diver.
256. When using inflatable craft, unsinkability and stability shall be ensured in the event of damage to one compartment, taking into account the personnel and cargo (diving station) placed on the craft for the duration of the diving descents, and the craft shall be ready to get under way using oars and (or) a propulsor. On a craft with rigid sides, a means ensuring the unobstructed exit of the diver from the water, a small ladder or platform, shall be provided. Among the craft's personnel there shall be not less than one person authorised to operate the craft. The craft's personnel shall continuously monitor the diver's location by any available means while diving descents are being carried out.
257. The descent of a diver from a small craft is carried out by ladder, by falling (tipping) backwards over the side from a seated position on the side or on the transom board (for a ship's boat without a rudder), or by a "side step", in compliance with the necessary safety measures (body posture, securing of items of equipment, absence in the water of foreign objects and persons). When carrying out diving work from a small craft, the additional harmful and hazardous production factors are: (a) injury from impact against the rudder and (or) propulsor; (b) the diver, items of diving equipment, the umbilical or the signal line being drawn under the propeller; (c) uncontrolled ascent of the diver under the craft; (d) uncontrolled fall overboard; (e) injury to the diver and damage to the diving equipment during recovery onto the craft.
258. On the craft, before the descent of the diver, a warning signal indicating that diving work is being carried out shall be raised. The specific features of carrying out diving work from a small craft in the specific conditions of the production activity, taking into account the characteristics and capabilities of the craft used, shall be taken into account in the process flow chart for the performance of the work, the production planning documents and the instructions (guidelines, standards) developed by the organisation carrying out the diving work.
259. Training diving descents are carried out at specially equipped ranges from the shore or a pier, in swimming pools, in pressure chambers, at training complexes, from vessels (launches), or in compartments of a vessel specially equipped for these purposes.
260. Training diving descents are carried out in accordance with plans or programmes approved by the employer. The plans specify the place, depth, time and purpose of the diving descents, the diving equipment used and the means of supporting the descents; the safety measures specific to the current session are established; and the diving descent supervisors, standby divers, support personnel, and medical and logistical support are specified, as well as the procedure of actions in the event of an abnormal or emergency situation with a diver. When carrying out training diving descents, an action plan for the event of an abnormal or emergency situation shall be developed and put into effect. For the period of the training diving descents, a diving pressure chamber authorised for operation shall be kept in readiness for immediate use. During training diving descents to depths of more than 6 m, the pressure chamber shall be located in the immediate vicinity of the place of descents. In the absence of a pressure chamber or where it is not ready for use, it shall be prohibited to carry out training diving descents.
261. The section of the water area located within the water area of a natural body of water (sea, lake, reservoir, river) allocated for carrying out training descents shall be marked and fenced off. The bottom at the places of descent shall be cleared of objects presenting a hazard, and the water area shall be free of extraneous craft and floating objects. The results of the survey shall be documented in a statement, which the employer approves. The working (training) places at the section of the water area shall provide for the placement of a diving station and shall be equipped with stations holding diving equipment of various types, the necessary diving equipment, tools, ladders to the bottom, descent and running lines, and underwater structures simulating real objects and the conditions for carrying out diving work. The teaching and instructor personnel involved in carrying out training diving descents shall be trained in rendering first aid to divers who sustain injuries associated with the professional activity of divers.
262. When carrying out training descents at shore ranges and in swimming pools, not more than two trainees are lowered from a single ladder. At the place where training descents are carried out, there shall be a standby diver prepared for immediate descent, appointed from among the instructor staff (the organisation's full-time divers). In the case of advanced training and retraining, the standby diver may be appointed from among the divers being trained. Before the start of descents, the trainee prepares the diving equipment and carries out a working check only under the supervision of the instructor and makes a corresponding entry in the diving work log. When practising training tasks, divers' descents shall be carried out both using two-way voice (wired or wireless) communication and with a signal line. To enhance safety, a control line with a buoy may be used and (or) minor hydroacoustic means may be employed. In doing so, the descent and movement of the trainee diver shall be accompanied by a craft with a sufficient number of support personnel and with a standby diver in readiness for immediate submersion. Training descents in swimming sets of equipment in the autonomous configuration may be carried out in swimming pools. Descents in swimming sets of equipment in the autonomous configuration in a swimming pool and in water areas may be carried out paired with an in-water support diver-instructor who is in immediate direct contact with the trainee. While the trainee diver is under water, the diver-instructor shall carefully monitor his actions and behaviour, and, on loss of visual contact with the diver, shall enquire about his well-being every three to five minutes.
263. The specific features of carrying out training diving descents in the specific conditions of the educational activity shall be taken into account in the instructions (guidelines, standards) developed by the organisation carrying out the training diving descents.
264. Practice diving descents are carried out to maintain or restore the qualification skills and physiological fitness of the diving and medical staff, and also to master types of diving equipment new to the diver, not connected with its testing. Qualification diving descents are carried out to check abilities and skills when deciding questions of confirming (assigning) a qualification or of admitting divers to specific work. The planning of practice descents is carried out on the basis of the specific conditions of the organisation's production or service activity and shall ensure the maintenance of the qualification skills and physiological fitness of the diving and medical staff. It shall be prohibited to carry out working diving descents in equipment not mastered by the diver. Equipment is considered mastered by the diver where he passes a test before the organisation's commission for admission to training (practice) descents in the given type of equipment and performs in it a series of consecutive descents carrying out the entire set of actions for operating the given equipment, including switching to reserve methods of breathing and free ("emergency") ascent from shallow depths. The method of the diver's independent movement under water (by swimming, by walking on the bottom) is determined by the design of the equipment, the descent conditions, and the conditions of the organisation's production or service activity, and does not require special regulation by an admission order. When planning training and practice diving descents, divers' skills in both methods of movement under water in various types of equipment shall be developed. The initial gaining of depth in the water shall be performed consecutively at intervals of not more than 10 m; when repeatedly gaining previously reached depths, experienced divers may use an interval of 20 m. The gaining of depths in a "dry" pressure chamber may be carried out at intervals of not more than 20 m in the range of 40 - 100 m. A descent to 40 m in a "dry" pressure chamber may be carried out immediately, on the initial gaining of depths.
265. The arrangement for carrying out diving descents in the assessment of divers' qualifications shall comply with the requirements for carrying out training diving descents.
266. The specific features of carrying out practice and qualification diving descents in the specific conditions of production, service or other activity shall be taken into account in the production planning documents and the instructions (guidelines, standards) developed by the organisation carrying out the practice and qualification diving descents.
267. Diving descents for experimental (research) purposes and to master new diving hardware shall be carried out in accordance with programmes approved by the head of the organisation on whose premises these descents and work are carried out. The programmes are agreed by the scientific supervisor of the experiment and/or the head of the organisation developing the new technology, method, technique and other products subject to verification within the framework of the experiment (research). Before the start of experimental diving descents and work, a risk assessment shall be carried out, compensating actions shall be developed and labour protection instructions shall be drawn up, detailed down to each diving descent, upon a change of at least one working parameter which may lead to a change in risk and/or exert an influence or impact on the diver and other participants of the experiment (research). The action plan for the occurrence of abnormal and emergency situations shall provide for actions at all stages of the experiment (research).
268. Participants of experimental diving descents shall be in an employment relationship with the head of the organisation on whose premises the experiments (research) are carried out, for the period of the experimental (research) work. Participants of the descents shall confirm in writing that they have been familiarised with the conditions of the forthcoming work, its nature, the hazardous and harmful factors, the risks and the safety measures, and shall confirm their readiness to participate. Admission to experimental descents is granted by an order of the employer, on the basis of a record of a knowledge check under the programme and methodology of the experiment (research) by a commission which shall include the scientific supervisor of the experiment and the person in charge of the experimental diving descents.
269. The management of diving work during the conduct of experimental (research) diving descents is carried out by the person in charge of the experiment (research). Persons in charge of diving descents from among diving specialists having no less than 5 years of experience in supervising descents close in conditions and nature to the field of the experiment (research) may be admitted to supervise experimental diving descents. A pressure chamber ready for immediate use and admitted to operation shall be in the immediate vicinity of the descent site. A means for raising the diver in a vertical position in the event of an emergency situation shall be placed at the descent site. In the water area section, at the range or in the pool, the impact of possible surface and underwater sources of danger not related to the experiment (research) shall be fully eliminated, for which a report shall be drawn up and shall be approved by the employer. While the diver is under water, audio and video recording of the dives is provided and continuous monitoring of the diver's stay under water is established.
270. The specific features of carrying out experimental diving descents and work under the particular conditions of production, official or other activity shall be taken into account in the process charts, the production planning documents and in the instructions (guidelines, standards) developed by the organisation performing the experimental diving descents and work.
271. When planning diving work and at the initial risk assessment, normal and complicated conditions for carrying out diving descents are considered, which are determined from charts, sailing directions, the hydrometeorological characteristics of the work area, the documentation and information provided by the customer or the owner of the facility, and on the basis of experience of work at the facility (in the studied water area or at a similar facility), as well as from the results of an inspection of the facility at the work site. Carrying out diving work in difficult and special conditions requires more thorough preparation and the taking of measures to prevent the negative impact of additional hazardous and harmful production factors, as well as additional protection of the diver. Where it is impossible to eliminate or reduce the impact of hazardous and harmful production factors, the working time of divers shall be minimised by performing all possible preparatory operations at the surface, or the labour of divers shall be replaced by the use of technical means or unmanned underwater vehicles. The risks for carrying out diving work in special conditions shall be assessed in each specific case and on an individual basis. To eliminate or limit the impact of adverse, harmful or hazardous production factors and to protect the diver from their impact in special descent conditions, special decisions shall be taken, including the selection of diving equipment, diving hardware and equipment, the choice of descent methods and methods of performing the work, and the development of procedures for protecting the diver and for eliminating the possibility of unforeseen circumstances arising for predictable abnormal and emergency situations. The production planning documents or the permit to work shall specify under which particular conditions and/or circumstances the descents shall be suspended or prohibited.
272. Divers under water may not be directly subjected to the additional hazardous and harmful production factors classified as special conditions of diving descents, while these factors may exert an influence on other operations and stages connected with carrying out diving work and descents. Diving descents in special conditions may be carried out with the consent to the work of the person in charge of the diving descents and of the working divers, and shall be stopped on the first demand of the person in charge of the diving descents, of a diver or of another official, upon the detection or onset of dangers not taken into account before the start of the diving descents. The requirements for the competence (training) of divers for admission to work in special conditions are established by the employer.
273. The specific features of carrying out diving work in difficult and special conditions shall be taken into account in the instructions (guidelines, standards) developed by the organisation performing the diving work.
274. Before the start of diving work in a current, the hydrological regime at the work site shall be studied and the speed and direction of the current shall be determined at the surface and at various depths across the whole depth range, since the current at the sea surface may not coincide with the current at the bottom, in the water layers or at the work site. The current limits the working capabilities of the diver. The impact of currents on divers depends on the diver's work experience, his training in performing work in a current, the nature of the work and the method of dives.
275. Where tidal currents are present, the change of the current at different time periods shall be taken into account, and when carrying out diving work a schedule of high and low tides shall be available. Diving work in a current of more than 0.5 m/s is performed in diving equipment with a cable-hose bundle (CHB).
276. Diving work in a current of more than 1.0 m/s is performed in diving equipment with a cable-hose bundle and an emergency gas supply. If the design of the diving equipment does not provide for an emergency gas supply, additional means of protection and safeguarding of the diver and/or protective (guarding) devices and appliances shall be used. When preventing emergency situations at the facility (vessel) and saving people's lives, a dive in a current in the autonomous type of diving equipment may be carried out, provided that all reasonable safety measures are taken. A support craft shall be present when carrying out diving work in a current. Readiness No. 1 is established for the standby diver; the location of the standby diver is to be directly at the descent site of the working diver.
277. When carrying out diving work in a current, the additional hazardous and harmful production factors are: (a) change of the current, current fluctuations by depth and by time; (b) the impact of the current on the diver, his CHB, working lines and hoses, and process equipment used when carrying out diving work; (c) a reduction in the diver's working capacity owing to the energy expended in overcoming the force of the current; (d) movement over the bottom against the current; (e) drift of the vessel or loss of position by the vessel; (f) surfacing (blow-up) of the diver to the surface; (g) carrying away (tearing loose) of the diver or of the equipment for work by the current.
278. When carrying out diving work in a current, the following shall be prohibited: (a) carrying out diving descents in the autonomous type of diving equipment in a current of more than 1.0 m/s; (b) uncontrolled surfacing of the diver to the surface; (c) descents of divers while the vessel is under way, between the sides of vessels lying alongside each other, or between the side of a vessel and a quay; (d) fastening any lines (ropes) on the diver with a tightening loop.
279. When performing diving work in a current, actions shall be provided for to prevent the impact of hazardous and harmful production factors on divers, which may include: (a) carrying out training descents in a current; (b) planning descents for the period of time when the water current is directed away from the vessel; (c) the use of devices and appliances to protect the diver's work site; (d) reducing the degree of impact of the current on the diver, the diving hardware and the equipment for work; (e) the use of additional means of protection and/or safeguarding of the diver; (f) the use of working (descent, travelling, guiding) and other lines; (g) the use of weights, a weighted diving stage, weighted diving equipment; (h) reducing the working time of the diver under water in conditions of current impact; (i) planning simpler and/or shorter operations when the diver works in a current; (j) the use of means for marking and detecting the diver; (k) the use of launch-and-recovery devices for lowering the diver to the work site and raising him in an emergency situation; (l) the choice of a rational position for the vessel (support craft); (m) continuous monitoring of the reliability of the anchorage and/or holding of the vessel. The need to apply specific actions is determined from the results of the risk assessment depending on the conditions and nature of the diving work.
280. The time of effective work of the diver in a current depends on the following factors: (a) the diver's experience of working in a current and his training; (b) individual physical strength and endurance; (c) the type of diving equipment used; (d) the method and technique of lowering the diver under water; (e) the length of the paid-out cable-hose bundle, other working lines and hoses and their direction relative to the current; (f) the buoyancy of the cable-hose bundle, other working lines and hoses; (g) performing the work on the bottom or in the water column; (h) the nature of the work performed and the tools used to perform it; (i) whether the use of both hands is required to perform the task; (j) current fluctuations and changes in the direction of the current; (k) the possibility of assistance being provided by a second working diver if necessary.
281. When a diver descends in the open sea in current conditions, a diving stage shall be used. The diver's CHB shall allow for its fastening with carabiners at equal intervals to the descent line, the guide cables of the stage or a special cable with ballast to prevent it being carried away by the current.
282. The specific features of carrying out diving work in a current shall be taken into account in the instructions (guidelines, standards) developed by the organisation performing the diving work.
283. Exposure to sub-zero temperatures may lead to the overcooling of the diving station personnel and adversely affect the health, safety and effective work of divers or of the diving station personnel, as well as give rise to additional risks in the use of diving equipment and diving hardware. When working from ice, under ice and in sub-zero temperature conditions, the specific features of carrying them out shall be taken into account and appropriate actions shall be provided for to ensure the safety of the diving work.
284. For the descents of divers under ice, an ice-hole is made and cleared of ice. The dimensions of the ice-hole shall ensure the raising of the diver in the event of an abnormal or emergency situation in any spatial position, both with the support of a standby diver and without it. Along the edges of the ice-hole, decking is installed to prevent accidental slipping of the diving station personnel into the water, and a guard rail of the ice-hole not less than 1100 mm in height is installed. The ice-hole shall not have sharp edges; sharp and protruding parts shall be removed. A diving ladder or another device intended for lowering and raising the diver, which ensures the raising of the diver in the event of an abnormal or emergency situation involving the diver, shall be installed.
285. When preventing emergency situations at the facility (vessel), when carrying out rescue work, emergency rescue diving work and work to search for the bodies of the deceased, diving work may be carried out without arranging an ice-hole (descent into an ice polynya) in the swimming variant without installing a diving ladder. In this case, the CHB (cable-signal, signal line) on the side of the attendant diver is secured to the ice or to the shore in such a way as to prevent its paying out in the event of the attendant diver falling through the ice.
286. When determining the restrictions on the ambient air and water temperature, the following shall be taken into account: (a) the impact of additional factors such as wind, relative humidity, precipitation, ice formation, steaming at the water surface, warm currents. The risks caused by the impact of additional factors in sub-zero temperature conditions depend on the climatic zones and their specific features and are established on the basis of the risk assessment; (b) the restrictions on water and air temperatures established in the operating instructions for the diving equipment and diving hardware. For each increase in wind of 1 m/s, the restriction on the air temperature at which diving descents may be carried out shall be lowered by 1 °C. Descents in diving equipment without active heating means are carried out at air temperatures not below minus 20 °C, and where such means are used, down to minus 30 °C.
287. The employer provides the diving station personnel with personal protective equipment against the impact of sub-zero temperatures, taking into account the climatic belt at the location of the diving work. For the attendant on the cable-hose bundle, a procedure for changing mittens (gloves) and footwear is provided for, as well as arrangements for relief at the tending position. The conditions for the standby diver shall not lead to a reduction in readiness to descend to provide assistance in the event of an abnormal or emergency situation. When carrying out diving work lasting more than one shift at the diving work site in sub-zero air temperatures, a place shall be arranged for drying clothing, underwear, footwear and diving equipment and for their replacement in the course of the work.
288. Where it is necessary to carry out diving work in more difficult and/or extreme conditions in cases that do not permit delay, when carrying out rescue or emergency rescue work or work connected with preventing the occurrence of abnormal, emergency or extraordinary situations at the work facility, a risk assessment shall be carried out, actions to reduce them shall be developed, a rational and safest descent method and technique for performing the work (task) shall be chosen, and criteria under which the diving descents shall be terminated shall be established. In this case, diving work may be carried out only with the personal consent of the person in charge of the diving descents and of the working (descending) diver. Where it is necessary to carry out diving work in conditions of ice movement, specialised craft (self-propelled or non-self-propelled) equipped with a shaft for the descent of divers shall be used, which, depending on the descent conditions and the design features of the underwater part of the craft's hull, may be equipped with ice protection. Where it is necessary to carry out diving work from ice, an air-cushion vessel may be used.
289. When carrying out diving work from ice, under ice and in sub-zero outdoor air temperatures, the additional hazardous and harmful production factors are: (a) the low bearing capacity of the ice cover; (b) unexpected movements of the ice and detachment of the ice field; (c) the appearance of individual ice floes, wind-driven ice surge; (d) sudden discharges of water through a dam and other structures; (e) overcooling of the divers descending under water and of the diving station personnel; (f) icing-up of hoses, hose connections, reducers, the valves of the demand regulators of diving breathing apparatus, diving helmets, diving suits (wetsuits, diving dresses); (g) the formation of ice plugs in the hose connections; (h) injury against the ice edges and damage to the CHB by the ice edges; (i) disruptions in the supply of air (breathing gas mixture, BGM) for the diver's breathing; (j) the accumulation of condensate in the hoses and in the elements of the diving equipment and diving hardware, with subsequent icing-up, when moving from one temperature zone to another or when at the boundary of two zones.
290. When carrying out diving work from ice, under ice and in sub-zero outdoor air temperatures, the following shall be prohibited: (a) to lower a diver in the presence of moving broken ice; (b) to lower a diver from ice when cracks and water appear on the surface of the ice; (c) to lower into the ice-hole for the diver's descent the water hoses of pumps and other items not related to the diving equipment.
291. When carrying out diving work from ice, under ice and in sub-zero outdoor air temperatures, actions shall be provided for to prevent the impact of hazardous production factors on workers, which may include: (a) limiting the time divers stay under water; (b) the use of active heating means for divers and attending personnel; (c) the use of protective appliances to prevent damage to the head, the diving equipment, the diving hardware and the CHB; (d) the use of insulating underwear (thermal underwear, insulators, diving underwear) in a quantity ensuring the maintenance of the thermal balance of divers and attending personnel; (e) the marking of the sites of diving work and their fencing; (f) the confirmation by calculation of the time the diving station may remain in one place on the ice and of the permissible mass of the load during transport over the ice; (g) the measurement and monitoring of the ice thickness at the diving work site; (h) the installation of tents and heated cabins directly over the ice-holes or in the immediate vicinity of the descent site; (i) the use of heated breathing gas mixtures; (j) the rational placement of the diving hardware and the means of supporting the diving descents; (k) the distribution of duties among the diving station personnel with regard to preventing overcooling and a decline of attention during the diver's descent; (l) the availability at the descent site of hot water and heat-protective and heat-insulating materials for warming the diving hardware; (m) clearing the ice-hole (ice pit) of the ice cover, surface ice and broken ice; (n) the fitting of open-circuit breathing diving equipment with a main and a backup demand regulator, two reducers and the possibility of connecting them to a source of breathing gas mixture; (o) the establishment of continuous monitoring of the air supply to the diver, of the possible formation of plugs, of the position of the CHB relative to the edges of the ice-hole and of other hazardous factors. The need to apply specific actions is determined from the results of the risk assessment depending on the conditions and nature of the diving work.
292. Before each diving descent, the hoses shall be dried and blown through with compressed air. Before dressing the diver, the diving equipment shall be pre-warmed to an above-zero temperature, and the insulating underwear shall ensure comfortable thermal sensations for the diver when dressing. After putting on the diving equipment, the diver shall descend under water without delay, not allowing the elements of the breathing system to remain at the boundary of the water and air media. During work under water, the diver shall monitor changes and fluctuations in the air supply and in the breathing resistance on inhalation and exhalation. Changes in the operation of the diving equipment, the character of noise, the appearance of fluctuations in the air supply, an increase in breathing resistance on inhalation or exhalation shall be reported immediately to the person in charge of the diving descent. To avoid the formation of icing of the elements of the breathing system of the diving equipment after surfacing to the water surface, their emergence from the water shall not be allowed where possible. A repeat dive under water after surfacing and icing-up of the elements of the breathing system and of the safety valves shall be prohibited. The heavy parts of the equipment are removed from the diver who has come to the surface at the descent site, and the undressing of the diver shall be carried out in a warm room. Ice plugs in the hose connections are removed by heating the connections with hot water while maintaining the established air back-pressure in the hose. After each descent, the hoses, the elements of the breathing system and the safety valves shall be dried and blown through with compressed air. The specific features of carrying out the work when working from ice, under ice and in sub-zero outdoor air temperatures shall be taken into account in the instructions (guidelines, standards) developed by the organisation performing the diving work.
293. Diving work in conditions of radioactive contamination of the area (water area) and exposure to sources of ionising radiation (hereinafter - SIR) is carried out to save people and/or protect them from irradiation, to prevent the further spread of contamination, to search for, raise or conserve (localise) SIR during the elimination of an accident with a radiation factor, and to carry out repair and restoration work. When performing them, the established norms and sanitary rules for ensuring radiation safety shall be observed.
294. Divers who have passed certification for the right to conduct emergency rescue work to eliminate the consequences of radiation accidents, classified in the category of group "A" personnel and holding prior authorisation for planned increased irradiation in an effective dose of up to 200 mSv, may be admitted to diving work in conditions of radioactive contamination of the area (water area) and exposure to SIR. Before the start of work, a targeted briefing on radiation safety shall be conducted and the actual situation in the work area shall be communicated to all personnel. The person in charge of the diving work is subordinate to the person in charge of the emergency work or to the person in charge of the work to eliminate the consequences of a radiation accident (hereinafter - ELCRA). When carrying out work in SIR conditions, the duties of the person in charge of the diving work and of the person in charge of the diving descents may be combined. For carrying out diving work (descents) in conditions of exposure to SIR, a permit to work for this type of work is issued, which sets out the list of work, its regulations and the safety requirements.
295. The zone of the diving work is divided into a "dirty" zone and a "clean" zone. At the entrance to the "dirty" zone, a radiation monitoring post and a point for the sanitary treatment of personnel and the special treatment of diving equipment and of the means of supporting the diving work are organised. The actions to prepare for diving work, including the replenishment of air or BGM supplies, are carried out in the "clean" zone. The diving equipment used to perform diving descents in conditions of exposure to SIR shall be intended for this type of work, shall be sealed, shall ensure complete isolation of the diver from the environment, and shall be used in the hose variant with a supply of air or breathing gas mixture from a mobile cylinder group. Diving work in conditions of exposure to SIR shall be decompression-free. Where it is impossible to carry out diving work (descents) without decompression, the decompression shall be carried out using air for breathing on an extended regime. When carrying out diving work in conditions of exposure to SIR using BGM with an increased oxygen content, the doses of single irradiation shall be reduced by 25 per cent.
296. The working divers and the standby diver assigned to the descent place individual dosimeters on the chest and on the lower limbs before dressing in the equipment. The working divers and the standby diver are fully dressed in diving equipment in the "clean" zone, with the exception of the diving weights and diving boots; the helmet is put on and BGM is supplied for breathing. The diving station personnel are equipped with PPE for the skin and respiratory organs, as well as with means of individual dosimetric monitoring. Monitoring of the dose rate shall be carried out directly near the site of the diver's forthcoming work by means of remote submersible detection units, and monitoring of the dose rate shall be established during the period of the diver's performance of the work (task). When performing work under water, the diver shall protect his equipment from damage and from breach of its seal. In the event of a breach of the seal of the equipment, as well as when the established irradiation dose limit is exceeded, the diver is immediately raised to the surface. After the task is completed and the diver comes to the surface, partial special treatment of the diving equipment and partial undressing (diving weights, diving boots) of the working divers and of the standby diver (if he descended) are carried out immediately at the descent site, and all the diving station personnel proceed to the dosimetric monitoring post. On the basis of the results of the radioactive contamination monitoring, a decision is taken on the sanitary treatment of personnel, the special treatment of the diving equipment and of the means of supporting the diving descents.
297. When carrying out diving work in conditions of radioactive contamination of the area (water area) and exposure to SIR, the additional hazardous and harmful production factors are: (a) radiation injury to the personnel involved in the diving work; (b) breach of the seal of the diving equipment; (c) failure (loss of properties) of the inhalation and exhalation valves, of the diaphragms of the demand regulators and of other elements of the diving equipment; (d) contamination of the air or BGM supplied for the diver's breathing.
298. When carrying out diving work in conditions of radioactive contamination of the area (water area) and exposure to SIR, the following shall be prohibited: (a) the use of oxygen for breathing; (b) the use of wet-type diving suits and of diving equipment that does not provide complete sealing of the diver; (c) the replenishment of air supplies in the "dirty" zone.
299. When carrying out diving work in conditions of radioactive contamination of the area (water area) and exposure to SIR, actions shall be provided for to prevent the impact of hazardous and harmful production factors on workers, which may include: (a) monitoring of the radiation situation at the site of the diving work (descents); (b) the issue of medical radioprotective preparations according to the established regimen of administration; (c) the provision to the diving station personnel of the necessary PPE for the skin and respiratory organs; (d) the provision to the diving station personnel of means of individual dosimetric monitoring (individual dosimeters); (e) the use of equipment with double (duplicated) inhalation and exhalation valves; (f) the covering and sealing with polyethylene film of the diving hardware and of the means of supporting the diving descents to minimise radioactive contamination. The need to apply specific actions is determined from the results of the risk assessment depending on the conditions and nature of the diving work.
300. When carrying out the work, pre-developed standard process charts for the performance of the work are used. The procedure for performing the forthcoming work in the "dirty" zone shall be determined. The diving work shall be performed quickly, involving the minimum personnel necessary for the safe conduct of the diving descents. The working operations shall be provided with the necessary tools, appliances and measuring instruments. The specific features of carrying out the diving work shall be taken into account in the instructions (guidelines, standards) developed by the organisation performing the diving work.
301. The contaminated sections of the area and water area are cordoned off with barrier tape and radiation hazard signs. In the event that the permissible levels of radioactive contamination are exceeded, at the sites of the diving work (descents) and their approaches a set of protective actions is carried out to reduce the level of irradiation doses of personnel and/or actions to decontaminate these sites. The diving pressure chamber shall be located in the "clean" zone near the point of special and sanitary treatment. To minimise the time the diving station spends in the "dirty" zone, the delivery of personnel, of the means of supporting the diving descents and of tools from the radiation monitoring post to the sites of the diving work (descents) and back is carried out by a specially designated vehicle.
302. Before the start of diving descents in mountain conditions, divers shall undergo acclimatisation (adaptation) to the reduced partial pressure of oxygen (hypoxia) depending on the height above sea level, the divers' training to hypoxia and individual predisposition. The period of adaptation of divers is established when planning the work by a doctor (paramedic) in diving medicine. The admission of divers to diving descents is carried out by a doctor (paramedic) in diving medicine. A gradual ascent to the level of the dive altitude with rest periods at intermediate altitudes shall be carried out, and the diving work shall be commenced no earlier than 24 hours later.
303. For descents in mountain conditions, the tables of working decompression regimes of divers recommended by a doctor (paramedic) in diving medicine are used.
304. During the performance of diving work in mountain conditions, additional dangerous and harmful production factors are: (a) reduced atmospheric pressure; (b) individual predisposition to hypoxia; (c) steep and precipitous banks of rivers and lakes; (d) cold underwater currents, a sharp fall in temperature at night; (e) icing at the descent site and the formation of ice on the water surface; (f) the possibility of rockfalls, landslides, snow slides; (g) the presence of dry riverbeds along which water may suddenly flow; (h) the evaporation of harmful and dangerous gases near the water surface; (i) sunburn both from direct sunlight and from sunlight reflected off the water surface; (j) the expansion of gases as atmospheric pressure decreases.
305. During the conduct of diving work in mountain conditions, it shall be prohibited to admit divers to descents where there are no signs of acclimatisation and where there are complaints about the state of health. When developing the actions to be taken in the event of an abnormal or emergency situation with a diver, actions for transporting the casualty to a medical institution shall be developed, taking into account the following factors: (a) unstable communication or its absence; (b) the limited nature of transport communications; (c) the remoteness of medical institutions able to provide assistance in the event of an emergency situation with a diver.
306. During the performance of diving work in mountain conditions, actions shall be provided to prevent the impact on workers of dangerous and harmful production factors, which may include: (a) the provision of time for the acclimatisation of the personnel; (b) the planning of non-decompression dives; (c) the presence of a pressure chamber or a transportable pressure chamber in the immediate vicinity of the descent site; (d) the use of personal protective equipment against the sun and sunburn; (e) the features of the use of diving hardware and breathing gas mixtures. The need to apply specific actions is determined by the results of the risk assessment, depending on the conditions and nature of the diving work.
307. The features of the conduct of diving work in mountain conditions and/or high-altitude conditions shall be taken into account in the instructions (manuals, standards) developed by the organisation performing the diving work.
308. Water in inland waters and coastal zones may be contaminated by industrial, agricultural or domestic pollutants. The smell of the water, its colour, appearance and the location of factories or of discharges (outlets) of water from industrial facilities may indicate the presence of polluting substances. The selection of diving equipment shall be carried out on the basis of the need to ensure the water-tightness of the diver and to prevent direct contact of the exposed parts of the body with the water.
309. During descents into aggressive liquids and domestic sewage water, before each descent the diving suit shall be abundantly moistened with fresh water and a layer of liquid soap or of a surface-active substance shall be applied to its surface. The treatment and disinfection of the diving equipment are carried out before and after each descent. The duration of the diving descent shall be limited, and the descent method shall ensure constant control over the diver. At the diving station there shall be water, flushing and/or neutralising agents, disinfecting agents and wiping material. The use of diving suits (dive suits) and wet-type clothing for carrying out diving descents into aggressive liquids and domestic sewage water shall be prohibited.
310. During descents into silted water or the clay slurry of shafts, whose density is considerably higher than the density of water, an additional weight shall be hung on the working (descending) diver and weighted galoshes shall be put on. Descents in these conditions shall be performed in ventilated equipment with an emergency reserve of gas.
311. Work in narrow and confined conditions includes: work in the compartments of vessels, wells, tunnels, tanks, posterns, pipelines, inside pile foundations where the distance between piles, pipes is less than 1.5 m. It shall be prohibited for a diver to pass into openings of a diameter of less than 700 mm. During the performance of diving work in urban water-supply and sewerage systems, a sudden discharge of water is possible, or divers may fall into a zone of suction, increased flow or turbulence caused by the operation of water intakes and water outlets, as well as of other pressure, treatment, sewage systems or cooling systems. It shall be established from the owner of the facility whether there are any underwater obstacles or hazards in the immediate vicinity of the intended work site, and measures shall be taken to exclude the impact of the sources of danger, protective devices and appliances and other means of the physical protection of the diver shall be applied.
312. Descents in narrow and confined conditions and in restricted enclosed spaces are performed by analogy with descents into a compartment of a sunken vessel and are described in the corresponding Section of the Rules.
313. Diving descents during waves on the water surface have an impact on all stages of the diving work: the pre-launch stage, the immersion (descent) of the diver, the work of the diver, the ascent (exit) of the diver and the post-descent period. The safety issues arising during the performance of diving work in conditions of waves on the water surface shall be considered, including the method of descent and ascent of the diver, the work on deck of the supporting personnel, the reliability of holding the support vessel at the designated point near the diving work site, as well as the vertical movements of the vessel in the waves. The possibility of carrying out diving descents in conditions of waves on the water surface is determined by the results of the risk assessment. Diving work may be performed in conditions of sea waves of up to three points. In exceptional cases (during the conduct of rescue or emergency rescue work and the saving of human life), diving work may be performed during waves on the water surface in excess of three points, provided that the vessel is able to ensure reliable holding at the work site. During the conduct of diving work from specialised vessels (intended for carrying out diving work), the restrictions on waves on the water surface are established by the design and/or operational documentation for the vessel. Diving descents in conditions of waves on the water surface are carried out using a launch-and-recovery device and a diving stage or a diving bell.
314. During descents in the hours of darkness, the areas of preparation for diving descents, the control devices for the devices ensuring diving descents and work, and the water surface at the site of the divers' descent are illuminated. In the hours of darkness, the use of additional reference marks for the personnel of the diving station shall be obligatory. Indicator boards, marker buoys, transponder beacons, light and sound signalling devices, guide and running lines may be used as reference marks. The presence of a hand-held underwater torch with the diver in the hours of darkness shall be obligatory.
315. Limited visibility caused by fog, heavy precipitation, or vapour at the water surface leads to a reduction in the safety of diving descents owing to the loss of control over the situation, over the position of the diver on surfacing, over the position of the cable-hose bundle (CHB) and over other processes and parameters that have an impact on the timely taking of decisions. During the conduct of diving work in conditions of limited visibility, underwater technical means of viewing and observation shall be used, which are placed on the elements of the diving equipment and display to the person in charge of the diving descent the view in real time, or remotely operated underwater vehicles (hereinafter - ROV) shall be used to monitor the actions of the diver.
316. During the conduct of diving work involving descents into reservoirs with drinking water or into reservoirs with a reserve of water for domestic or fire-fighting needs, special safety measures and methods of performing the work shall be determined. Diving descents into reservoirs are carried out in the hose type of diving equipment with an open breathing circuit or in ventilated diving equipment with an emergency reserve of gas and a dry-type diving suit.
317. During the performance of diving work in closed reservoirs, additional dangerous and harmful production factors are: (a) structures in the immediate vicinity of flange joints; (b) the occurrence of an area with a pressure difference within the body of water of the reservoir owing to the emergency or uncontrolled starting of pumps; (c) a confined air space above the water surface in the reservoir, unfit for breathing; (d) limited possibilities for installing a diving ladder or stage for the descent and ascent of the diver. During the performance of diving work in closed reservoirs, units, pumps and other mechanisms shall be stopped and locked out, and warning signs are hung on the control panels.
318. During the performance of diving work in hot weather, additional dangerous production factors are: (a) the impact of high temperatures on the divers and the supporting personnel; (b) the direct impact of sunlight on the diving hardware, including cylinders and vessels operating under elevated pressure. Control over the condition of the standby diver, who is dressed in diving equipment and is in readiness for an immediate or emergency descent, shall be established. The loss of control over the condition of the standby diver leads to a reduction in his readiness to provide assistance to the working diver in the event of an abnormal or emergency situation.
319. During the performance of diving work in hot weather, actions shall be provided to prevent the impact on workers of dangerous and harmful production factors, which may include: (a) the installation of an awning (canopy); (b) the use of a sprinkling and air-conditioning system; (c) a change in the ventilation modes; (d) a change in the working modes of the divers and the supporting personnel; (e) the maintenance of the temperature inside the pressure chamber at a level comfortable for the diver; (f) taking into account the possible consequences of the expansion of gases and the loss of the properties of materials under the impact of high temperatures. The need to apply specific actions is determined by the results of the risk assessment, depending on the conditions and nature of the diving work.
320. When studying the area of the forthcoming work, the possible presence of dangerous representatives of the fauna, which may create a danger during the conduct of diving work, shall be taken into account. The person in charge of the diving work shall inform the divers about the possibility of representatives of the fauna inhabiting the area and shall develop additional measures for the protection of the divers. It shall be prohibited to send a diver down where there are bleeding wounds and abrasions on the exposed parts of the diver's body. During the performance of diving work in an area inhabited by dangerous representatives of the fauna, actions shall be provided to prevent the impact on workers of dangerous production factors, which may include: (a) the use of diving equipment painted in plain, non-bright colours; (b) the absence of shiny, bright, light-reflecting elements of the diving equipment used or of the diving hardware applied; (c) the use of physical means of protection, which include the diving refuge stage; (d) the use of passive means of protection, which include repellents, chain mail, reinforced diving suits; (e) the use of improvised means of protection, which include diving knives, poles, probes; (f) manoeuvring on a small craft in the area of the diver's descent with a standby diver ready to descend; (g) the assignment of additional supporting personnel to scare off marine predators. During the performance of diving work in an area possibly inhabited by dangerous representatives of the fauna or by large predatory marine creatures, all-round observation of the water surface in the inhabited areas shall be established. The need to apply specific actions is determined by the results of the risk assessment, depending on the conditions and nature of the diving work.
321. Diving descents in an area possibly inhabited by dangerous representatives of the fauna are carried out in pairs, where the second diver, providing support in the water, watches the situation around the working diver. Upon detecting dangerous marine animals, a back-to-back position shall be taken. During the period of work underwater, it shall be necessary to: (a) avoid contact with unfamiliar and dangerous representatives of the fauna and not provoke their attack; (b) move in the water calmly and smoothly, be attentive and cautious; (c) use improvised means of protection; (d) choose a dive profile, minimising, where possible, the angle of inspection for the diver. During the performance of diving work in an area inhabited by dangerous representatives of the fauna, additional dangerous production factors are: (a) the appearance of large or predatory marine creatures; (b) the hours of darkness and limited visibility; (c) descents in places where fishing nets are set; Diving descents in places where fishing nets are set and of commercial fishing, in areas of the discharge into the water of waste from fish-processing plants and food-processing enterprises present the greatest danger, associated with the appearance of dangerous representatives of the fauna, of large or predatory marine creatures.
322. Non-specific special conditions during the performance of diving work include electrical and magnetic storms, discharges of thunderstorm lightning, which may present a danger to personnel or equipment.
323. The features of the conduct of diving work in various conditions shall be taken into account in the technological charts, the production planning documents and the instructions (manuals, standards) developed by the organisation performing the diving work.
324. Shipboard diving work on vessels in operation and under repair may be performed both by the forces and means of the vessel and its crew, which includes a diving station, and by the diving stations of other vessels and/or of organisations having divers on their staff. When a vessel is berthed in a port, shipboard diving work for the inspection or repair of the underwater part of the vessel shall be performed only with the permission of the port administration. Before carrying out the work, clarification shall be made of the operation of the local regulatory acts in the port governing matters of labour protection and of the safety of the performance of diving work.
325. Shipboard diving work shall be performed only when there is confidence in the safety of the berthing or holding of the serviced vessel and/or of the vessel (craft) from which the diving work is carried out. Responsibility for the safe organisation of the conduct of shipboard diving work is borne by the master of the vessel, if the work is carried out from the serviced vessel. When work is carried out from a diving vessel (craft) or from the shore where the work is performed by a third-party organisation, responsibility for the safe organisation of the conduct of shipboard diving work is borne by the master of the diving vessel or the person in charge of the diving work of the organisation performing the diving work.
326. Before the commencement of the performance of shipboard diving work by the forces and means of a third-party diving station (organisation, vessel) carrying out diving descents and work, the person in charge of the diving work, on arrival at the serviced vessel, shall: (a) inform the master of the serviced vessel of readiness to carry out the diving work; (b) familiarise the master and the chief (senior) engineer of the serviced vessel with the safety measures during the performance of diving work, of which an entry shall be made by them in the permit to work for the performance of shipboard diving work; (c) organise constant two-way communication between all participants in the diving work on whom the safety of the diving work may depend; (d) agree with the master of the serviced vessel the procedure for performing the diving work (the plan, the programme) and the safety measures; (e) jointly with or in the presence of the master, carry out a briefing on the organisation of the conduct of the diving work with the personnel engaged for these purposes from among the crew of the serviced vessel; (f) make certain that on the vessel under-keel and marking lines (ladders, under-keel stages), plumb lines, where they are needed, are rigged, that warning signals are raised and that no loading and unloading work and no work involving the checking, starting and turning of mechanisms and devices which may affect the safety of the diving work is being carried out; (g) clarify with the master of the serviced vessel the possible hazards and carry out a risk assessment during the conduct of the diving work, determine compensating actions and agree the actions in the event of an abnormal or emergency situation with a diver. If diving work by the forces of a third-party organisation is carried out from a vessel (launch), make certain of the reliability and rationality of the berthing (mooring) of the vessel (launch) in relation to the serviced vessel, on the basis of considerations of safety and of the accessibility of the divers' descent site (the diving post) to the work site on the serviced vessel, and determine the procedure and organisation for re-mooring or hauling the vessel. In the event of a failure by the management of the serviced vessel to fulfil the necessary safety requirements, the performance of diving work shall be prohibited, of which an entry shall be made (documentarily recorded) and the master of the serviced vessel and the head of the organisation carrying out the diving work shall be informed.
327. The master of the serviced vessel (the head of the marine platform, of the drilling rig) is responsible for the actions of the vessel's crew affecting the safety of the diving work, for the timely informing of the organisation servicing the vessel about hazards and risks during work near the vessel (in the port, at the berthing place), for control over compliance with the plan (programme) of work and with the safety of its conduct, and performs the duties provided for by the Rules for the owner of the facility (the client) of the work, in addition to which he shall: (a) jointly with the chief (senior) engineer of the vessel, familiarise himself with the safety requirements during the conduct of diving work and inform the organisation performing the diving work of the possible hazards (a risk assessment on his part); (b) to ensure the safety of the diving work and to direct the actions for ensuring it, assign a responsible worker from among the command staff of the vessel, and where necessary assign for these purposes auxiliary personnel from among the crew of the vessel; (c) prohibit, during the conduct of diving work, the performance of work and actions which may affect the safety of the diving work, of which an entry shall be made in the ship's (watch) log; (d) ensure compliance with the requirements of safety and labour protection during the performance of shipboard diving work, sign the permit to work for the conduct of shipboard diving work and convey information about the conduct of the diving work to the entire crew, with an announcement over the ship's public address system of the commencement of work and with an entry about this in the ship's (watch) log; (e) on the yardarm of the side on which the diver will work, or in the most visible place, raise warning signals about the conduct of diving work; (f) when working in the hours of darkness or in limited visibility, ensure above-water lighting in the area of the conduct of diving work; (g) ensure the taking of depth soundings in the area of the diver's descent; (h) agree the procedure of actions in the event of an abnormal or emergency situation with a diver.
328. During the conduct of shipboard diving work, additional dangerous and harmful production factors are: (a) the actual depth to the bottom under the hull of the vessel; (b) unsafe berthing or holding of the serviced vessel and of the vessel from which the diving descents and work are carried out; (c) the switching on of the power supply of hydroacoustic instruments, of the active sacrificial-anode or cathodic protection of the vessel's hull; (d) accidental turning of the shaft lines, their drives, steerable nozzles, steering columns, the turning of the blades of a controllable-pitch propeller, of the rudder; (e) the opening of the bottom shut-off valves, the intake (outflow) of water from the intake openings, scuppers, the operation of the cooling systems; (f) a change in the position of the propeller and of the elements of the propulsion-and-steering complex; (g) a change in the heel and trim of the vessel, cargo or other simultaneous operations on the vessel, the intake or transfer of fuel; (h) the features of the contours of the underwater part of the vessel's hull; (i) the discharge of contaminated waters overboard the vessel, the leakage of fuel and lubricants, of dangerous cargoes, the ejection of rubbish and the falling of objects overboard; (j) confined conditions, limited visibility of the internal elements of the underwater part of the vessel; (k) a change in the position of the vessel's anchor chain.
329. During the conduct of shipboard diving work, it shall be prohibited to: (a) perform diving descents if the depth under the hull of the vessel is less than 2 m along the entire length, taking into account the amplitude of the vessel's oscillation in the waves; (b) carry out cargo operations, change the heel or trim of the vessel, take in or transfer fuel, switch on the power supply of hydroacoustic instruments, of the active sacrificial-anode or cathodic protection of the vessel's hull, turn the shaft lines, their drives, steerable nozzles, the rudder blade, open the bottom shut-off valves; (c) carry out diving work in a port without the notification and permission of the port administration; (d) perform work underwater near the intake openings or scupper openings in the underwater part of the hull until the intake (outflow) of water through them has ceased; (e) carry the under-keel lines, ladders, stages together with the diver or where the location of the diver is not established; (f) carry out the cleaning of the sea chests or gratings by hand; (g) allow a diver to pass between the blades of a propeller in a nozzle from one side to the other; (h) pass under the keel of the vessel from one side to the other without taking additional safety measures; (i) perform work between the hulls of vessels, the hull of the vessel and a quay, the hull of the vessel and supporting pontoons; (j) surface (come ashore) on the side opposite to the diver's descent site.
330. During the conduct of shipboard diving work, actions shall be provided to prevent the impact on workers of additional dangerous and harmful production factors, which may include: (a) taking into account the nature and features of the flow of the stream of water around the underwater part of the vessel's hull (of the floating object or structure) and the amplitude of the vessel's oscillation in the waves; (b) taking into account the contours of the vessel's hull, the location of the bilge keels, the roll stabilisers, the bottom and overboard valves and other protruding, lowering, rotating parts of the vessel; (c) control of the depth under the hull of the vessel; (d) the assignment of auxiliary personnel from the ship's complement of the serviced vessel; (e) the use of under-keel lines, stages, ladders, magnets, marking plumb lines; (f) the hanging out at the work site on separate lines of the tools and appliances for the work of the diver; (g) the hanging out of signalling and warning plates on the ship's posts and on the mechanisms whose operation (switching on, switching off) may lead to an abnormal or emergency situation; (h) measures to prevent the accidental turning of the mechanisms of the propulsion-and-steering complex and/or of its elements; (i) the lowering of a craft to support the work of the diver. The need to apply specific actions is determined by the results of the risk assessment, depending on the conditions and nature of the diving work.
331. Re-mooring of the vessel is carried out after the completion of the work and the raising of the diver on board the diving boat (craft). When two divers are working underwater at the same time and in the same area, the necessary safe distance shall be maintained between them.
332. During the inspection and repair of the ship's propulsion-and-steering complex and/or its elements and where there is a need to change the position of the propeller and of the elements of the propulsion-and-steering complex, the position shall be changed manually and only on the command of the working diver, transmitted through the person in charge of the diving descents.
333. The features of the conduct of shipboard diving work in various conditions shall be taken into account in the technological charts, the production planning documents and the instructions (manuals, standards) developed by the organisation performing the diving work.
334. For the performance of work in the internal spaces (compartments, holds) of a vessel in distress, two divers shall be sent down simultaneously. One diver performs the work; the other, the standby diver, holds the cable-hose bundle, observes his actions and shall, where necessary, provide him with assistance. During descents of divers into the internal spaces of a sunken vessel, the diving equipment shall provide for an underwater lamp, a means of video recording and a safety system for the diver for his raising.
335. Between the working diver and the standby diver, who are underwater, there shall be constant two-way voice communication. Doors and hatches shall be opened cautiously, since there may be a falling of poorly secured, overhanging or dislodged objects or loads and other heavy objects, as well as of jammed objects attempting to float up. Before entering a space, the diver shall take up onto his arm several turns of the cable-hose bundle (CHB) and, moving forward, gradually release them. Having opened a door or a hatch cover, the diver shall secure them against spontaneous closing (opening) with the aid of wire, a beam and other improvised means. The standby diver shall keep the CHB without slack and give slack only on the command of the working diver. In the event of the CHB catching, the diver shall reach the place of the catching, taking up onto his arm the slack of the CHB, and free it. After the freeing of the CHB, its slack shall be taken up to the surface on the command of the diver.
336. During the performance of diving work in the internal spaces of a vessel in distress, additional dangerous and harmful production factors are: (a) the threat of flooding, of a change in the trim and stability of the vessel, of the turning or capsizing of the vessel; (b) the swaying of the vessel under the influence of the waves; (c) the unstable or changing position of the distressed, sunken or grounded vessel; (d) the leakage of fuel and lubricants and of other aggressive liquids in the area of the descents; (e) the possibility of collapses, of the dislodging of ship's mechanisms, devices, doors, hatches and loads; (f) the sudden falling of poorly secured, overhanging or dislodged objects or loads; (g) sharp edges and burrs of the breach, of the edges of structures and constructions; (h) the possibility of receiving bruises from the spontaneous closing of doors, hatches, manholes; (i) the entanglement and jamming of the diver, the diving equipment and the cable-hose bundle (CHB); (j) confined places and restricted enclosed spaces; (k) insufficient illumination of the working zone; (l) entry into a zone of pressure differences and turbulence in the event of water leakage and the operation of dewatering means; (m) the presence of water leakage, entry into a stream of water or suction to breaches, damage and other places of water flow; (n) entry into a stream of water from the operating propulsors of the support vessel.
337. It shall be prohibited to carry out diving descents into the internal spaces without studying the actual situation, the location of objects, devices and structures. When working in the internal spaces, in confined conditions and in restricted and enclosed spaces, it shall be prohibited to move operating process equipment without switching it off. When a diver is in a partially flooded compartment or space (in a space with an air cushion), it shall be prohibited to remove the helmet (half-mask, band-mask), to open the helmet's viewport or to switch to breathing the gas composition of the air cushion. During diving work in the internal spaces, in confined conditions and in restricted and enclosed spaces, two divers shall be sent down simultaneously. One diver performs the work; the second (the supporting diver) holds the cable-hose bundle (CHB), observes the actions of the working diver, and where necessary provides assistance.
338. Emergency rescue diving work on a vessel in distress shall be prohibited if an assessment of the threat of flooding of the vessel, of a change in its trim and stability has not been carried out, if the degree of danger of the cargo of the vessel in distress to the divers has not been determined and if measures excluding the flooding of the vessel or its turning by wind or current have not been taken.
339. During the conduct of emergency rescue diving work, actions shall be provided to prevent the impact on workers of additional dangerous production factors, which may include: (a) the performance of preliminary calculations of the trim and stability of the vessel in distress afloat or of the conditions and case of grounding; (b) the taking of measures excluding the turning of the vessel in distress by wind, waves or current; (c) the turning and maintaining of the vessel in distress in such a position that the diving work is carried out on the leeward side; (d) the engagement of other vessels to shield the work sites from the waves; (e) the partial submerging of a vessel aground to prevent swaying and impacts against the bottom before inspection by the diver; (f) the securing of doors and hatches on the object in distress against spontaneous closing (opening), taking into account the existing heel or trim of the object; (g) the use of ladders, launch-and-recovery or anchor devices for descents into a flooded compartment; (h) the use of running, guide and other lines, as well as of lighting devices, when proceeding from the place of entry into the object in distress to the compartment with people; (i) the clearing of the passages into the internal spaces of the vessel in distress of collapses; (j) control over the work near the place of damage to the vessel's hull with the use of a video surveillance camera and/or cameras of the ROV; (k) familiarisation of the divers, by means of drawings and diagrams, with the location of the spaces and the equipment situated in them; (l) the choice of the route of movement of the diver, excluding going around various devices or objects by more than 180 degrees; (m) the use of a solid (rigid) diving helmet or of additional means of head protection when a full-face mask is used; (n) the installation of a strong source of light above the place of entry into the compartment for the orientation of the diver when exiting the flooded compartment; (o) the use of diving equipment with an underwater lamp, underwater two-way communication and means of video monitoring.
340. The removal of people from partially flooded compartments and spaces (from spaces with air cushions) shall be carried out by no fewer than two divers: one diver shall be located in the area of the entry into the object in distress and shall act as standby for the other, who is proceeding into the compartment for the people.
341. The additional factors for risk assessment during work to evacuate people from partially flooded compartments and spaces of capsized, flooded and distressed facilities are: (a) the volume of the air pocket; (b) the gas contamination of the space; (c) the number of people in the compartment; (d) the flooding depth of the vessel (the pressure in the air pocket); (e) the temperature of the water and air in the compartment; (f) the availability of food and drinking water; (g) the physical and mental state of the people; (h) the unexpectedness of discovering people in flooded compartments and, as a result, the emergence of elements of confusion among the divers; (i) the incorrect selection or adoption of erroneous principal decisions and methods for rescuing people from flooded compartments; (j) the time limit determined by the duration of people's stay in the compartment; (k) the lack of practical experience in carrying out such rescue operations.
342. A diver shall enter a compartment containing people with a lighting device and with the observance of caution, to avoid possible unexpected aggressive actions on their part, which may pose a threat to the diver's safety and impede the diver's performance of the assigned task.
343. The specific features of carrying out diving work, other than emergency rescue diving work, under various conditions shall be taken into account in the process flow charts, production planning documents and in the instructions (guidelines, standards) developed by the organisation carrying out the diving work. For carrying out emergency rescue diving work, standard process flow charts shall be developed within the organisation.
344. When carrying out diving work to place vessels on ship-lifting facilities (docks, slipways), the additional hazardous and harmful production factors are: (a) work in cramped conditions when inspecting the points of contact of the vessel's hull with the cribs and keel blocks when placing it in the dock; (b) the pressing of the diver or the diver's cable-hose bundle against the vessel's hull or the dock by disconnected and floating wooden parts of the launching devices; (c) the risk of injury when freeing the vessel's hull from the launching blocks.
345. When carrying out diving work to place vessels on ship-lifting facilities, actions shall be provided for to prevent the exposure of workers to additional hazardous and harmful production factors, which may include: (a) familiarising the divers with the arrangement of the keel blocks and with the locations and nature of damage to the vessel's hull; (b) the suspension, for the entire time the diver is underwater, of the work to place the vessel in the dock or to remove it therefrom. The list of necessary actions is determined on the basis of the specific conditions of the production activity.
346. When carrying out work to place vessels on ship-lifting facilities, it shall be prohibited: (a) to carry out diving descents when placing the vessel in the dock or removing it therefrom with the caisson gate's sluice valves open or during the pumping out (draining) of water, and also during the trimming or heeling of the vessel; (b) for the diver to pass from one side of the dock to the other beneath the keel of a vessel being placed in it or standing in it; (c) to carry out diving descents to clean the guard grilles of the dock's drainage system before the pumping out or intake of water has ceased; (d) to pass between the vessel's hull and the launching blocks, and also between their parts.
347. The specific features of carrying out diving work to place vessels on ship-lifting facilities shall be taken into account in the process flow charts, production planning documents and in the instructions (guidelines, standards) developed by the organisation carrying out the diving work.
348. Divers who have undergone vocational training corresponding to the type of professional activity and the nature of the forthcoming work, and who have passed a knowledge assessment on the safe methods and techniques for carrying out underwater engineering diving work, may be admitted to carry out work on the construction, repair and operational maintenance of hydraulic engineering structures. Before commencing underwater engineering diving work on the construction, repair and operational maintenance of hydraulic engineering structures, the diver shall, using the drawings and (or) the work execution design, familiarise himself with the arrangement of the structure, the conditions for carrying out the work, the safety measures and the labour protection requirements.
349. Diving descents when carrying out underwater engineering diving work (hereinafter referred to as UEW) shall be performed using the hose type of diving equipment. Underwater engineering diving work includes: (a) diving work on the construction, repair and operational maintenance of hydraulic engineering structures; (b) diving work in soil excavation; (c) diving work in operations with pipelines; (d) diving work in the laying and maintenance of electrical cables and communication cables; (e) diving work on the construction, maintenance and repair of hydraulic engineering structures at hazardous production facilities; (f) diving work in the performance of ship-lifting work.
350. When carrying out UEW, the availability of production planning documents and process flow charts and the completion of a permit to work for the work is mandatory. Matters of interaction between the administration of the facility's owner and the organisation carrying out the diving work shall be determined before the commencement of the work, and the actions of each of the parties in the event of abnormal or emergency situations involving the diver shall be determined.
351. When carrying out UEW, the additional hazardous and harmful production factors are: (a) the conduct of simultaneous and (or) joint operations involving various means and at various work sites when diving work is carried out; (b) damage to cables and pipelines and coming under their effect; (c) passage beneath anchor chains or alongside them; (d) a sudden release of water; (e) a current in the descent area exceeding 1.0 m/s; (f) the filtration of water and the creation of counter-current, turbulence and water pressure differential zones; (g) the lack of proper awareness on the part of the administration of the facility's owner and its duty dispatcher that diving work is being carried out at the facility; (h) the impossibility of stopping the water-pressure and water-intake structures for the period of the work; (i) the risk of suction against the grilles of the water-intake structures, of the diver or the diver's hands and the cable-hose bundle being drawn into the pipe; (j) coming under the effect of rotating mechanisms and operating units; (k) ignition or explosion during the repair of oil and gas pipelines; (l) electric shock during the repair of power cable lines; (m) the risk of damage to the diver, the equipment elements and the cable-hose bundle from fouling on the structures; (n) snagging on protruding underwater parts of the structures; (o) navigational hazards.
352. The greatest hazard during underwater engineering work at industrial facilities lies in the performance of diving descents at the work site within the zone of continuous operation of hazardous production facilities, ports, locks, navigation and waterway structures, hydroelectric power stations, dams and pumping stations and other facilities for industrial use, the suspension of whose operating regime is limited or impossible.
353. When carrying out underwater engineering diving work, it shall be prohibited: (a) to carry out underwater work within the protection zone of underwater power transmission cable lines that are energised and of pipelines under pressure; (b) to carry out work on the construction, operational maintenance or repair underwater in a port, in the zones of locks, hydroelectric power stations, pumping stations, dams and other structures without obtaining the corresponding permission of the authorised representative of the facility (the power dispatcher, the traffic dispatcher, the duty dispatcher); (c) to release water and create a current exceeding 1.0 m/s in the diving descent area when carrying out work under the operating conditions of the structures (at navigation structures during the navigation period); (d) to carry out descents of divers to unstable elements of hydraulic engineering structures and constructions; (e) to drive piles, raise or lower loads, move watercraft and carry out other work in the vicinity of the diver's work site (the safe zone is determined by the person in charge of the diving descents taking into account all possible hazardous factors); (f) to inspect a hydraulic engineering structure without mittens, to insert hands or feet into the gaps between the constructions of the structure to determine the clearances between them; (g) to lower divers where there is no information on the underwater sources of hazard.
354. When carrying out UEW, actions shall be provided for to prevent the exposure of workers to additional harmful production factors, which include: (a) the development of process flow charts before the commencement of the work; (b) obtaining the route plan of the alignment of the cables and pipelines located within the work area; (c) familiarising the divers, using the drawings, schemes, work plans (designs) and process flow charts, with the arrangement of the structure, the existing sources of hazards, the conditions and procedure for carrying out the work, and the safety measures; (d) obtaining information on the presence or absence of electrical power cables, telephone cables or pipelines at the work site; (e) securing the moving elements of the structure against driving winds and spontaneous closure (opening); (f) determining the locations of water filtration and the positions of other sources of hazards underwater without lowering divers; (g) establishing, before the commencement of the descents, safe distances from the diver's work site to the underwater sources of hazards; (h) reducing the speed of the water current to acceptable norms (it is recommended not more than 1.0 m/s); (i) ceasing the intake of water at the water-pressure and water-intake stations; (j) changing the operating regime of hydraulic engineering structures for the period during which the diving descents are carried out; (k) installing additional protection on the suction and water-outlet devices. The need to apply specific actions is determined based on the results of the risk assessment, depending on the conditions and nature of the diving work.
355. The excavation of pits, trenches, the washing away of soil and other work involving disturbance of the surface layer of soil may be carried out after the person in charge of the diving work has obtained information on the absence of electrical power cables, telephone cables or pipelines at the work site. The protection zone of underwater power transmission cable lines that are energised and of pipelines under pressure is determined as a section of water space from the water surface to the bottom, enclosed between vertical planes situated at a distance of 50-100 m from the outermost cables or the pipeline on each side, depending on the width of the water obstacle. The boundaries of the hazardous and protection zones are determined by sectoral regulatory acts, are specified by the facility's owner and shall be issued to the organisation carrying out the diving work before the commencement of the diving work. During the work, the diver shall ensure that his hand and (or) cable-hose bundle are not drawn into the pipe. Without ceasing the intake of water, the diver may work if the intake pipe is equipped with a protective grille and additional measures have been taken to prevent suction of the diver and the drawing in of elements of the diving equipment or the cable-hose bundle.
356. The labour productivity of divers increases when underwater constructions are assembled from units and blocks. The possibility of using units and blocks in the assembly of structures and constructions shall be taken into account both at the design stage and in the process of organising the work. The low productivity of the manual labour of divers shall be replaced by the use of means and methods of mechanising the production processes, by the introduction of new techniques and technologies of the labour of divers and (or) of production. Those preparatory operations which cannot be performed by workers on the surface shall be assigned to the divers. The diver shall fit the units and blocks in place at the installation location. Where additional processing of the elements of the constructions is required, they shall be raised to the surface, where they are processed by workers according to the marks made by the diver. The labour productivity of divers and his safety during the performance of the work are affected by the volume and quality of the preparatory operations on the surface and the degree of equipping of his work site underwater.
357. The commencement of diving work in the area of the location and operation of soil excavation means is permitted after the coordination of actions between the person in charge of the diving work and the person in charge of the work with the soil excavation means. When excavating soil in pits and when cutting deep trenches, their walls shall be made gently sloping (within the angle of the natural slope of the soil). When excavating alluvial soil inside water-pumping stations, where it is not possible to observe the angles of the natural slope, the soil shall be excavated layer by layer. When flushing a tunnel with soil-washing means, in the case of the simultaneous work of two or more divers, the recommended safe distance between them shall be not less than 10 m, except in the case where one of them is working with a soil-suction device and the second diver is loosening the soil in front of him with a non-reactive nozzle. The actions of the divers shall be continuously coordinated. Descents when carrying out soil excavation work shall be performed in diving equipment with a cable-hose bundle in the configuration with a rigid helmet.
358. When excavating soil, the additional hazardous and harmful production factors are: (a) the lack of coordination of the actions of the personnel; (b) the work of two or more divers in a pit (trench) simultaneously; (c) the direction of the jet of the hydraulic nozzle and the direction of the discharge of the slurry; (d) the diver releasing from his hands a soil-washing device that is under pressure; (e) the ejection of the diver or the pneumatic soil-suction device to the surface; (f) the entanglement of the cable-hose bundle with the hoses of the soil excavation means; (g) the collapse (burial) of the diver in a trench and pit; (h) the manual excavation of rock soil by divers using load-lifting mechanisms; (i) the tearing off of the full-face mask or band mask during a collapse, entanglement, ejection or coming under the effect of the jet; (j) the increase in the working depths of the divers when excavating soil; (k) other dredging work in the area where diving descents are carried out; (l) the starting-up of the soil excavation means while the diver is underwater without the permission (command) of the diver.
359. When carrying out soil excavation work, it shall be prohibited: (a) to carry out diving soil excavation work without two-way voice communication with the diver; (b) to release from the hands a hydraulic nozzle that is under pressure; (c) for the diver to inspect the location being washed on the soil without relieving the pressure of the working medium on the soil excavation means; (d) to clean by hand the intake openings of various soil-washing devices; (e) to clean the intake openings of various soil-washing devices without relieving the pressure of the working medium; (f) to descend into a trench and pit without having ascertained that the slopes of the trench or pit have formed and do not threaten to collapse; (g) to carry out diving descents during the operation of scrapers, dredgers, excavators, grabs; (h) to lower and raise the diver using the working element of the soil excavation means.
360. When carrying out diving soil excavation work, actions shall be provided for to prevent the exposure of workers to additional harmful production factors, which may include: (a) taking into account the type of soils and their properties; (b) securing to an anchor, ballast, load or protruding parts of the structure the soil-washing device that generates a reactive force, its pressure hose and (or) discharge hose; (c) the removal or washing-out of the soil accumulating behind the diver when working in tunnels; (d) establishing control over the laying of the slopes, their steepness, the bottom elevations and the dimensions of the pit, taking into account the safe conditions for carrying out the diving work and the physico-mechanical properties of the soils; (e) preparing for action the means for eliminating a possible burial of the diver (including soil-suction devices, ejectors, fire nozzles with hoses connected to the water fire-extinguishing system of the support vessel, floating crane); (f) installing video monitoring of the working divers by means of helmet-mounted video cameras or a remotely operated underwater vehicle (ROV); (g) arranging the recording of the actual depth on each descent of the diver; (h) assigning additional support personnel to monitor the hoses of the soil excavation means and to supply (shut off) the working medium. The need to apply specific actions is determined based on the results of the risk assessment, depending on the conditions and nature of the diving work.
361. Labour protection requirements for carrying out diving work on the laying, maintenance and repair of pipelines in marine conditions and in the conditions of inland waterways and water bodies shall be contained in the labour protection instructions and the standards for the safe activities of organisations, as applicable to the specific conditions of production. Before the commencement of the diving work, the person in charge of the diving work and the person in charge at the site of the work on the laying (maintenance, repair) of the pipeline shall coordinate the deployment of forces and means in the area where the work is carried out and shall determine the organisation of interaction.
362. When carrying out diving work with pipelines, the additional hazardous and harmful production factors are: (a) the conduct of joint or simultaneous operations involving various means and at various work sites; (b) the falling (breaking away) of sections, pipes, mats, pallets and other means for the repair of pipelines that are lowered underwater; (c) coming into the zone of pressure differentials or depressurisation of the pipeline; (d) faults in the ballasting, slinging or negative buoyancy of the pipelines, pontoons and other means that are lowered underwater; (e) damage and injury during the dismantling of the ballasting, lining, insulation coatings; (f) the depressurisation of the underwater sealing chamber.
363. When carrying out diving work with pipelines, it shall be prohibited: (a) the use for lowering and raising divers of load-bearing ties and devices supporting the pipeline; (b) carrying out a diving inspection of the pipeline or the unloading pontoons before the completion of the cargo operation; (c) checking the alignment of the openings of the fixed and rotating flanges and determining (measuring) the clearances between the pipes being joined by means of the hands; (d) carrying out gauging and measurements by means of the hands and the elements of the diving equipment; (e) carrying out diving descents during the hydraulic or pneumatic testing of the pipelines; (f) being in the vicinity of the cutting cable and in the direction of the application of forces during the dismantling of the pipeline.
364. When carrying out diving work with pipelines, actions shall be provided for to prevent the exposure of workers to additional harmful production factors, which may include: (a) obtaining the route plan of the alignment of the pipelines located within the work area; (b) checking the reliability of the slinging of the sections, pipes, pallets, mats and other means and materials lowered underwater; (c) determining safe locations and working zones for the divers, the installation of means for the orientation of the diver underwater; (d) the use of a cable locator, a remotely operated underwater vehicle and other technical means of search and survey; (e) the use of a tool or special devices when carrying out gauging and measurements; (f) relieving the pressure from the pipeline before the diving work. The need to apply specific actions is determined based on the results of the risk assessment, depending on the conditions and nature of the diving work.
365. The lowering of a diver while a pipe-laying barge is moving shall be prohibited. Where circumstances and production conditions arise in which it is necessary to lower a diver, when assessing the risks the distance to the working element and the directions of the wind and current shall be taken into account, specific safety measures shall be developed and additional means of protection for the diver shall be used.
366. Before the commencement of the work on the laying and maintenance of electrical cables and communication cables, the person in charge of the diving work shall obtain from the facility's (cable's) owner the route plan of the alignment of the cable lines in the area where the diving descents are carried out, the boundaries of the hazardous and protection zones, and shall coordinate the actions between himself and the diver in the event of an emergency situation.
367. When carrying out diving work on the laying and maintenance of electrical cables and communication cables, the additional hazardous and harmful production factors are: (a) damage to the cables and coming under their effect; (b) the laying of the cable and the operation of the cable-laying machine or its working element; (c) the accidental application of voltage to the cable being laid, inspected or repaired; (d) the pulling of the cable through the protective pipes of the shore well; (e) coming under the sledge or hydraulic plough of the cable layer; (f) the drawing of the diver's hand or the diver's cable-hose bundle into the protective pipe; (g) damage to the insulation of the cables; (h) the increase in the working depths of the divers when excavating soil for the laying of the cable.
368. When carrying out work on the laying and maintenance of electrical cables and communication cables, it shall be prohibited: (a) to lower a diver and to be underwater during the laying of the cable and during the operation of the cable-laying machine or its working element; (b) to use metal probes and other sharp objects to detect electrical power cables.
369. When carrying out diving work on the laying and maintenance of electrical cables and communication cables, actions shall be provided for to prevent the exposure of workers to additional harmful production factors, which may include: (a) obtaining the route plan of the alignment of the cables located within the work area; (b) familiarising the personnel with the work execution design and the process flow charts; (c) cleaning the working elements only after the removal of voltage and pressure in the working elements of the underwater cable layers; (d) precluding the possibility of the accidental application of voltage during the laying, inspection or repair work performed by divers on the cable. The need to apply specific actions is determined based on the results of the risk assessment, depending on the conditions and nature of the diving work.
370. When carrying out diving work at hazardous production facilities, the requirements of the Federal Norms and Rules in the field of industrial safety shall be complied with.
371. When carrying out diving work on the construction, maintenance and repair of hydraulic engineering structures at hazardous production facilities, the additional hazardous and harmful production factors are: (a) a change in the operating regime of the facility (lock, dykes, dams, spillways, water drains, reservoirs, docks, inlet collectors); (b) the lack of proper awareness on the part of the administration and operating personnel of the facility that diving work is being carried out; (c) the lack of proper awareness on the part of the organisation carrying out the diving work of the sources of hazards at the facility, both in the above-water and in the underwater part; (d) the occurrence of abnormal or emergency situations at the work facility that are not connected with the performance of the diving work; (e) injury against protruding parts of the structures, against elements of the structures that are in a state or position differing from the working (normal, design) one, as a result of deformation, destruction, breakage and other types of failure; (f) loading and unloading work, load-lifting operations and other operations for the submersion of constructions, devices, structures underwater and their installation underwater; (g) the breaking away of a load, constructions, objects, elements or structures during their raising and (or) submersion underwater; (h) a sudden jerk when raising (tearing away) heavy and large-sized constructions from the soil; (i) the discrepancy of the actual depth of the descent (of the work) with the design one; (j) the pressing, entanglement or snagging of the diver and (or) the diver's cable-hose bundle during the installation of constructions underwater into the design position under the observation of the diver; (k) the dumping and adding of stone and other materials underwater; (l) the increase in the working depths of the divers at particular stages of the construction work associated with the technologies and technological processes applied; (m) filtration at the points of junction of the underwater part of the structure with the natural bottom; (n) the filtration of water at the points of damage to the water-pressure and hydraulic engineering structures; (o) the discovery of explosive objects underwater and the performance of underwater blasting work; (p) direct contact of the diver or the diver's cable-hose bundle with the water filtration point, the working element of the vibration-compaction unit, the guides, frames and other devices underwater.
372. When carrying out work on the construction, maintenance and repair of hydraulic engineering structures at hazardous production facilities, it shall be prohibited: (a) to throw rubbish and objects into the water during the performance of the diving work; (b) to go around trestle-type obstacles by more than 180 degrees; (c) to carry out diving work at facilities without the use of hand protection means (gloves, mittens); (d) to carry out diving descents at the location of load-lifting operations and during the submersion of constructions, structures, technological devices, materials underwater, from their beginning to their completion; (e) when carrying out diving work, to use slings, chains, spreader beams and other load-gripping devices and appliances that have not passed inspection, with expired inspection periods or that do not correspond in terms of permissible load to the design weight of the load, and also with signs of rejection; (f) when carrying out diving work, to use load-lifting mechanisms and devices with expired examination periods; (g) to carry out the dumping (adding) of stone without guiding devices (chutes, pipes) and without warning the person in charge of the diving descents and the diver of the beginning of the operation; (h) the performance of diving work during pile driving, vibration-compaction work, the movement of watercraft; (i) to insert hands, feet or elements of equipment into the gaps between the constructions of the structures to measure or determine the clearances between them, to determine the location and magnitude of the water filtration; (j) the performance of diving work without a protective cradle, special guards and appliances protecting the diver from suction at the points of water filtration; (k) to enter head first into a pipeline with a diameter of less than 1 m; (l) to perform work that may create a threat to the safety of divers when working underwater.
373. When carrying out diving work for the construction, maintenance and repair of hydraulic structures at hazardous production facilities, actions shall be provided for to prevent the exposure of workers to additional harmful production factors, which may include: (a) confirmation that the facility administration, the manager at the work site, the duty dispatcher and the operational personnel have been notified of the diving work being carried out at the facility and know the place where it is carried out; (b) agreement with the responsible representative of the customer (owner of the facility) on the safety measures and the actions in the event of an abnormal or emergency situation; (c) establishment of stable two-way communication with the responsible representative of the customer (owner of the facility) and (or) its duty dispatcher; (d) forming the composition of the diving station in a number that ensures the safe performance of diving work under the specific conditions of the operation; (e) selection of a rational route for the diver's movement underwater that minimises the possibility of entanglement, snagging and injury; (f) establishment of continuous monitoring of the position of the working diver and the actual depth of descent; (g) establishment of safe distances when the diver is underwater where it is necessary to observe construction and installation operations; (h) use of lighting equipment underwater and on the surface in conditions of limited visibility and during the hours of darkness; (i) use of video surveillance systems using helmet-mounted video cameras or remotely operated uncrewed underwater vehicles during the diver's work underwater; (j) use of protective devices, barrier fittings and other means of protecting the diver when performing construction and installation work in a current, in the area of spillways, at places of water flow or seepage; (k) use of protective barriers, restraint and fall-arrest systems, and also positioning systems to exclude possible direct contact of the diver at points of damage, with working elements, moving or rotating mechanisms; (l) use of diving ladders and launch and recovery devices when carrying out diving work from structures and constructions; (m) use of the necessary floating craft where it is not possible to carry out work from structures and constructions; (n) use of means of work mechanisation; (o) use of load-lifting and load-gripping means, devices and fittings that have passed periodic inspection (testing) and whose characteristics correspond to the design loads; (p) use of diving equipment, means of supporting diving descents, and equipment and devices for performing diving work that have undergone periodic maintenance and repair; (q) installation of buoys, marker poles, markers and other means of marking in the area where diving work is carried out; (r) use of tools or special fittings for measurements; (s) posting, in the room with the control units, of a representative of the organisation carrying out the diving work for prompt response to the actions of the hydraulic structure personnel or in the event of an abnormal or emergency situation; (t) replacement of divers' labour with the use of remotely operated uncrewed underwater vehicles and other technical means of underwater observation when carrying out operations to submerge and lift structures, to install them in the design position, and when performing other most hazardous operations. The need to apply specific actions is determined by the results of a risk assessment depending on the conditions and nature of the diving work. During diving work with open sluice gates, warning signs shall be placed at a distance both upstream and downstream, and where necessary the passage of vessels near the area of the diving work shall be prevented. When carrying out diving work on hydraulic structures, the support personnel shall be protected from falling into the water and shall wear life jackets or work-and-safety vests. The place and method of the divers' descent shall be selected so that the place of the diver's direct work (the working zone) is within the field of view and ensures monitoring of the position of the working diver by the person in charge of the diving descent or by the support diver. The diver's lines shall not cross hazardous zones (the seepage zone or the pressure-differential zone), projecting structures, sharp edges, corners and other obstacles posing a threat of injury, damage, entanglement or snagging.
374. The inspection of foundations, supports and hydraulic structures at a depth at the place of descent of more than 12 m shall be started by the diver from the lower section, rising as the structure is inspected and serviced and without thereby breaching the decompression regime. When determining the boundaries of hazardous zones and safe distances, the following factors shall be additionally taken into account: (a) the operating radius of the crane jib, taking into account the dimensions of the load; (b) the effect of natural conditions (wind, waves, current, visibility at the water surface) that may lead to a change in the position of the mechanisation means and (or) displacement of the load (structures); (c) the effect of natural conditions (visibility underwater, current, depth of descent) that may lead to loss of orientation by the diver during work; (d) the effect of surface and underwater sources of danger in the area where the work is carried out and at the place of the divers' descent; (e) the need for decompression of the diver; (f) the placement of the place of the diver's descent, the direction of his cable-and-hose bundle and the placement of the means for lifting the diver in the event of an abnormal or emergency situation.
375. When submerging structures, constructions, technological devices and materials underwater, diving descents are suspended, and the diver exits the water or takes up a position at the established safe distance. During lifting, a position may be considered safe when the load has fully emerged from the water and is placed on the cargo platform or moved away to a safe distance from the place where the diving descents are carried out and its breaking loose cannot affect the safety of the diving work. When submerging underwater, a position may be considered safe when: (a) the lower part of the structure fully rests on the bottom (at a level below the installed structure) or is suspended above its installation point at a distance at which no threat to the diver's safety arises; (b) the working element of the vibration unit is lowered onto the bed; (c) the metal frame, guide devices or other fittings are fully lowered underwater and lie on the bottom (bed).
376. When carrying out diving work on the water-conveyance structures and devices of operating hydraulic developments, the following actions shall be carried out to ensure the safety of divers: (a) the owner of the facility and (or) the head of the managing organisation shall be notified in writing of the dates for performing the diving work at the facility, and on the day the diving work begins the duty dispatch service of the facility and the operational personnel of the facility shall be notified; (b) a permit to work for carrying out the diving work shall be signed, and the work plan (programme) shall be communicated to the duty dispatch service of the facility and the operational personnel of the facility; (c) before the diving descents begin, the readiness of the facility for the diving work shall be confirmed, continuous two-way communication shall be established and permission to begin the diving work shall be obtained; (d) warning signs shall be installed at the entrances to the equipment rooms, unit rooms and switchgear rooms; in individual cases, where necessary, lock-out access blocking is used; (e) such a number of units or gates shall be stopped or closed that, within a radius of not less than 50 m from the place of the diver's work, the water flow velocity does not exceed 0.5 m/s; (f) the guide vanes and starting devices for turbine regulation shall be closed; (g) the openings and working zones shall be sealed using improvised materials, patches, cribs and caissons, or the flows shall be diverted using deflectors; (h) a visual check shall be carried out for the absence of swirls on the water surface at the place of descent and above the place of the intended work; (i) the mechanisms for starting the units, raising the gates and opening the gates shall be switched off (de-energised, the hydraulic devices switched off); warning signs shall be hung on the switching-off devices. Diving work on the underwater part at the water-conveyance structures and devices of operating hydraulic developments shall be carried out on the basis of a technical assignment developed by the organisation operating the structure, in accordance with the diving work plan or the inspection programme. Where it is impossible to change the operating regime of the facility to create normal conditions for performing the diving work, it is preferable to carry out the work underwater using remotely operated underwater vehicles and (or) joint work of the diver and the ROV with a limitation on the diver's working time. For instrumental or instrument-based inspection, quantitative measurements or sampling, technical means and devices that create additional dangers for divers may be used. In this case, the requirements for safe operation shall be contained in the labour protection instructions.
377. When carrying out diving work on underwater concreting (installation of reinforcement, embedded parts and formwork, concrete pouring, dismantling of formwork and other work performed underwater), the additional dangerous and harmful production factors are: (a) the risk of injury to divers due to the temporary unstable state of the structure, the facility, the formwork and the supporting fastenings; (b) the presence of chemical additives in the concrete mix and the possibility of chemical burns to the skin and damage to the workers' diving gear; (c) the injury hazard of reinforcement-tensioning work; (d) the effect of noise and vibration and the possibility of electric-shock injuries when using electric vibrators and electric heating of concrete; (e) the injury hazard of work when using mechanical, hydraulic, pneumatic and other tools.
378. Divers who have undergone verification of knowledge of the safe methods and techniques for performing underwater concreting work may be admitted to diving work on underwater concreting. The actions for preventing the exposure of divers to dangerous and harmful production factors when carrying out concrete work underwater shall be included in the production planning documents, the process charts and the permits to work. The specific features of carrying out diving work when performing underwater concreting work shall be taken into account in the process charts, the production planning documents and the instructions (guides, standards) developed by the organisation performing the diving work.
379. Diving descents and work may be carried out jointly with an ROV or under the control of an ROV (hereinafter - diving descents jointly with an ROV). When performing diving work, an ROV may be used for inspection and determination of the diver's place of work, for ensuring the diver's movement to the place of work, for observing the situation in the zone of the underwater work and assessing potential dangers to the diver, for ensuring observation of the diver's movement in conditions of limited visibility, for delivering diving tools to the place where the work is carried out, for monitoring the safety of the diver's work, for observing the progress of the work performed by the diver, for controlling his actions and for providing prompt information to the person in charge of the diving descent.
380. Where joint work of a diver with remotely operated underwater vehicles is required, labour protection instructions shall be developed, taking into account the design differences of the ROVs and the methods of their use. To ensure interaction between the diving station and the ROV crew, a table of command words (standard commands) is drawn up, containing the necessary and sufficient minimum of information ensuring the safety of the diver. The table of commands shall be communicated in advance to all workers and posted at all command points (stations). During the risk assessment, the assessment team shall include the ROV operator (pilot) and (or) the person in charge of the ROV descents.
381. Before the start of a diving descent jointly with an ROV, the personnel involved shall be briefed on the sequence of performing the operation, the interaction algorithm when performing the specific work (task) and the necessary measures to ensure safety, including the possible risks and operational limitations when working with the ROV.
382. The briefing before the start of the work shall be attended by the personnel of the diving station involved in the forthcoming work and the personnel servicing the ROV.
383. When working with divers, the boundaries of the ROV's area of work shall be determined (the working zones, the functions of the ROV and other information affecting the safety of the forthcoming work). The personnel performing direct work with the ROV shall be trained and certified in electrical safety at not lower than electrical safety group II. When using an ROV to support divers, the ROV operators (pilots) shall have sufficient experience in operations connected with supporting the divers' work. Less experienced operators (pilots) shall be supervised by a mentor with sufficient experience of supporting divers' work or by the person in charge of the ROV descent.
384. When planning joint work of divers and the ROV and developing process charts, the sudden emergence of a need to descend a standby diver or a second working diver while the ROV is in the water shall be taken into account. When making changes to the technology and (or) method of performing the work that affect changes in the safe distances between the ROV and the diver or in the working zones, the working diver shall be replaced, and the next diver to descend is set new tasks and given new limitations at a repeat briefing.
385. Direct duplex voice communication is provided between the person in charge of the diving descent and the person in charge of the ROV descent. Telephone duplex voice communication is provided between the person in charge of the diving descent and the diver working with ROV support. Each diver working with ROV support shall have, as part of the gear, a helmet-mounted video camera and a helmet-mounted light. The video image from the main video camera (cameras) of the ROV and from the diver's helmet-mounted video camera is transmitted continuously in real time to the video monitors located at the workstation of the person in charge of the diving descent. With the use of the monitors, the position of the diver, the ROV and the support vessel is monitored. Where the diving station and the ROV complex are located on different support vessels, the data transmission is carried out using wireless systems. Voice communication is carried out by VHF radio.
386. The person in charge of the diving descent always has priority over the person in charge of the ROV descent and the operator (pilot) when performing diving descents jointly with the ROV. The ROV manoeuvres shall be coordinated by the person in charge of the diving descent. The ROV may begin to move only after this has been approved by the person in charge of the diving descent. The person in charge of the diving descent shall report to the working diver the positioning place of the ROV and, when the ROV is manoeuvring, the direction of its movement.
387. When there is a change in the position of the diver and (or) the ROV relative to the support vessel, the information shall be transmitted to the master of the vessel and (or) the person in charge of the diving work. Information on the mutual positioning of the diver and the ROV shall be received from the hydroacoustic and/or visual monitoring systems. The situations "the diver and the ROV see each other"; "the diver sees the ROV"; "the ROV sees the diver" are normal during the performance of the work. The situation "the diver and the ROV do not see each other" is potentially dangerous and requires a transition from performing the work to performing actions to ensure the safety of the diver. A failure in the visual and hydroacoustic positioning of the ROV relative to the position of the diver may pose a particular danger. In this case, the diver is given the command to stop work, look around and check that the cable-and-hose bundle is clear. The diver may resume work only after reporting to the person in charge of the diving descent that there are no obstacles to the diver's return to the descent line or to the diving stage (onto the platform of the diving bell).
388. During joint work of the diver and the ROV, responsibility rests with: (a) the ROV operator (pilot) - for the safety of the current position of the ROV relative to the working diver; (b) the working diver - for his own safe current position relative to the ROV. Where divers and the ROV performing different tasks are in the water simultaneously, their working zones and the approaches to them shall not intersect. Responsibility for coordination at the place of work rests with the person in charge of the diving work and the person in charge of the ROV descent.
389. Activations of the alarm signalling of the ROV's electrical equipment shall be reported immediately to the person in charge of the diving descents.
390. When carrying out diving work jointly with a remotely operated uncrewed underwater vehicle, the additional dangerous and harmful production factors are: (a) manoeuvring of the ROV in the immediate vicinity of the diver; (b) parts of the body, the diver's diving gear or other equipment getting caught in the propellers; (c) the descent (lifting) of the ROV while the diver is underwater; (d) entanglement of the cable-and-hose bundle, hoses, cables, the guides of the diving bell or diving stage, and the working lines running to the diver, with the ROV cable; (e) injury to the diver upon direct contact with the rotating elements and working parts of the ROV; (f) damage to the cable-and-hose bundle upon direct contact with the rotating elements and working parts of the ROV; (g) electric shock; (h) pinning of the diver and (or) his cable-and-hose bundle against underwater objects by the working ROV; (i) failure of the ROV's positioning system; (j) the passing by the ROV manipulators to the diver of objects that sharply change his buoyancy; (k) negative or positive buoyancy of the objects passed to the diver by means of the ROV; (l) loss of the ROV's position relative to the diver.
391. When carrying out diving work jointly with an ROV, the following shall be prohibited: (a) performing the descent and lifting of the diver and the ROV simultaneously; (b) simultaneous movement of the diver and the ROV to or from the point of work; (c) the diver crossing from one side of the ROV to the other, over or under the ROV, irrespective of whether the ROV is moving or stationary; (d) using the ROV for the direct lifting of an "emergency" diver; (e) changing the technology and (or) method of work that leads to a change (reduction) in the safe distances between the diver and the ROV and in the working zones established before the diver's descent; (f) the descent and lifting of the diver by the ROV cable, where this is not provided for by the ROV operating instructions; (g) using the cutting or sawing working parts of the ROV on ropes and cables while the diver is at the place of work; (h) compensating, by the independent buoyancy of the ROV, for objects passed into the diver's hands; (i) manoeuvring the ROV above the diver and directly behind the diver; (j) simultaneous use of the ROV together with divers during underwater blasting work and for the underwater search and lifting of explosive objects.
392. When carrying out diving work jointly with an ROV, actions shall be provided for to prevent the exposure of workers to additional harmful production factors, which may include: (a) calculation and determination of the safe distances and working zones of the diver and the ROV; (b) calculation of the risks for each stage of the work and each operational procedure; (c) preparation of a plotting board showing on it the position of the place of descent of the diver and the ROV on the support vessel (at the work site) and the underwater situation, indicating the working zones and safe distances; (d) use of hydroacoustic underwater positioning systems for monitoring the position of the divers, the ROV, the deep-water submergence device, the diving bell (diving stage), the tool basket and other objects in real time; (e) use of specialised navigation and hydrographic software during the performance of the work for monitoring in real time; (f) development of procedures for the emergency lifting of the ROV and the emergency lifting of the diver while the ROV is in the water; (g) development and agreement of a table of conventional signals by the ROV lights to ensure the giving of the necessary commands to the diver in the event of loss of communication with him; (h) the diver going around the ROV resting on the bottom by not more than half its length (width); (i) securing the thrusters and fitting them with protective grilles; (j) placing the ROV launch and recovery device at a safe distance from the placement of the diving bell (diving stage) launch and recovery device or the place where the diving ladder is installed; (k) carrying out, in a current, the descent of the ROV downstream relative to the place of descent of the diver, the diving bell or the diving stage; (l) placing, in conditions of limited visibility, on the diver a transponder beacon of the hydroacoustic underwater positioning system; (m) performing work with the ROV gripper manipulators and passing objects to the diver only where there is continuous visual monitoring of the position of the ROV's working part and monitoring of the diver's position; (n) compensating for the negative or positive buoyancy of the objects passed to the diver by additional floats or weights resistant to the effect of hydrostatic pressure at the working depth; (o) using a method of descent of the diver and the ROV in which the diver's cable-and-hose bundle and the ROV cable are in mutually opposite directions on a single conventional line perpendicular to the tension vector of the rope or cable being paid out (received); (p) passing into the ROV gripper manipulator, and receiving objects from the ROV, while being in the frontal projection of the ROV, in front of the video cameras and on the commands of the person in charge of the diving descent; (q) passing (taking) objects, while holding them with both hands as far apart as possible on either side of the gripper manipulator. The need to apply specific actions is determined by the results of a risk assessment depending on the conditions and nature of the diving work.
393. To prevent electric shock to the working diver, the following shall be done: (a) the presence of circuit breakers on the insulation resistance monitoring line shall be ensured; (b) the equipment and elements of the ROV operating under high voltage (junction boxes, transformers and the like) shall have marking visible to divers.
394. The ROV is the first to be lowered underwater and moved into the working zone, and only after this is the descent of the diver (the diving bell or diving stage) and the movement of the diver into the working zone carried out, while the lifting is carried out in reverse order. The ROV's withdrawal from the diver's place of work is carried out on a heading opposite to the heading of approach. When using the ROV for additional lighting of the diver's place of work, the switching on and off of the lights shall be carried out on the diver's command. The withdrawal of the ROV from the working zone, where a deep-water lifting device (hereinafter - DWLD) is used, and its lifting are carried out only after the start of the lifting of the diver (the diving bell/diving stage). When using the ROV without a DWLD, the withdrawal of the ROV from the working zone and its lifting are carried out after the completion of the lifting of the diver (the diving bell or diving stage) onto the deck (the diver's place of descent).
395. To assess the danger of entanglement with the diving bell (diving stage) or with their guide ropes and the diver's cable-and-hose bundle, continuous monitoring of all devices located underwater shall be established. The descent and lifting of the ROV is carried out only in agreement with the person in charge of the diving descents and with his permission. Changes in the position of the ROV and the switching on of the overboard devices and hydroacoustic equipment are agreed in advance with the person in charge of the diving descent, and the working diver is warned of the ROV's actions. The control of the movement of the underwater vehicle (including starting to move from a spot, stopping, approaching the diver and changing position) is carried out only after the diver has withdrawn from the ROV, when the ROV is within the diver's field of view and on his command. The switching on of the drives of the manipulators and other mechanisms projecting from the body of the underwater vehicle is performed only on the command (signal) from the diver.
396. When performing diving descents jointly with an ROV, the following main interaction algorithms are used, each having its own particular features with regard to the safety of their application: (a) "the ROV supports and monitors the descent and work of the diver"; (b) "the ROV supports the performance of the work by the diver"; (c) "the diver supports and monitors the work of the ROV". This algorithm may be applied in all cases, provided that the limitations on maintaining the safe distance and on preventing the intersection of the working zones between the diver and the ROV are observed, and provided that there is continuous monitoring of their position relative to each other. (d) "the diver assists the ROV in the event of an emergency situation". This algorithm may be applied where its justified expediency is established, at working depths accessible to the diver, for the search, release and preparation for lifting to the surface of the ROV, and provided that the supply of electric power to the ROV's consumers is switched off. (e) "the ROV assists the diver in the event of an emergency situation". This algorithm may be applied in all cases, provided that the special requirements for safe manoeuvring (positioning) of the ROV in the immediate vicinity of the diver are observed and measures are taken to exclude contact of the rotating elements and working parts of the ROV with the diver and the elements of the diving gear. (f) "the ROV performs the work instead of the diver" - may be applied in all cases without restrictions.
397. The specific features of carrying out diving work jointly with an ROV, depending on the type (class) of the ROV and the specific conditions of the production activity, shall be taken into account in the process charts, the production planning documents and the instructions (guides, standards) developed by the organisation performing the diving work.
398. When carrying out diving work, various tools and fittings may be used, the main ones being: (a) manual; (b) manual pyrotechnic; (c) mechanised, including electrified, hydraulic and pneumatic.
399. Tools, when performing diving work, shall be used with the provision of safety measures that exclude injury to the diver. The requirements for safe operation of tools for performing diving work shall be contained in the labour protection instructions. Periodic maintenance and repair of tools are carried out in accordance with the requirements of the operational documentation of the tool manufacturer and are planned within the diving equipment maintenance system. The results of inspections, repairs, checks, tests and technical examinations of tools (with the exception of manual tools) are entered in the log of accounting, inspection and testing of tools and fittings.
400. Divers who have undergone training in the safe methods and techniques for performing work with the use of tools may be admitted to diving work with the use of tools. Divers who have an electrical safety group of not lower than II may be admitted to work with electric tools. The connection (disconnection) of auxiliary equipment (transformers, frequency converters, residual current devices) to the mains, its checking, and also the elimination of faults are performed by electrical personnel.
401. A diver assigned to work underwater shall personally inspect the tools with which he is to work and verify their serviceability by a trial switching-on. Tools and fittings, other than manual ones, lowered underwater shall be suspended on a separate rope (working line) or placed in the diving stage (tool basket). After the completion of the diving work, the tools shall be raised out of the water.
402. When carrying out diving work with the use of tools, the additional dangerous and harmful production factors are: (a) the movement of the moving parts of various tools and equipment; (b) breach of the insulation of electrical circuits; (c) the use of tools, grinding and cutting wheels not intended for work in water or in seawater; (d) the appearance of faults in tools during work underwater; (e) the falling of tools when passing them to the place of work or lifting them; (f) loss of tools underwater; (g) breakage of hoses or their accidental pinching by tools and fittings; (h) leakage of oil when working with hydraulic tools; (i) destruction of the working parts of the tool; (j) the entry of the cable-and-hose bundle and elements of the gear into the working zone of the tool's working part; (k) the diver being torn away from the workplace by the current, the cable-and-hose bundle and the working hoses when they are under tension; (l) the performance of work in hard-to-reach and confined spaces, in conditions of no visibility underwater and sub-zero temperatures on the surface.
403. When carrying out diving work with the use of tools, the following shall be prohibited: (a) leaving a tool in the switched-on (operating) position during a break in work, when carrying a tool from one workplace to another, or when the diver moves to another workplace; (b) switching on the drive, changing the rotational speed, supplying electricity and working media without a command from the diver; (c) working underwater when faults appear (are detected); (d) directing the jet of a water-pressure tool at oneself or towards another diver, as well as receiving from or passing to the supporting diver a tool that is switched on; (e) working without checking and measuring the resistance; (f) working with electric tools in non-watertight diving overalls and diving suits or "wet"-type suits; (g) replacing the working part (including drills, chisels) while running, before it has come to a complete stop, and operating a powered tool with a poorly secured working part; (h) touching or taking in the hands the rotating or reciprocating working part of a powered tool; (i) passing a tool by holding it by the hose or electric cable; (j) holding a tool by the protective casing, hose or electric cable; (k) stopping the supply of air (working medium) by kinking the hose or tying a knot; (l) switching on a tool without the working part or with the working part inserted but not pressed against the surface being worked; (m) working with a tool whose period for the next test or maintenance has expired, or when faults arise; (n) leaving a hand-held pyrotechnic tool and its cartridges unattended; (o) removing a "misfired" cartridge underwater and/or reusing it.
404. When carrying out diving work with the use of tools, actions shall be provided for to prevent the exposure of workers to additional harmful production factors, which may include: (a) tools and appliances shall be positioned at the workplace, delivered to the diver and raised from the diver in such a way as to exclude the possibility of their rolling off and falling; (b) during the transport and/or delivery of tools and appliances, their injury-hazardous (sharp, pointed, cutting) parts and components shall be isolated to ensure the safety of workers; (c) during breaks in work and during movements, the supply of air, liquid or current shall be switched off and the tool held with its working part away from oneself; (d) delivering the tool directly to the place of work; (e) suspending and securing small-sized hand tools with lanyards or carabiners to the diver's harness; (f) using a tool basket to deliver tools to the place of work; (g) using a diving stage for stowing and securing tools and appliances; (h) during work, the diver shall hold the tool by the handle and use safe working positions; (i) before switching on, ensuring removal to a safe distance from the working part and the cleanness of the cable-hose bundle and other elements of the diving gear and machinery; (j) determining the diver's place of work in relation to the descent point in such a way that the direction of the cable-hose bundle excludes its entry into the zone of the working part, and so that it is behind the diver and has no slack; (k) adjusting tools, making settings and replacing working parts at the surface; (l) installing hoses to remove the exhausted air (working medium) from the diver's work zone underwater; (m) using gloves and other additional protective means for the diver; (n) using dry cutting discs that have not previously been exposed to water; (o) earthing the body of the power tool; (p) connecting the hose to the main line and the tool, and disconnecting it, with the shut-off valves closed; and the hose shall be positioned so as to exclude the possibility of its accidental damage or pinching by the supporting watercraft; (q) charging the hand-held pyrotechnic tool at the surface. For work with electric tools, only watertight diving dress and "dry"-type diving overalls shall be used. The need to apply specific actions is determined based on the results of the risk assessment, depending on the conditions and nature of the diving work.
405. The specific features of carrying out diving work with the use of tools and appliances shall be taken into account in the process flow charts, production planning documents and in the instructions (guidelines, standards) developed by the organisation performing the diving work.
406. The provision of safety during underwater blasting operations (hereinafter - UBO) shall comply with the requirements of the current Federal Norms and Rules on safety in blasting operations.
407. Organisations conducting underwater blasting operations (work with explosive materials) shall have trained personnel: performers and persons in charge of blasting operations holding unified blaster's books.
408. Divers who have completed the following may be admitted to the independent performance of underwater blasting operations: (a) vocational training in the occupation of "diver"; (b) training as a blaster with the right to conduct blasting operations; (c) a knowledge test on safe methods and techniques for performing underwater blasting operations.
409. Workers who have completed the following may be admitted to the supervision of underwater blasting operations: (a) training as a person in charge of diving work; (b) training as a person in charge of blasting operations.
410. During underwater blasting operations, the additional hazardous and harmful production factors are: (a) the presence of ships, watercraft and people, both in the water and on the shore, within the boundaries of the danger zones; (b) the use of explosive materials and means of initiation or detonation that are not intended for underwater blasting operations, have expired shelf lives or are in a faulty condition; (c) manoeuvring of ships and watercraft in the area where underwater blasting is conducted; (d) damage to or displacement of explosive materials during transport and delivery to the descent site; (e) unreliable fastening of the means of initiation or detonation to the explosive materials during preparation of the charge; (f) impairment of the serviceability of the electric blasting network and of the procedure for connecting to the current source; (g) entanglement of the elements of the blasting network with the diver's cable-hose bundle. The list of specific actions to prevent the exposure of divers to hazardous and harmful production factors is determined based on the results of the risk assessment, depending on the conditions and nature of the diving work, when developing the blasting operations project.
411. The conduct of UBO shall be prohibited when the wave action of the water surface exceeds 2 points (sea state scale) and the wind force exceeds 4 points (Beaufort scale). If weather conditions deteriorate beyond the parameters indicated above, underwater blasting operations shall be stopped immediately.
412. The specific features of carrying out UBO shall be taken into account in the process flow charts, production planning documents and in the instructions (guidelines, standards) developed by the organisation performing the diving work.
413. When performing underwater welding and cutting work at hazardous production facilities, the requirements for the organisation of welding operations shall be observed.
414. Divers may be admitted to perform underwater welding and cutting work if they hold: (a) vocational training in the occupation of "diver"; (b) vocational training in the occupation of "welder"; (c) a valid welder's certification certificate for the relevant welding method or a qualification certificate for performing underwater welding and cutting work; (d) a record of the knowledge test on safe methods and techniques for performing underwater welding (cutting) work. When performing work using high-technology welding and cutting methods (plasma, thermal, laser, friction stir), a specialist in the welding and cutting method being used shall be involved in the knowledge test on safe methods and techniques for performing the work.
415. Welding (cutting) work is performed in accordance with a written order - a permit to work for the performance of high-hazard work, issued by officials authorised by the employer and responsible for the organisation and safe performance of high-hazard work. The permit to work specifies the content, place, time and conditions for performing the work, the composition of the diving station and the workers responsible for the organisation and safe performance of the work. Work involving underwater welding and cutting is performed according to process flow charts on the basis of production planning documents. Before the process flow chart is developed, a diving survey is carried out of the object (the underwater part of the object) of the upcoming work, as well as of the adjacent area of the ground, if the object is located on the ground. During the inspection, particular attention shall be paid to the condition of the structure (hull), the possibility of access to the place of work, the need to prepare the site for work, and the presence and location of explosive items and containers (rooms, compartments, cisterns).
416. When preparing for the work, hazard identification and risk assessment shall be carried out on the basis of the specific conditions of performance, the nature of the work and the features of the object; the necessary measures for their reduction and/or elimination, as well as actions in the event of emergency situations, shall be provided for. When performing underwater welding and cutting work, the diving station shall have at least 4 divers in its composition, and when working with the use of welding chambers (caissons), at least 5 persons. One of the supporting divers shall be separately assigned to control the supply and disconnection of electric power in the underwater welding circuit, to adjust the feed of the welding wire, to supply oxygen to the cutter's hose, to monitor the readings of the electrical measuring instruments, to adjust the current strength, to monitor the readings of the oxygen reducer's pressure gauges, and to prepare electrodes for handing over to the working diver. When working in a welding chamber, one supporting diver shall be at the entrance (exit) of the welding chamber (caisson) in immediate readiness to act in the event of an emergency situation.
417. When performing underwater welding and cutting work, the additional hazardous and harmful production factors are: (a) the location of the diver's place (section) of work in hard-to-reach places; (b) unsatisfactory conditions for carrying out the work (visibility, current, illumination, depth); (c) the danger of electric shock to the diver; (d) the danger of contact with and burn-through of elements of the diving gear; (e) interruption or failure of communication with the diver during work; (f) the effect of the arc on the diver's eyes; (g) interruption of the supply of air (breathing gas mixture) for inhalation in the event of an abnormal situation; (h) changing electrodes without disconnecting the welding circuit and receiving confirmation of this; (i) the reliability of the fastening of the oxygen cylinders and their protection (removal) from external sources of danger; (j) mechanical damage to and the effect of temperatures on the welding cables laid in the passages near the descent point (along the deck); (k) accumulation of gas bubbles near the diver, under structures overhanging the diver; (l) impairment of the position and/or serviceability of the disconnector (switch) of the welding circuit; (m) the absence (impairment) of earthing, of insulation on the electrode holder and other current-carrying elements; (n) the position of the diver at various stages of work; (o) a possible change in the position of the structure during cutting or after its completion; (p) the possibility of a fire occurring during welding (cutting); (q) the explosion hazard and ignition in compartments (rooms, cisterns) adjacent to the place of welding (cutting) on the hull, owing to the presence of explosive liquids, gases or other combustible materials, and the accumulation of oxygen and hydrogen in the compartments (in the air cushions of rooms, compartments); (r) the explosion hazard of vessels, containers, pipelines, tanks, cisterns and other containers operating under pressure, containing and/or intended for the transport of readily flammable, explosive liquids, gases and/or their products; (s) ignition of combustible materials on the surface of fully enclosed containers (compartments, cisterns, tanks) partially filled with water; (t) accumulation of an excessive quantity of toxic, asphyxiating, narcotic and explosive gases inside the welding chamber (caisson); (u) violation of the sequence of making the weld seams (sections of surfacing, cutting). The diver is exposed to the greatest danger of electric shock during welding at the initial moment (when a metal element is attached to the object being welded) and during cutting at the final moment (when a metal element is separated from the object being cut). In the event that the working diver reports that he feels signs of electric current passing through his body, the welding current shall be switched off immediately and the diver raised to the surface.
418. When performing diving welding and cutting work, the following shall be prohibited: (a) admitting to work workers who do not have documents on the relevant education (training) and/or qualification; (b) carrying out work without checking the support means and equipment, and the reliability of the earthing of the welding installation and the welding current sources, with a record of the results thereof; (c) carrying out work without earthing the object of work; (d) using diving gear in the self-contained version, or in a configuration that exposes the diver to the danger of receiving electric-shock injuries and of interruption of the forced supply of air (breathing gas mixture) in an abnormal or emergency situation; (e) performing work in the absence or failure of direct two-way voice communication with the diver; (f) touching and replacing an electrode that is under voltage without switching off the current supply; (g) letting go of the electrode holder, placing it on the ground, in the stage or on the object of welding (cutting), or suspending it, without switching off the welding current; (h) passing means for underwater welding and/or cutting, and tools, that have not been de-energised; (i) using the metal of the structure being separated, or water, as the return conductor; (j) carrying out work when the diver feels signs of electric current passing through; (k) taking up a position opposite the cutting line (weld seam) when welding (cutting) on hollow containers, structures and the ship's hull; (l) using alternating current for underwater welding and cutting; (m) using oxygen cutting in half-flooded containers (compartments, cisterns, tanks); (n) carrying out work on vessels, containers and pipelines that are under pressure.
419. When performing diving welding and cutting work, actions shall be provided for to prevent the exposure of workers to additional hazardous and harmful production factors, which may include: (a) checking, before the start of work, the electrical equipment, the reliability of the contact connections of the welding cables, the reliability of the earthing of the welding installation and the welding current sources, the correctness of the connection of the equipment and the polarity of the welding circuit, and the tightness of the hoses; (b) checking the serviceability of the disconnector (switch) for earthing fault of the welding circuit, and checking it at defined time intervals during work; (c) checking the insulation resistance (not less than 0.5 MOhm) and the open-circuit voltage of the welding current source (shall not exceed 110 V); (d) the use of diving gear in the hose-supplied version, which excludes the effect of electric current on the diver through the metal elements of the gear; (e) the use of additional protective means in the form of dielectric gloves and rubber footwear (booties) and a head covering (hood); (f) the use of protective appliances, light filters, darkened viewing glasses to protect the diver's eyes from the harmful effect of the electric arc; (g) the use of a diving stage and other devices for holding at the place of work in the required position; (h) the mandatory presence of a disconnector (switch) for earthing fault of the welding circuit on all equipment supplied with electric power from the surface and located between the power source and the electrode holder (tool); (i) checking the electrical circuit by starting the welding unit and igniting the arc at the surface before the diver descends underwater; (j) checking the oxygen supply by briefly pressing the handle of the control valve before the diver descends; (k) the supply and disconnection of electric power in the underwater welding circuit shall be carried out only on the command of the working diver or on the command of the diving descent supervisor: "Current on!", "Current off!"; (l) the use of welding installations with switching (disconnecting) and protective electrical apparatus; (m) determining the location of the welding unit on the basis of a calculation of the optimum length of the welding circuit and the loss of electric power; (n) fastening the return conductor (earthing) as close as possible to the place of welding (cutting) on the object of work; (o) cleaning off corrosion and preparing the fastening point of the return conductor (earthing) to reliably ensure electrical contact with the metal structure; (p) the use of mechanical clamps and cramps for fastening the return conductor; (q) timely transfer (re-fastening) of the return conductor during work; (r) fastening the structure before the start of welding (cutting), where there is a danger of a change in position (collapse), by means of slings or other means (stops, guys); (s) determining the sequence of cutting and the weight and size parameters of the structures being separated; (t) checking the compartments (rooms, cisterns) adjacent to the place of welding (cutting) on the hull of the ship (installation, object) for the absence in the compartments of explosive liquids or combustible materials, and checking the air composition in them for explosion hazard; (u) cleaning (purging, washing, steaming, ventilation and other means) of the residues of combustible liquids and vapours until they are completely removed, before the start of welding (cutting) of vessels, containers, pipelines, tanks (compartments) of tanker ships, cisterns and other containers containing flammable and explosive substances; (v) relieving (equalising) the pressure and filling the containers (vessels, cisterns, pipelines, tanks, compartments) with water or inert gases that do not support combustion; (w) equipping the welding chambers (caissons) with systems for monitoring the gas (air) environment, video monitoring and life support. The need to apply specific actions is determined based on the results of the risk assessment, depending on the conditions and nature of the diving work involving welding and cutting.
420. The measures to prevent the accumulation of explosive gases when the diver performs work involving welding and cutting include: periodic change of position by the diver, cutting openings in overhanging structures, ventilation and removal of gases from compartments (rooms, cisterns).
421. Direct current shall be used for performing underwater electric welding work. In the event of a failure of voice communication, the current supply shall be switched off immediately and the diver's condition requested by a prearranged signal. To avoid contact with and burn-through of elements of the diving gear, and especially the helmet, the diver shall hold the electrode holder with the electrode away from himself. The position of the diver shall be stable while allowing it to be changed periodically and, at the same time, excluding the possibility of the diver being between the weld seam (cutting line) and the electrode; and when working on hollow structures and the ship's hull, it shall be to the side of the cutting line (weld seam), so that in the event of an explosion inside the compartment the blast wave is directed past the diver.
422. The disconnector (switch, interrupter, enclosed-type knife switch, contactor, circuit breaker) for earthing fault of the welding circuit shall be kept disconnected (open) at all times, except during the welding (cutting) process. The location of the disconnector shall provide visual control of the "on" and "off" positions, proximity to the communication panel with the working diver, and shall be within easy reach of the person responsible for the disconnector. Equipment controlled in automatic and/or programmed modes shall be equipped with a mechanical disconnector satisfying these requirements.
423. The serviceability of the equipment for performing welding work is checked at least once every 6 months by workers appointed by the employer as responsible for keeping the relevant type of equipment in a serviceable condition. Repair and elimination of faults shall be carried out by the workers responsible for keeping the relevant type of equipment in a serviceable condition who have completed training and been admitted to this work.
424. Before performing welding and cutting work in compartments (cisterns, rooms with an air cushion) or on the hull of a ship (floating installation), in places adjacent to such rooms, the air composition shall be checked for explosion hazard, as well as for the absence in the compartments of explosive liquids or combustible materials. The procedure for the preparation, admission and performance of underwater welding and cutting work at objects where flammable and explosive substances are contained shall be determined by the operational and/or design documentation for these objects. Where it is necessary to perform work in fully enclosed containers (compartments, cisterns, tanks) that are partially filled with water, and there is a danger of ignition of combustible materials on the surface, the containers shall be opened from the top; in this case the flash point of the combustible material floating on the water surface shall be above 450 °C, and the height of the water column above the place of the weld seam (cutting line) shall be not less than 1 m.
425. The internal volume of welding chambers (caissons) shall provide unobstructed access for two divers, one of whom is the working diver and the second the supporting diver. If the design of the caisson and the nature of the work presuppose the performance of work by two divers, the diving descent supervisor shall determine the place for each diver on safety grounds, and one more diver (the standby diver) shall be at the entrance (exit).
426. The specific features of carrying out diving work during the performance of work involving welding and cutting shall be taken into account in the process flow charts, production planning documents and in the instructions (guidelines, standards) developed by the organisation performing the diving work.
427. Depending on the flooding conditions, the size of the object, the nature of the damage and the chosen method of raising, the technologies, technological and production processes shall be determined with reference to the specific conditions for carrying out ship-raising work, on the basis of which the requirements for the qualification of divers are determined. Divers who have completed targeted labour protection instruction are admitted to the performance of diving work in ship-raising. The safety requirements for the performance of diving work in ship-raising shall be contained in the ship-raising project, the production planning documents and the labour protection instructions developed with reference to the specific conditions and nature of the work in ship-raising.
428. During diving work in the course of performing ship-raising work, the additional hazardous and harmful production factors are: (a) falling through open hatches, breaches; (b) becoming entangled in the rigging, lifting cables and ropes, deck mechanisms and damaged structures of the ship; (c) crushing, pinching and rupture of the cable-hose bundle; (d) burying of the diver by ground, cargo, dismantled mechanisms and mechanisms torn from their places; (e) destruction of bulkheads and decks under the effect of loads; (f) destruction of assemblies and points at the places where lifting forces are applied; (g) sudden falling of poorly secured, overhanging items and cargo or ones that have torn loose from their places, as well as of jammed items that tend to float up; (h) the presence of the diver or elements of his gear on the line of movement of the lifting cable or rope; (i) injury by load-lifting mechanisms, devices and load-bearing connections; (j) breakage of slings, ropes, cables and other load-bearing connections operating under load; (k) collapse of the ground during the washing-out of tunnels under the ship's hull, or a change in the position of the ship on the ground; (l) accumulation of ground in the tunnel behind the diver; (m) accumulation of toxic and explosive gases in the air cushion of compartments, cisterns and rooms; (n) a change in the position of the ship-raising slings on the hull or in the tunnel; (o) a change in the position of the steel ship-raising pontoons after tightening, partial or full blowing-out; (p) uneven distribution of the load and lifting forces; (q) loss of local or overall longitudinal strength; (r) uncontrolled surfacing of the sunken ship or of ship-raising devices and lifting means; (s) a change in the position of the ship or the load-bearing connections after surfacing (raising) due to the effect of wind and wave action; (t) reverse flooding after the partial or full surfacing of the ship to the surface.
429. During ship-raising diving work, the following shall be prohibited: (a) descending and ascending on a cargo or under-cutting rope, a ship-raising sling and other load-bearing connections that are under load; (b) carrying out the under-cutting (drawing through) of a rope (cable) under the hull of a sunken ship by means of surface craft while the diver is in the water; (c) performing unloading work when the wave action of the water surface at the place of work exceeds 2 points, and the unloading of explosive cargoes when the wave action exceeds 1 point; (d) carrying out diving descents before the completion of the full blowing-out of the ship or pontoons, and the full pumping-out of water from the ship.
430. During the survey of a sunken ship, the taking of the most important measurements and the inspection of individual parts, assemblies and components of the sunken ship is carried out twice by different divers. The first descent to the sunken ship shall be carried out by the most experienced diver. The survey of the sunken ship shall be carried out in accordance with a pre-developed programme for the survey of the sunken ship.
431. The unloading of explosive and chemically hazardous cargoes (ammunition, explosive materials, combustible liquids, gases, poisonous and toxic substances) shall be carried out in accordance with specially developed process flow charts. Safety measures and the requirements for the safe operation of the process equipment used shall be contained in special instructions and labour protection instructions. Divers assigned to the unloading of explosive and chemically hazardous cargoes shall undergo targeted instruction.
432. The safety requirements for work with steel ship-raising pontoons and pontoons with flexible shells are established in the instructions (guidelines, standards) of the organisation operating the equipment, depending on the type of equipment used. The specific features of carrying out diving work at the various technological stages of ship-raising shall be taken into account in the ship-raising project, in the process flow charts, production planning documents and in the labour protection instructions developed by the organisation performing the diving work. The list of specific actions to prevent the exposure of divers to hazardous and harmful production factors is determined based on the results of the risk assessment, depending on the conditions and nature of the diving and ship-raising work.
433. Divers and rescue divers who have a command of rescue techniques and methods of providing first aid to victims are admitted to diving work for the rescue of people.
434. The performance of rescue work in searching for and providing assistance to people in distress on the water by rescue divers is carried out in inland water areas and coastal areas of the seas. The person in charge of the search-and-rescue work is responsible for the safe organisation, compliance with labour protection requirements and the performance of the diving rescue work. To supervise diving work during the performance of rescue work, subject to their having completed training, the following heads and their deputies may be admitted: (a) of the rescue station; (b) of the mobile search group; (c) of the search-and-rescue formation on the water area; (d) of the search-and-rescue diving detachment; (e) of the search-and-rescue detachment (subdivision). To ensure the performance of diving descents, a staff or non-staff diving station is manned and a diving post is equipped. During short-term emergency diving descents (work), the diving post need not be equipped. Diving rescue work shall be performed in diving gear corresponding to the conditions of the diving descents, taking into account the nature of the rescue work and the results of the risk assessment. A working check of the gear is carried out by the divers on each coming on duty, and also immediately before the descent if the gear has been transported to the descent site by road or other transport. The degree of readiness of the working and standby divers and their location are established by the diving descent supervisor. The organisation and procedure for carrying out rescue diving work and diving work at rescue stations and search-and-rescue detachments (formations), depending on the specific conditions of activity, may be supplemented depending on the specific conditions within the framework of the labour protection management system's procedure for responding to accidents, incidents and occupational diseases.
435. Emergency rescue diving work is carried out without a work plan and in the following cases: (a) for the purpose of rescuing people; (b) when providing assistance to ships (boats) in distress, and in the emergency ditching of aircraft in inland water bodies; (c) when performing work necessary to prevent a catastrophe, an industrial accident or a natural disaster; (d) when performing socially necessary work to eliminate unforeseen circumstances that threaten the life or normal living conditions of the population; (e) when performing work the need for which is caused by the introduction of the "Emergency Situation" regime.
436. During diving rescue work, the additional hazardous and harmful production factors are: (a) surf wave when towing the casualty to the shore; (b) moving ice; (c) littering of the water surface; (d) the unstudied nature of the body of water; (e) abundant underwater vegetation; (f) limited visibility underwater and current; (g) siltation and cluttering of the bottom; (h) reduction of visibility, up to its complete loss, when silt deposits on the bottom are stirred up; (i) sharp fluctuations in water temperature; (j) the relief of the bottom and the dive profile; (k) manoeuvring of watercraft under motor in the area of search and inspection; (l) unidentified or hazardous items (objects), or structures underwater; (m) psychological unpreparedness to work with the body or fragments of bodies of the deceased; (n) the presence of representatives of hazardous fauna; (o) explosive items underwater. (p) lack of time to study the conditions of the descents. During diving rescue work, the following shall be prohibited: (a) towing of the casualty to the shore by a diver when there is a surf wave; (b) carrying out diving work to eliminate the consequences of a catastrophe, industrial accident or natural disaster, and to inspect and clean places of mass recreation, without a work plan. When diving rescue work is carried out, at the diver's descent site there shall be a watercraft with rescuers and a standby diver (the decision on the use of the watercraft is taken by the diving descent supervisor in accordance with the situation). Additional safety measures during diving rescue work: (a) identification of hazards and risk assessment for diving rescue work in conditions of accidents, natural disasters, when there is moving ice, a fast current (over 1 m/s), littering of the water surface with floating items, and also in unstudied bodies of water; (b) development of standard compensating actions for the most typical rescue diving work; (c) assignment of the most experienced divers to work of increased risk.
437. The specific features of carrying out rescue diving work shall be taken into account in the standard process charts and instructions (guides, standards) developed by the organisation carrying out rescue diving work. The list of specific actions to prevent the effect of hazardous and harmful production factors on rescue divers (divers) is determined by the results of the risk assessment depending on the specific conditions of the production or service activity.
438. Divers who have command of the safe methods and techniques for performing the simplest diving work are admitted to diving work for the inspection and cleaning of the bottom of the water area: slinging and lifting of sunken items, use of simple hand tools and lifting appliances and devices.
439. The organisation of diving work in the survey and cleaning of the bottom of the water area depends on the affiliation of the water area (on enclosed bodies of water, on inland waterways, in river or sea conditions). The specific features of carrying out diving work in the survey and cleaning of the bottom of the water area shall be taken into account in the instructions (guides, standards) developed by the organisation carrying out the diving work. The list of actions to prevent the effect of hazardous and harmful production factors on working divers during diving work for the inspection and cleaning of the bottom of the water area shall be included in the production planning documents and in the process charts.
440. Descents to perform the inspection and survey of the bottom of the water area at depths of up to 20 m may be conducted using self-contained diving equipment with an open breathing circuit. Where it is necessary to use diving equipment in self-contained mode at depths of more than 20 m, the decision is taken by the diving descent supervisor on the basis of the risk assessment.
441. A diver swimming in self-contained diving equipment with an open breathing circuit shall be accompanied by a watercraft (boat) with a backup propulsor. The diving descent supervisor and the standby diver shall be positioned in the watercraft. When self-contained diving equipment is used, a control line with a float, secured to the diver, is used, and/or hydroacoustic communication means are used for communication with the diving descent supervisor and short-range hydroacoustic devices for monitoring the position of the working diver. If communication with the working diver is lost, the standby diver shall immediately descend underwater along the control line. The watercraft (boat) shall have a means for giving prearranged sound signals to the diver.
442. During the survey and cleaning of the bottom of the water area, the additional hazardous and harmful production factors are: (a) limited visibility underwater and current; (b) siltation and cluttering of the bottom; (c) entanglement of the diver; (d) the extent, conditions and relief of the shoreline; (e) loss of orientation, direction and location by the diver; (f) loss of control over the diver's location by the diving descent supervisor and the support personnel; (g) the relief of the bottom and the dive profile; (h) manoeuvring of watercraft under motor in the area of search and survey; (i) unidentified or hazardous items (objects), or structures underwater; (j) an unknown or unstudied underwater situation; (k) reduction of visibility, up to its complete loss, when silt deposits on the bottom are stirred up; (l) sharp fluctuations in water temperature; (m) the presence of representatives of hazardous fauna; (n) explosive items underwater.
443. During diving work in the survey and cleaning of the bottom of the water area, the following shall be prohibited: (a) to choose a search method with intersecting routes of movement of divers and/or of a diver and a technical inspection device; (b) to carry out any work with items posing a danger of explosion and/or pollution and contamination of the environment and/or with unidentified items whose purpose and properties have not been established, and to raise them to the surface.
444. During diving work for the survey and cleaning of the bottom of the water area, actions are provided for to prevent the effect on workers of additional harmful production factors, which include: (a) the use of search methods and technical means for detecting items without the use of divers' labour: trawling, underwater television, acoustic means, metal-detection devices, sonars, echo sounders, profilographs, remotely operated and autonomous underwater vehicles; (b) the choice of a rational method of survey, search and route of the diver's movement depending on the conditions of the descents, the area of the survey, the size of the objects or items being searched for and the transparency of the water; (c) making the calculation of the area of search and/or survey; (d) the installation of surface and underwater landmarks. The list of specific actions to prevent the effect of hazardous and harmful production factors on divers is determined by the results of the risk assessment depending on the conditions of carrying out the diving work. If an explosive item is detected and/or a suspicion arises that the detected item poses a danger of explosion, chemical pollution or contamination of the environment, the diving descent supervisor shall immediately raise the divers and notify the Unified Duty and Dispatch Service of the local self-government body or the port administration to take urgent measures. The place where the item is detected shall be enclosed with floats, and its exact coordinates shall be established and recorded. The specific features of carrying out diving work for the search and lifting of explosive items shall be taken into account in the standard process charts and instructions (guides, standards) developed by the organisation carrying out the diving work.
445. Diving work at public recreation areas is carried out to prevent injuries and ensure the safety of people on the water and includes the following types of diving work: (a) survey and cleaning of the bottom of the water areas of beaches; (b) search for and lifting from the water of fragments (items) of reinforced-concrete, metal and wooden structures, sunken logs, tree roots, stones, glass; (c) dismantling (sawing down) of pile structures without the use of cutting and welding underwater; (d) cleaning of the bottom of bathing areas of silt, algae and sediment.
446. Divers who have studied the design, operating rules and safe methods and techniques of work on underwater propulsion devices (hereinafter - UPD) may be admitted to operating UPD. The specific features of carrying out diving work when performing tasks (operating) on UPD shall be established in the instructions (guides, standards) developed by the organisation carrying out the diving work. The list of specific actions to prevent the effect of hazardous and harmful production factors on divers is determined by the results of the risk assessment depending on the specific conditions of the production or service activity.
447. Divers who have passed a knowledge check on the safe methods and means of performing work in the specific conditions of the production activity are admitted to performing diving work in commercial fishing, in the harvesting of seafood, at places of artificial keeping and breeding of aquatic organisms and aquaculture (hereinafter - in commercial fishing and in the harvesting of seafood). The following is appointed as the diving work supervisor: (a) for descents from a vessel and using the vessel's watercraft in the vessel's support - the master of the vessel, who has undergone training in supervising diving work; (b) for descents from a group of small watercraft - an appointed official, from among the organisation's regular employees, who has training in supervising diving work; (c) for descents from the shore, a pier, a working platform and other structures - an appointed official from among the organisation's regular employees, who has undergone training in supervising diving work; (d) for descents in aquariums - an appointed official from among the organisation's regular research staff, who has undergone training in supervising diving work, or diving specialists of the organisation. To supervise the diving descents, one of the divers who has undergone the appropriate training and been admitted to supervising descents by an order of the employer is appointed. The person responsible for organising the safe performance of diving work in the harvesting of seafood is the employer.
448. During diving work in commercial fishing and in the harvesting of seafood, the additional hazardous and harmful production factors are: (a) unreliable holding of the vessel in the area of the diving work and/or changes in the environmental situation; (b) simultaneous conduct of diving work together with work connected with fishing and/or the harvesting of seafood; (c) harvesting or fishing gear lowered overboard, or barriers artificially placed in the water, which pose a threat of injury; (d) movement of small watercraft under motor while the diver is underwater; (e) discrepancy between the actual depth of the descents and the planned depth, or loss of control over the descent time; (f) diving descents in the tidal zone, in conditions of waves running up onto the shoreline or of swell; (g) harvesting of seafood on rocky formations, in narrow crevices and under overhanging rocks and other objects; (h) movement of the diver in the immediate vicinity of cables, rigging, floats, grow-out ropes of cages, collectors and installations for breeding seafood and growing plants; (i) the arbitrary, non-fixed shape of artificial barriers at places of breeding, keeping or growing of aquacultures; (j) movement of the diver within the confined space of artificial places for keeping fish and mammals; (k) the presence, at places of artificial breeding and growing, of food additives, salts and supplementary feed whose concentration poses a danger to the diver; (l) disorientation of the diver by the irregular movement of the farm net, by the shadow it casts, and by the movement of fish; (m) disturbance of the thermal balance before the descents, during their conduct and after the descents, when positioned in the support watercraft.
449. When diving work for the harvesting of seafood and at places of artificial keeping and breeding of aquatic organisms is performed by divers, the formation of a diving station is mandatory. Before the start of the work, a permit to work shall be drawn up and the functional duties for the period of the diving descents shall be defined. A diving descent supervisor, working divers, a standby diver and support divers are appointed. The conduct of diving work with a diving station composition of fewer than three persons shall be prohibited.
450. During diving work for the harvesting of seafood, at places of artificial keeping, of breeding of aquatic organisms and of aquaculture, it shall be verified that the following actions have been carried out: (a) production planning documents (a plan for carrying out the diving work) have been developed, and the adopted organisation of the conduct of the diving work ensures their safe performance; (b) the support vessel or watercraft has seaworthiness appropriate to the conditions of the work, is able to hold its position in the area of the work and is properly equipped with means of navigation and communication and with equipment for the safe submersion and exit from the water of the diver; (c) the personnel of the diving station and the crew of the vessel have been informed of the possible hazards and have been instructed, and for the divers tables limiting work by depth and time have been developed; (d) the competence of the divers corresponds to the nature of the forthcoming work and the conditions of the descents, and the number of personnel is sufficient for the safe conduct of the diving work; (e) duties and responsibilities have been allocated; (f) the diving work supervisor and the diving descent supervisor have been designated by order, duties and responsibilities have been allocated, and the actions to be taken in the event of an off-normal and emergency situation with a diver have been defined.
451. When instructing the personnel of the diving station, the crew or the team, the following information shall be conveyed: (a) the purpose and features of the dive: the features and character of the behaviour of the animals (aquatic organisms) taking into account the season and the conditions of their habitat; the features of the harvesting and fishing gear used, with an indication of its direction, length and other indicators affecting the safety of the work; the features of the layout and structures of the underwater farm installations at places of artificial breeding of seafood and aquacultures; (b) the procedure for performing the task, the features of movement or swimming; (c) the hazards characteristic of the forthcoming diving work; (d) the procedure of actions in an off-normal and emergency situation and when there is a threat of aggression by the animals; (e) when working with self-contained equipment, to establish the working time at depth and the time and procedure of ascent (exit) to the surface. Specialists in the harvesting or servicing of fishing gear or keeping places, research staff of the organisation or biologist specialists are brought in for the briefings. Every crew member of the support vessel or employee of the facility involved in the diving work shall undergo a briefing at the workplace.
452. The number of divers working in the water at the same time is determined on the basis of the possibilities for their support and for supervising the diving descents. Diving descents in the self-contained mode shall be conducted in pairs. In a pair of divers, a lead diver and a follower diver are appointed. In doing so, the divers working in a pair shall move together and monitor each other's position, and the in-water support diver shall constantly keep the working diver within the field of view, and also monitor the surrounding situation and the behaviour of potentially dangerous animals. The supervision of more than 3 divers by a single diving descent supervisor shall be prohibited.
453. When performing diving work in commercial fishing and in the harvesting of seafood, the following shall be prohibited: (a) to carry out work on the harvesting of seafood in difficult conditions and when the environmental conditions in the fishing area deteriorate; (b) to conduct a dive or ascent while holding on with the hands to fishing or harvesting gear, or to be in the immediate vicinity of nets; (c) to be below the fishing gear, to go inside it, to be between parts of the cable rigging and under appliances being lifted for collecting seafood; (d) to conduct solo dives in a current of more than 0.5 m/s in the self-contained mode without safety means and support from the surface; (e) to use one set of equipment for the breathing of two divers; (f) to conduct a dive in the absence of a plan of action in the event of an emergency situation with a diver.
454. Diving work in commercial fishing in the coastal zone and in the open sea is carried out from a vessel. Diving work from a vessel is carried out from the windward side, to prevent the vessel from bearing down on the watercraft, equipment or divers being lowered.
455. Diving work for the harvesting of seafood and the collection of aquaculture, and for the servicing of places of artificial keeping and breeding of sea animals and mammals in the coastal zone or by the shore is performed with the support of small watercraft and/or from floating objects (working platforms), both manoeuvring in the harvesting area and installed by the place of breeding of seafood and growing of plants on farms, in cages, collectors, baskets and other special installations. The safety measures during diving work are developed taking into account the methods of harvesting, breeding, keeping and growing of seafood, sea animals, mammals or aquacultures used. Hand protection means shall be used, and the selection of equipment shall be carried out so as to minimise protruding parts and fasteners. The diving knife shall have a well-sharpened blade on one side and a serrated shape on the other side. The support watercraft or the working platform shall have special reinforced shears capable of cutting through a net.
456. When working (collecting seafood and aquaculture, inspecting, servicing) near structures and rigging systems consisting of cables, ropes, knots and ties supported by floats or buoys floating on the surface, and by weights, cables and warps held near the bottom, the arrangement of which is difficult to memorise and to make out underwater, the greatest danger lies in the entanglement of divers. During the briefing before the descents, particular attention shall be paid to the layout and design of the installations, and for the descent a pair shall be assigned in which one of the divers has experience of working on that structure. During descents near nets, a position shall be chosen that allows the net to be seen in front of oneself. The distance between the divers shall be set on the basis of safety considerations, so that if one diver becomes entangled the second is to one side and is able to render assistance. Where it is necessary to hook on or hold position underwater, the diver may take hold of the supporting warps or cables held by weights on the bottom. Holding position by taking hold of nets shall be prohibited. The placement of the catch bag on the diving equipment shall not create obstacles to the movement of the diver, a threat of entanglement or a change in the diver's buoyancy during the work. The dive profile and the route of movement shall be chosen in such a way as to avoid entanglement and snagging. Before ascent, it shall be ensured that there are no obstacles to the ascent and no snags. Conducting diving descents until the air supply in the cylinders is completely exhausted shall be prohibited. At the end of the work underwater, a supply of air shall remain in the cylinders in a volume sufficient to switch to breathing from the reserve air supply in the event of an off-normal or emergency situation.
457. If a need for decompression arises in aquariums and places of artificial keeping and breeding of animals, the stay of the divers at the stops at each stage of decompression shall be accompanied by the divers observing each other and the behaviour of the inhabitants. If there are several aquariums and different microflora for the habitation of animals has been created in them, diving equipment is provided for each aquarium. During dives, visual communication signals are used. Only a low-frequency sound may serve as emergency signals that may be given by staff located on the outer side of the aquarium (on the surface) - knocking on the sides of the aquarium, knocking on the glass, knocking on a metal object, if this is possible. The possibility of using emergency prearranged signals shall be agreed with the scientific director of the organisation. For open bodies of water, "emergency" signals using any source of sound may be used. The signals for the emergency exit of the diver shall be designated before the descents. No circumstances may serve as a reason for a diver to dive when there is an unacceptable or intolerable level of occupational risk.
458. During diving work in commercial fishing, in the harvesting of seafood, at places of artificial keeping and breeding of aquatic organisms and aquaculture, actions shall be provided for to prevent the effect on workers of additional hazardous and harmful production factors, which may include: (a) the planning and conduct, as far as possible, of no-decompression descents, and the setting of limits on the depth and time of work; (b) the marking out and designation of the harvesting area; (c) the determination of rational routes of movement, of the dive profile and of the methods of supporting the diving descents; (d) the use of two-way voice communication between the diving descent supervisor and the divers; (e) the use of external landmarks, and also of transponder beacons and other short-range hydroacoustic devices to designate the underwater situation and the fishing and harvesting gear; (f) the use of compasses, navigation panels and other means of orientation; (g) the use of diver protection means, protective devices and/or safety means that exclude the possibility of direct accidental contact with the fishing gear and representatives of the fauna; (h) the raising onto the deck and/or de-energising of the fishing and/or harvesting gear for the period of the diving work; (i) the use of manned and unmanned underwater vehicles for observing the harvesting and the fishing gear; (j) the installation of additional descent ropes with an anchor (weight) and a buoy for orientation and for holding the diver underwater; (k) the use of decompression and marker buoys. The measures to prevent the effect of hazardous and harmful production factors on divers during diving descents in aquariums may be: (a) the use of additional protective clothing of durable fabric, of chain mail against punctures, cuts and bites; (b) the use of additional protection on the protruding parts of the diving equipment to prevent the causing of injury to the inhabitants of the aquarium; (c) the conduct of diving descents for the purpose of servicing (cleaning) aquariums with predators only after the feeding of the animals, when they are sated and pose no threat to the working divers; (d) the maintenance of constant visual communication between the divers. The list of specific actions to prevent the effect of hazardous and harmful production factors on divers is determined by the results of the risk assessment depending on the conditions of carrying out the diving work.
459. Deep-water diving work is performed by organisations that have deep-water diving hardware (a diving complex, technical devices, equipment and diving gear) in serviceable condition and admitted for the performance of work, and a diving service staffed with diving, engineering and technical personnel, personnel for servicing the life-support systems and medical personnel, in a number that ensures the accident-free operation of the complex and determined on the basis of the operating manual of the complex. Diving work at depths of more than 60 m is deep-water work. The methods and means used in deep-water work may also be used at shallower depths. To ensure the safe organisation of the conduct of deep-water diving work, the following shall be developed in the organisation: (a) a guide for conducting deep-water diving descents in relation to the deep-water diving complex used (hereinafter - the DDC); (b) a guide for the medical support of deep-water diving descents; (c) instructions for the safe operation of the deep-water diving hardware and equipment; (d) labour protection instructions taking into account the operational and organisational features of the functioning of the deep-water diving hardware and the diving complex, the features of the vessel on which the complex is installed (a support vessel, a carrier vessel, a floating structure or object, a work site), the diving hardware used, the methods of deep-water diving descents, the nature and types of work performed and the means of their performance; (e) the staffing schedule of the DDC personnel with an assignment to the support stations of the deep-water diving descents; (f) documents on the identification of hazards and the assessment of risks during the preparation and conduct of deep-water diving work, and also on the assessment of the operational readiness and reliability of the deep-water diving hardware.
460. During the planning of and preparation for deep-water diving work, a diving work project and a plan of action in the event of off-normal and emergency situations are drawn up. Deep-water diving work is performed under a permit to work. A daily plan for conducting diving descents shall be drawn up every day. In addition to the requirements for carrying out diving work at shallow and medium depths, the production planning documents for the conduct of deep-water diving work shall include: (a) the duties of the officials and the distribution of duties among them; (b) the schedules for the descent support stations; (c) documents on organising the interaction between the support stations for the period of the deep-water diving work; (d) calculations of the required supply of gases and gas mixtures, and the determination of the procedure for their delivery, transfer and replenishment (where necessary); (e) the determination of the requirement for the range and number of cylinders of control mixtures, on the basis of the depths (pressure values) of the forthcoming descents, the methods of their conduct and the time of the work; (f) process or operational charts for all stages of the diving work with a detailing and a brief description of the divers' work when performing the work (task) on the bottom; (g) documents confirming the technical readiness and the performance of the actions provided for by the system of maintenance and repair of the technical means of performing and supporting deep-water diving work; (h) checklists for preparation for diving descents and for checking the readiness of the descent support stations and of the deep-water diving hardware; (i) a list of exercises for practising the skills of rendering assistance in the event of off-normal and emergency situations. The plan of action in the event of off-normal and emergency situations shall additionally contain actions for the case of emergency evacuation of divers who are in conditions of increased pressure of the (water, gas) medium, when a threat to the safety of the vessel arises. The checklists are drawn up by a specialist who has studied the DDC and has the right to operate and service it, and shall include lists of control questions the answers to which unambiguously indicate compliance or non-compliance with the mandatory requirements that constitute the subject of the check.
461. During deep-water diving descents, audio recording of the communications between the working divers and the diving descent supervisors and video recording of the divers' work shall be ensured. During deep-water diving descents, the diving physician shall keep records in the log of the diving descent.
462. The personnel brought in for deep-water diving descents shall undergo a traineeship directly at the diving complex, and the divers and diving bell operators shall additionally undergo a stage-by-stage mastering of depths. Before each dive, the divers shall undergo a medical examination by the diving physician and obtain permission to descend underwater. Diving specialists admitted to supervising deep-water diving descents shall undergo additional training in the design and operation of the deep-water diving complex and undergo a traineeship as an understudy (trainee) of the supervisor of deep-water diving descents. When deciding questions on admission to supervising deep-water diving descents, the composition of the commission shall include a representative of the organisation that is the manufacturer of the complex and/or a specialist who has mastered that complex and/or has experience of its operation. Diving specialists who have relevant secondary vocational or higher professional education and experience of participation in deep-water diving work are admitted to supervising deep-water diving work.
463. The initial practical training of deep-sea divers, as well as practical training to reach the depth of working descents and during breaks between descents, shall be carried out in accordance with the depth-mastering programme, which is drawn up by a diving specialist and a diving physician. The depth-mastering programme is drawn up taking into account the individual physiological characteristics of the divers and their level of preparedness. The number of divers during deep-water diving descents is determined in accordance with the operating documentation of the deep-water diving complex, depending on the planned scope of the diving work and the chosen method of diving descents, and shall be not fewer than 6 divers. When conducting educational, training and qualification deep-water diving descents in a hydrobaric chamber, the total number of divers under the same pressure shall be not fewer than four, and two divers may work in the water simultaneously. A diver may work alone underwater in a hydrobaric chamber where a standby diver is present in the "dry" part (compartment) of the hydrobaric chamber at readiness No. 1. The degree of readiness of the standby diver is determined by the person in charge of the diving descent. Deep-water diving descents using a diving bell shall be carried out by not fewer than three divers. The first diver is the one working at the site; the second diver is the diver providing support in the water; the third is the operator of the diving bell.
464. To ensure continuous monitoring and control, in addition to the persons in charge of the diving descents and the person in charge of the diving work, a responsible performing authority - a diving specialist - is appointed. When conducting deep-water diving descents, medical support shall be provided directly at the descent site by a diving physician. When carrying out deep-water diving work lasting more than two shifts, there shall be not fewer than two diving specialists and not fewer than two diving physicians, one of whom is appointed as the senior. At least one diving physician shall have health clearance to work in a pressure chamber up to the maximum pressure values during deep-water diving descents.
465. Divers and the personnel of the deep-water diving complex may be assigned a rotational work method, or summarised recording of working time may be applied. The choice of the diving descent method is made by the diving specialist who is the responsible performing authority, taking into account the nature of the work, the depth of the forthcoming descents and their total duration, the type and staffing of the deep-water diving complex, the reserves of breathing gas mixtures and regenerative substances, and the recommendations of the diving physicians, diving specialists and the specialists in the maintenance of the deep-water diving complex. During deep-water diving descents, the work of divers underwater shall be stopped upon detection of a malfunction in the equipment, in the operation of the diving complex, of the descent support systems or of the vessel station-keeping system, and also upon the appearance of complaints of a feeling of overcooling, overheating or fatigue, or other complaints indicating a danger in continuing the work of divers underwater.
466. Preparation for deep-water diving descents shall be carried out using the control and verification sheets: (a) under the direction of the head of the deep-water diving complex or a diving specialist - the technical means of the deep-water diving complex, by the operators of the support stations; (b) under the direction of the person in charge of the diving descent - the working check of the diving equipment and the internal equipment of the diving bell, by the descending divers. After the working check of the equipment, the divers leave in the diving bell the helmet-masks (helmets) and the emergency reserve gas mixture cylinders. The results of the check are recorded in the diving work log. Permission to connect the breathing gas mixtures to the control panels and switchboards, and also to fill the emergency reserve cylinders of the diving bell, is given by the diving physician on the basis of a control analysis of the gas mixtures for their content of oxygen and harmful substances, with an entry in the record of the diving descent. Having received readiness reports from the support stations of the deep-water diving descents, the person in charge of the diving descent of the first shift reports to the responsible performing authority and to the person in charge of the diving work on the readiness of the deep-water diving complex for descents. When conducting deep-water diving descents from a vessel, the person in charge of the diving work informs the master of the vessel of the readiness of the divers to begin the descents. The master of the vessel shall confirm the readiness of the vessel in writing and thereafter gives permission for them to be carried out. When conducting deep-water diving descents from the shore or in other conditions where ensuring the reliability of the mooring or the accuracy of holding the vessel (floating object) at the site of the deep-water diving work does not affect the safety of the deep-water diving work, permission to begin the deep-water diving work is given by the person in charge of the deep-water diving work.
467. The additional safety requirements when carrying out deep-water diving work are: (a) preliminary practising of the organisation for conducting the divers' descents in the chosen mode of use of the complex; (b) a control descent of the diving bell to the forthcoming descent depth; (c) checking the reliability of holding the vessel at the work site or in an area with hydrological characteristics similar to those of the work site; (d) an annual check of the technical condition of the deep-water diving complex, of the means of supporting the diving descents and of the diving equipment, and an audit before the start of the deep-water diving work; (e) presentation of the deep-water diving complex, devices and systems that are under the control of the classification societies; (f) being equipped with the necessary property and materials, instruments and tools, a full supply of gases and gas mixtures, absorbents and regenerative substances, to support the planned diving descents and to carry out (if necessary) therapeutic recompression of the divers; (g) full staffing of the complex with divers, persons in charge of the diving descents, diving physicians, diving specialists and supporting technical personnel; (h) the establishment of requirements for the competence of the personnel taking part in the deep-water diving work, the checking of knowledge and the formalisation of admission to the work; (i) the development of control and verification sheets for all stages and procedures related to the safety of conducting deep-water diving descents; (j) the practising of skills in providing assistance in the event of abnormal and emergency situations.
468. When carrying out deep-water diving work, it shall be prohibited to: (a) use incomplete, faulty items of deep-water equipment and means of supporting diving descents, or those that have not undergone maintenance and repair within the established time limits; (b) begin the performance of deep-water diving descents without prior practical rehearsal by the divers of emergency tasks.
469. When carrying out deep-water diving work, actions shall be provided to prevent the exposure of workers to additional hazardous and harmful production factors, which may include: (a) carrying out maintenance and repair, opening (disassembly) and closing (assembly) of the equipment, systems and devices of the deep-water diving complex and of the diving equipment; (b) checking the conformity of the deep-water diving equipment items, process tooling, instruments and tools used with the design of the specific complex; (c) development of the depth-mastering programme taking into account the individual characteristics of each diver (deep-sea diver); (d) selection of decompression modes; (e) use of gases having documentary confirmation (a certificate or a data sheet) of the contents in each cylinder; (f) preparation of breathing gas mixtures in the required quantity; (g) analysis of the breathing gas mixtures and of the chemical air regeneration means before each descent, and monitoring of their composition before they are supplied for breathing; (h) calibration of the pressure gauges and measuring instruments and checking of the gas monitoring means using calibration mixtures; (i) development of the work and rest schedule of the divers and supporting personnel for the period of conducting the deep-water diving descents; (j) development of the conditions under which deep-water diving descents shall be suspended or prohibited; (k) marking with transponder beacons of the objects in the descent area that may lead to changes in the course of the work, increase the risks of an emergency situation arising, or lead to a reduction in the permissible level of work safety; (l) preparation of a backup launch and recovery device, diving bell and hyperboat; (m) carrying out a full check of the deep-water diving complex before resuming work after a lengthy break in the work or after a suspension of work connected with the occurrence of an abnormal or emergency situation.
470. When performing deep-water diving descents by the method of short-term immersions using apparatus with a closed breathing system (without the use of a deep-water diving complex) for the purposes of production or service activities, the requirements of these Rules shall be complied with. The specific features of conducting deep-water diving descents using apparatus with a closed breathing system (without the use of a deep-water diving complex) shall be taken into account in the local acts of the organisation, the process charts and the production planning documents developed by the organisation carrying out the diving work. The nature of the work performed using apparatus with a closed breathing system (without the use of a deep-water diving complex) and the depth of the descents shall correspond to the intended purpose of the apparatus specified in the data sheet or the operating manual.
471. Specialists who have completed training in the safe methods and techniques of performing work using such devices may be admitted to underwater descents using rigid diving devices, normobaric suits, self-propelled underwater equipment and means of propulsion, manned underwater vehicles, observation and working chambers, and to work in underwater laboratories (hereinafter - the devices). The need for a diving qualification and other types of training and preparation is established in accordance with the requirements of the operating documentation, on the basis of the operating modes and the model of use of the equipment, and also of the need to comply with the applicable regulatory legal acts.
472. To ensure the safe performance of work, a guideline (standard) for carrying out work (or descents) underwater and instructions for the safe operation of the devices, labour protection and the working check before descents shall be developed, taking into account: (a) requirements for the competence of the specialists admitted to operate the devices; (b) the specific features of preparation, operation, servicing, descent and ascent, operating modes and model of use; (c) operating modes and model of use (methods, means, possible places of installation and placement); (d) the types and nature of the work performed using the devices; (e) requirements for the life-support system and the maintenance and repair system; (f) typical hazards, risks, compensating activities and actions in the event of abnormal and emergency situations; (g) additional requirements affecting the safety of work in the devices.
473. The arrangement for conducting descents and performing work in the devices underwater shall provide for the presence of a person in charge of the work and a person in charge of the descents. The time spent by the specialists in the devices shall not exceed the operating time of the life-support systems that ensure favourable conditions for the workers' presence.
474. The list of specific actions to prevent the exposure of workers to hazardous and harmful production factors is determined on the basis of the results of a risk assessment, depending on the conditions and nature of the work using the devices. The specific features of carrying out work using the devices shall be taken into account in the process charts and production planning documents developed by the organisation carrying out the diving work.
475. The direct performance of the medical support activities for diving descents provided for by the Rules is assigned to diving medicine physicians (paramedics) who have undergone special training and have been admitted to the medical support of diving descents.
476. When preparing for diving descents, the employer shall ensure the presence of a medical worker at the site of the diving work in the following cases: (a) diving descents to a depth of more than 45 m; (b) when conducting diving descents, irrespective of their depth, in the following cases: when carrying out rescue and emergency rescue work; when carrying out diving work in mountainous conditions; during educational diving descents; during experimental diving descents; when conducting diving descents by the method of prolonged stay under elevated pressure; on the basis of the results of a risk assessment, where there is a high probability of an accident or emergency occurring.
477. When preparing for diving descents in the absence of a diving medicine physician (paramedic) at the site of the diving work, the employer shall ensure the possibility of calling a diving medicine physician (paramedic) and of his arrival on an emergency basis to the injured diver or the pressure chamber to provide medical care to divers for specific diseases and injuries related to the occupational activity, or the availability of continuous communication with the possibility of recording the conversations of the person in charge of the diving work or the person in charge of the diving descents with the medical worker.
478. In the absence of a diving medicine physician (paramedic) at the site of the diving work, the person in charge of the diving descent shall conduct a survey of the divers' well-being, in which it is necessary to establish: (a) the presence of complaints about well-being; (b) compliance with the work and rest schedule. The results of the survey are entered into the diving work log in the form of entries: "Admitted" or "Not admitted".
479. In the absence of a diving medicine physician (paramedic) at the site of the diving work, upon completion of the diving descent the person in charge of the diving descent shall question the diver about the presence of complaints about well-being and assess the condition of the diver after the descent. If signs of diseases and injuries related to the occupational activity of divers are suspected, detected or recognised in a diver, the person in charge of the diving descents shall: (a) call a diving physician (paramedic) to the site of the diving descents or establish communication with a consulting diving physician and act on his instructions; (b) immediately take measures to provide the diver with all available and planned types of assistance.
480. In the absence of a diving medicine physician (paramedic) at the scene of the incident and where signs of decompression sickness or pulmonary barotrauma are detected, therapeutic recompression may begin before his arrival, after obtaining the recommendations of a diving medicine physician (paramedic) by means of communication. In the absence of a pressure chamber at the descent site, it is necessary to begin evacuation immediately to the nearest pressure chamber that is in a state of readiness. After the arrival of the diving physician (paramedic) at the site of the diving descents, the further provision of assistance, the conduct of therapeutic recompression and its completion shall be carried out under his direction. The fact of the transfer of direction shall be recorded in the diving work log.
481. The arrival time of the medical worker on an emergency basis to provide medical care in cases requiring therapeutic recompression shall be not more than 120 min.
482. When carrying out diving work, at the site of the diving descents the possibility shall be ensured of providing first aid to divers, for diseases and injuries related to the occupational activity of divers, provided by persons without medical education, in the case of injuries and emergency conditions until the arrival of the medical personnel.
483. A diver, in the event of the occurrence of occupational diving diseases, shall receive medical care in full and within the shortest possible time.
484. When carrying out diving work, irrespective of the depth of the descents, the availability of means for breathing medical oxygen shall be provided for. The use of medical oxygen to relieve the symptoms of occupational diseases shall be agreed with the diving physician (paramedic).
485. The recommendations of the medical worker on the medical support of the diving descent shall be binding on the person in charge of the diving work and the person in charge of the diving descent.
486. A diving medicine physician (paramedic), when present at the descent site, is responsible for: (a) conducting the medical examination of divers before diving descents (stay under conditions of elevated pressure of the gas environment); (b) readiness to provide assistance to a diver in the event of the occurrence of diseases and the receipt of injuries related to the occupational activity of divers; (c) the selection of decompression or therapeutic recompression modes and compliance with them; (d) monitoring compliance with the work and rest schedule of divers; (e) compliance with the measures to prevent the occurrence of specific and non-specific diseases; (f) carrying out special sanitary-hygienic and anti-epidemic actions.
487. Divers shall not be permitted to make descents: (a) if there are complaints of poor well-being; (b) if there are objective signs of disease; (c) if there are signs of alcoholic or narcotic intoxication, or of their residual effects; (d) where the systolic (maximum) pressure value is above 140 and below 100 mmHg; (e) where the diastolic (minimum) pressure value is above 90 and below 60 mmHg; (f) where the pulse pressure (the difference between the maximum and minimum pressure) is less than 30 mmHg; (g) where the body temperature is above 37.2 °C; (h) on other objective indications - following the decision of a diving medicine physician (paramedic).
488. First aid and medical care to a diver are provided in accordance with the regulatory legal acts in the field of health protection.
489. Workers may be admitted to the provision of first aid for diseases and injuries related to the occupational activity of divers after special training in the fundamentals of the physiology of human stay under conditions of elevated pressure of the gas and water environment and in diving medicine, with the issue of a document confirming its completion.
490. Training in the provision of first aid for diseases and injuries related to the occupational activity of divers shall be mandatory for all persons in charge of diving descents and diving specialists.
491. The priority actions for providing first aid to an injured diver who is underwater are lifting the diver out of the water and releasing him from the diving equipment.
492. The provision of first aid and medical care for diseases and injuries related to the occupational activity of divers shall be recorded in the form of a report indicating the current time, the changes in the condition of the injured diver and the list of the medical actions performed. The report is kept in the Log of Medical Support of Divers.
493. Therapeutic recompression is carried out by a diving medicine physician (paramedic) or by the person in charge of the descent under the direction of a diving medicine physician (paramedic). Directing therapeutic recompression while under pressure in a pressure chamber shall be prohibited.
494. In the case of a severe condition of the injured diver (with a disease or injury related to the occupational activity of divers and requiring therapeutic recompression), a medical worker who is admitted to stay under conditions of elevated pressure of the gas environment shall be placed in the pressure chamber together with the injured diver.
495. In the absence of a medical worker admitted to stay under conditions of elevated pressure of the gas environment, a diver who is admitted to the provision of first aid for diseases and injuries related to the occupational activity of divers is placed in the pressure chamber.
496. After the completion of therapeutic recompression of the injured diver, he shall be referred to a medical organisation for examination and the establishment of the final diagnosis of the disease and, if necessary, the continuation of treatment.
Validity period of the permit: from "__" _______ 20__ to "__" _______ 20__.
...labour protection requirements have been checked. The safety measures specified in the permit to work have been ensured.
The targeted safety and labour protection briefing was conducted by:
_________________________ _______________ "__" _______ 20__
equipment, tools, appliances, rigging and materials:
protective equipment, safety support systems:
Special conditions for carrying out the work (sources of external hazardous factors):
_________________________ _______________ "__" _______ 20__
Person responsible for labour protection at the site:
___________________________ "__" _______ 20__
___________________________ "__" _______ 20__
The actions to prepare the site for carrying out the work have been completed:
___________________________ "__" _______ 20__
___________________________ "__" _______ 20__
Inclusion of additional personnel in the composition of the diving station (group):
...on industrial safety and labour protection, I understand and guarantee fulfilment:
The violations have been eliminated; I authorise the resumption of the work:
The work has been stopped; the permit to work has been cancelled:
1. Customer ___________________________________________________________________________ (name of the enterprise, address) ___________________________________________________________________________
2. Person in charge of the diving work ___________________________________________________________________________ (position, surname, initials)
3. Person in charge of the diving descents ___________________________________________________________________________ (qualification, surname, initials)
4. Divers ___________________________________________________________________________ (class, surname, initials) ___________________________________________________________________________
5. Medical support is provided by ___________________________________________________________________________ (position, ___________________________________________________________________________ surname, initials)
6. Performance of the work under the assignment: start ___________________________________________________________________________ (date, time) end ___________________________________________________________________________ (date, time)
7. Site, brief description, organisation, sequence of performance and scope of the work ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________
8. To support the work, personnel and technical means are allocated in the quantity of ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________
9. Attached to the work assignment order ___________________________________________________________________________ (list and numbers of the attached diagrams, ___________________________________________________________________________ ___________________________________________________________________________ working drawings of sections) ___________________________________________________________________________
10. During the performance of the work, the safety measures shall be carried out ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ Work assignment order issued by Work assignment order accepted by _________________________ _________________________ (signature) (signature) Agreed: responsible representative of the Customer ___________________________________________________________________________ (position, signature)
11. Note on completion of the assignment ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ Person in charge of the diving work Person in charge of the diving descents _________________________ _________________________ (signature) (signature)
As hazards posing a threat to the life and health of workers engaged in the performance of diving work, the employer, based on the specifics of its production or service activities, may consider any of the following hazards, factors or causes that may lead to their occurrence:
1) hazards associated with the environmental conditions (exposure to elevated pressure of the surrounding environment) in which diving descents are carried out:
(a) elevated pressure of the gas and water environment;
(b) pressure differentials of the gas and water environment and the rate of the differentials;
(c) elevated (and (or) reduced) partial pressure of the principal gases of the breathing mixture (oxygen, nitrogen, carbon dioxide, helium) and of harmful impurities in the breathing gas mixture;
(f) low or high temperature of the air and water;
(h) increased heat capacity and thermal conductivity of the water and compressed gas environment;
2) hazards associated with the conditions of the external surrounding environment:
(a) descents in the dark time of day (at night);
(b) low (high) temperature of the surrounding environment;
(c) exposure of the personnel to extreme natural conditions (including heat, cold, rain, snow);
(d) overcooling and overheating of the diver;
(e) insufficient visibility underwater (absence of visibility);
(f) insufficient visibility at the water surface, at the workplace;
(h) roughness of the water surface, wind speed and current;
(j) dangerous underwater animals and fish in the natural and artificial habitat;
(k) flood tides, ebb tides and currents in the work zone (holding position under high tides and currents);
(m) the nature of the ground (silt, collapses, dangerous ground relief);
(n) operation of hydroacoustic devices in active mode;
(o) operation in active mode of the electrochemical hull protection system of the vessel;
(p) radiation contamination of the water area and the workplace and other contamination (chemical and biological);
(r) increased level of noise or sound pressure;
(s) adverse effects from equipment operating nearby (vibration, turbulence, counterflow);
(t) pressure differential at the water intake gratings and pipes;
(u) exposure to atmospheric pressure differentials before and after immersions (mountainous conditions, flight by air transport);
3) hazards associated with the technology of performing the work and the method of conducting the divers' descents:
- selection, for the diving work, of equipment not corresponding to the nature and type of the work performed and to the conditions of the descents;
- sharp edges of objects at the workplace;
- insufficient illumination of the work zone (the workplace, the descent site);
- increased electrical hazard and electric shock when working with electrical equipment;
- violation of the labour protection requirements established by these Rules, for associated types of work and related occupations;
- incorrect selection of decompression modes;
- static and dynamic physical overload when lifting and moving heavy loads manually;
- increased physical load at the workplace (underwater);
- being caught by an operating unit, rotating equipment or a flow;
- injury when working with ropes, cables and rigging tackle (rupture, impact, destruction, choice of position, tool, sharp ends);
- use of lifting devices and load-handling appliances that have not undergone technical examination;
- displacement of the object or actuation of individual assemblies of the object;
- being under a load being raised (lowered), turning of the load during raising (lowering) without special tag lines;
- loss of the entry opening, loss of orientation;
- explosions and pops from the accumulation of combustion products (gas bubbles);
- discovery of explosive objects or other munitions;
- conduct of ship-wide or marine operations on the deck of the vessel;
- unreliable holding of the vessel at the work site;
- work at a bottom depth horizon exceeding the permissible one;
- the depth limits of operation of the means of supporting diving descents;
- process obstacles on the ground (including cluttering on the ground);
- cramped working conditions, confined enclosed spaces, work inside compartments;
- descents from the workplace at a height of more than 2.0 m;
- vertical or overhead position during welding and cutting;
- the hazard of ground collapse during dredging;
- the hazard of being struck by an underwater blast wave;
- possible work in the zone of secured heavy equipment (in storm conditions);
- pressure differentials in the process equipment, in the water environment;
- the absence of criteria for selecting the organisation carrying out the diving work.
4) hazards associated with the use (failures, malfunctions) of diving equipment and machinery, tools, appliances and process equipment, as well as means of supporting diving descents;
- chemically hazardous substances used in diving practice;
- the isolation of the diver and their remoteness from the attending personnel and from the support facilities;
- the use of faulty gear and equipment;
- the filling of cylinders with high-pressure air (breathing gas mixture);
- failure to observe the time limits for inspections, surveys, repair and maintenance, verification of the control and measuring instruments, and air analysis;
- failure to observe the requirements for storage and upkeep;
- failure to observe the operating rules for equipment and technological processes;
- electric shock: the equipment is not properly insulated, the power source is not disconnected;
- the probability of an interruption of the breathing air supply and other emergency situations independent of the diver;
- destruction of process equipment operating under pressure as a result of emergency situations;
- incorrect selection of gear for the specific environmental conditions and type of work;
- icing of the pressure reducer or the demand valve and other elements of the gear;
- a manufacturing defect (failure of the gear);
- use of apparatus with an insufficient air supply or without a reserve supply;
- lack of monitoring of the organisation of operation and the technical condition of the diving hardware;
- supply of unpurified (contaminated) air for breathing;
- use of uncertified equipment;
- survey of vessels and cylinders;
- non-conformity of the breathing gas mixture used with the conditions of the diving descent;
5) hazards associated with the qualifications of the personnel and the human factor:
(a) high neuropsychic load (fatigue, mental strain, emotional, tension);
(b) lack of the necessary training and instruction of the personnel (lack of knowledge of the hardware, lack of skills in handling the hardware and gear, poor-quality training or lack of training of the personnel);
(c) lack of skills in the techniques and methods for the safe performance of work within the professional activity and in related occupations;
- lack of experience in performing work within the professional functions;
- lack of experience in performing work under specific conditions;
- lack of experience in performing work for the specific type of work;
- personal carelessness, inattentiveness, imprudence, negligence;
- unfitness on grounds of health (absence of a medical board, restrictions on the depth of immersion) unfitness on grounds of well-being before the immersion (fatigue, toxic effects (alcoholic, narcotic, medicinal), mental agitation, illness;
- disruption of the regime of nutrition, work and rest;
- breach of the discipline requirements at the workplace;
- individual predisposition to decompression sickness;
- fear of confined spaces (claustrophobia);
- predisposition of the personnel to seasickness.
1. Ear barotrauma. Occurs in a diver upon a change in the ambient pressure, when a differential is formed between the external pressure and the pressure in the middle ear cavity. The cause of the pressure differential is the impairment or absence of patency of the Eustachian tubes, as a result of which air from the oral cavity does not enter (or enters in an insufficient quantity) the middle ear cavity. Signs. A feeling of "blockage" in the ears with a reduction in hearing acuity. On strong pressure against the eardrums, there may be haemorrhage into the cavity of the inner and middle ear. In individual cases, two to three hours after a sustained ear barotrauma, a diver may experience a sharp deterioration in well-being, accompanied by headache, dizziness, nausea and vomiting. Rupture of the eardrum usually occurs at a pressure differential exceeding 0.2 kgf/cm2 and is accompanied by sharp pain and bleeding from the ear. Prevention. On feeling "pressure on the ears" during the immersion, the diver shall suspend the descent and make several swallowing movements to open the mouths of the Eustachian tubes. If the feeling of "blockage" does not thereby disappear, the depth of immersion shall be reduced by 1 - 2 m and these actions repeated again. If, even in this case, air does not enter the middle ear cavity, the diver shall surface. Dives by divers with a runny nose or with a feeling of "blockage" in the ears shall be prohibited.
2. Barotrauma of the paranasal sinuses (the frontal and maxillary sinuses or the sinuses of the ethmoid bone). Occurs upon obstruction or incomplete patency of the nasal passages associated with a disease of the upper respiratory tract. Signs. Pain in the region of the sinuses, appearing during the immersion or the diver's ascent to the surface as a result of the formation of a difference between the external pressure and the pressure in the paranasal sinuses. Prevention. On the onset of pain, the diver shall suspend the immersion and, if necessary, ascend by 1 - 2 m. If the pain does not pass, the diver is raised to the surface. Dives by divers with a runny nose and painful sensations in the region of the paranasal sinuses shall be prohibited.
3. Pulmonary barotrauma (damage to the lung tissue). The cause of pulmonary barotrauma is a sharp change in the pressure in the lungs, which leads to rupture of the lung tissue and the entry of air bubbles into the circulatory system. Rupture of the lung tissue in divers may occur both upon an increase and upon a decrease in the air pressure inside the lungs, compared with the ambient pressure, by an amount of more than 0.010 - 0.013 MPa. Gas bubbles that have entered the blood vessels are carried by the blood flow throughout the body and may cause blockage of the blood vessels (in particular, the vessels of the brain and the heart), enter the pleural cavity and the tissues of the body. In the event of rupture of the pleura and the formation of a pneumothorax, a significant disturbance of the activity of the cardiovascular and respiratory systems occurs. An increase in pressure only inside the lungs may occur upon breath-holding during a rapid ascent (it is especially dangerous to hold the breath in the last 10 m near the surface, where the expansion of the air occurs relatively more sharply) and upon a spasm of the glottis during a rapid ascent from depth (a spasm of the glottis may occur if cold water enters the respiratory tract or under the dry suit). A decrease in pressure in the breathing system arises in the following cases: ejection of the mouthpiece from the mouth (during a descent in a dry suit with a large-volume helmet) and breathing from the under-helmet space; venting of the breathing mixture through the nose. Pulmonary barotrauma may also occur upon diving to a great depth without gear, where the air of the lungs is not compressed to the value of the ambient pressure, or upon complete exhaustion of the air from the apparatus cylinders, and also upon a malfunction of the demand valve (excessive supply of air on inhalation or high resistance on inhalation) and rupture of the diving hose leading to an interruption of the air supply on inhalation. Pulmonary barotrauma may also occur upon surfacing from under the bell without gear, which is associated, as a rule, with the occurrence of a reflex breath-holding on inhalation upon entering cold water. This circumstance does not allow the diver to exhale during the ascent, which leads to an increase in the intrapulmonary pressure. Signs. Loss of consciousness 1 - 2 minutes after being raised to the surface; bleeding from the mouth or the discharge of frothy sputum coloured with blood; pain behind the sternum; sharp cyanosis of the face, a rapid unstable pulse, shallow breathing with difficult exhalation; in some cases subcutaneous emphysema in the region of the neck and chest; paralyses and pareses of the limbs and other symptoms. Prevention. To prevent pulmonary barotrauma, it is necessary to observe the following rules: - to use controlled methods of raising divers to the surface (diving stages, bells); - to come to the surface along the descent line slowly, and, when swimming, not to allow a sharp change in depth and not to hold the breath. In the event of a forced rapid ascent, with or without apparatus, it is necessary to exhale throughout the entire time of the ascent and on no account to hold the breath. The rate of ascent with the apparatus shall not exceed the rate of the gas bubbles emerging from the valve; - to allow only serviceable and tested apparatus to be used for descents; - to use diving gear with a reserve supply of air (breathing gas mixture), not permitting the use of air supplies (breathing gas mixture) without necessity; - not to allow divers who have a cough to dive; - during descents in regenerative-type gear, not to allow impacts on the breathing bag, both at the surface and underwater; - descents in breathing apparatus having a breathing resistance exceeding the permissible norms shall be prohibited.
4. Decompression (caisson) sickness. Occurs as a result of the formation, in the blood and tissues of the body, of bubbles of an inert gas (nitrogen, helium) upon a rapid decrease in the ambient pressure. The main cause of decompression sickness in divers is failure to observe the regime for reducing the external pressure (incorrect decompression). Signs. In the mild form of the disease: skin itching, rash, change in skin colour (blue-purple spots or "marbling"), pain in the muscles and joints not causing suffering to the patient. In the moderate form of the disease: severe pain in the bones, joints and muscles, a sharp increase in pulse and breathing, sometimes abdominal pain, nausea and vomiting. In the severe form of the disease: damage to the central nervous system (paralyses of the limbs), dizziness, cyanosis, disorder of hearing and vision, loss of consciousness, Ménière's syndrome. Prevention. To prevent decompression sickness, it is necessary: - to observe precisely the established time of the diver's stay on the bottom, and also the rate of ascent to the surface and the time of the holds at the stops; - to take into account, when selecting the decompression regime, the degree of physical load on the bottom, the individual characteristics of the diver and the conditions of the descent (water temperature, current and the nature of the bottom). If the conditions of the descent are unfavourable (heavy work, cold water, strong current, viscous bottom), extended decompression regimes shall be selected.
5. Diver squeeze. May arise in cases where the pressure of the surrounding environment is greater than the pressure of the breathing gas mixture. This occurs in the following cases: - rapid immersion with an insufficient air supply to the diver; - interruption or reduction of the air supply to the diver at depth; - rapid venting of air by the head valve of the ventilated gear; - breaking away and falling of the diver from the descent (under-keel) line. The areas of the body located under the elastic coverings of the gear (the diving shirt) are subjected to the squeeze. Upon a squeeze of the chest, inhalation becomes difficult, the pressure in the helmet decreases and blood rushes to the head and the upper parts of the chest. Signs. Difficult breathing, a rush of blood to the head, bleeding from the nose and ears, discharge of sputum coloured with blood. After coming to the surface, bruises under the eyes and reddening of the sclera of the eye may be noticeable. Prevention. During descents to shallow and medium depths, strictly monitor the supply of the breathing mixture by the pressure gauge. Exercise caution to avoid falling to depth (breaking away from the descent or under-keel line). Do not vent air from the helmet by the head valve if the supply of the breathing mixture from the surface has stopped. Keep a normal quantity of air in the diving suit, venting off its excess. Do not exceed the established rate of immersion. During descents in masks and full-face masks, periodically exhale through the nose into the under-mask space, thereby equalising the pressure under the mask with the surrounding pressure.
6. Oxygen starvation. In a diver working underwater at various depths, oxygen starvation sets in at an equal or lower value of the partial pressure of oxygen than at the surface, and at a considerably lower percentage content of it. When working in regenerative breathing apparatus, the onset of oxygen starvation is possible in cases of incorrect switching into the apparatus without a threefold flushing of the "apparatus - lungs" system with oxygen. The cause of oxygen starvation is a decrease in the content of oxygen in the inhaled air (the blood, flowing through the lungs, is not fully saturated with oxygen). A decrease in the content of oxygen in the inhaled air to 16 per cent (partial pressure 120 mm Hg) does not yet cause any abnormal phenomena in a person. Under such conditions a person may perform light work. If, in the atmospheric air, the content of oxygen becomes lower than 16 per cent, oxygen starvation sets in in the person, the severity of which depends on the value of the partial pressure of oxygen and the severity of the physical work performed. Signs of acute oxygen starvation. Upon a slow decrease in the content of oxygen in the gas mixture, the diver's breathing and pulse become more frequent, a disorder of the movements of the fingers, dizziness, and throbbing in the temples appear, and quick-wittedness and clarity of thought decrease. After some time a feeling of heat throughout the whole body appears, and then loss of consciousness may set in. In the event of a sharp decrease in the partial pressure of oxygen in the inhaled gas mixture, loss of consciousness in the diver during work underwater sets in suddenly, without the appearance of any precursors. On coming to, the affected person, as a rule, does not remember how they lost consciousness.
7. Oxygen poisoning. The toxic effect of oxygen on the human body depends on the value of its partial pressure and on the time of stay in this gaseous environment. When breathing pure oxygen in a chamber under an absolute pressure of 3 kgf/cm2, convulsions and loss of consciousness may set in after 90 minutes. With an increase in the oxygen pressure, the time to the onset of convulsions is reduced. The cause of the onset of oxygen poisoning when carrying out diving work in regenerative gear may be exceeding the permissible depth of descent underwater when breathing pure oxygen and the permissible time of the diver's stay at the given depth. The conditions conducive to the onset of oxygen poisoning in this gear are: accumulation of carbon dioxide in the "apparatus - lungs" system (1 - 2 per cent owing to the low quality of the chemical absorbent or a malfunction of the breathing valves), which accelerates the onset of oxygen poisoning by 4 - 5 times (in which case carbon dioxide poisoning may also set in); strenuous muscular work; overcooling of the body. During descents in ventilated gear and breathing of compressed air, oxygen poisoning may set in only in emergency cases, when the time of the diver's stay at a depth of 50 - 60 m considerably exceeds the permissible time, which may occur only in accidents involving the diver (entanglement, burial by soil during the flushing of tunnels). Signs. The first signs of oxygen poisoning are a feeling of numbness of the fingers and toes, twitching of the muscles of the face (especially the lips) and the eyelids, convulsive twitching of the fingers, a feeling of anxiety. Then general convulsions and loss of consciousness set in fairly quickly. After 1 - 1.5 minutes the convulsions cease, but consciousness does not return. Breathing during this period is frequent and deep. After a further 1 - 2 minutes a second attack of convulsions may set in. If the diver is not raised to the surface, the attacks of convulsions become ever more frequent and longer, and the intervals between them keep decreasing. Upon a rapid increase in the partial pressure of oxygen, attacks of general convulsions with rapid loss of consciousness may set in suddenly, without the appearance of the initial symptoms of poisoning. Prevention. To prevent oxygen poisoning during diving descents, it is necessary: not to exceed the permissible depth when breathing pure oxygen; to know precisely the percentage content of oxygen in the artificial breathing mixtures; not to exceed the permissible (safe) time of stay at depth depending on the partial pressure of oxygen in the breathing mixture; not to exceed the permissible time of stay under increased pressure in the decompression chamber during the breathing of oxygen; not to allow the switching of the diver to the breathing of oxygen at depths of more than 20 m and to maintain precisely the regime of oxygen decompression.
8. Carbon dioxide poisoning. The maintenance of the normal content of carbon dioxide in the body is regulated by the central nervous system and its highest part - the cortex of the brain. The central nervous system is very sensitive to a change in carbon dioxide in the body: upon a decrease or increase in carbon dioxide, breathing, blood circulation and the activity of other systems change, as a result of which the elimination of carbon dioxide from the body decreases or increases. Such regulation is possible up to a certain limit. With a high content of carbon dioxide in the inhaled air, the body cannot cope with the removal of this gas by means of intensified breathing and blood circulation; the activity of individual systems of the body becomes abnormal, and severe disorders and death may set in. During descents in ventilated gear with a breach of the rules for its operation, the content of carbon dioxide in the inhaled gas mixture increases so much that it may lead to poisoning. The causes of the accumulation of carbon dioxide may be: insufficient ventilation of the diving suit or complete interruption of the air supply; insufficient ventilation of the decompression chamber. Signs. Shortness of breath, a feeling of heat, headache, weakness, cold sweat, ringing in the ears, nausea, vomiting. At higher concentrations of carbon dioxide, loss of consciousness sets in, convulsions appear, and breathing and blood circulation stop.
9. Nitrogen narcosis. Nitrogen, which is part of the composition of air, at high pressures possesses a narcotic effect. The depth at which the first signs of the narcotic effect of nitrogen appear depends on the individual sensitivity of the diver: usually this effect begins to appear at depths of more than 40 m. Signs. The signs of the narcotic effect of nitrogen resemble alcoholic intoxication: loss of control over the performed: actions; impairment of orientation and quick-wittedness; unfounded merriment, dizziness; auditory and visual hallucinations; loss of consciousness and deep sleep. Prevention. To prevent nitrogen narcosis, it is necessary to arrange the recording of the working depths reached by divers and of the intervals between descents, and to carry out activities for restoring the training level of divers depending on the interval between descents underwater. When carrying out diving work at depths of more than 30 m, it is necessary to pay particular attention to the intervals between divers' descents to these depths and their individual predisposition and well-being. It is recommended to carry out descents on air to depths of up to 50 m, and, in cases of the need to carry out diving descents in the range of 50 - 60 m, after carrying out activities for restoring the training level of divers for work at the indicated depths.
10. Drowning. Occurs during descents in cases where water enters the respiratory tract and the lungs of the diver. In ventilated or injector-regenerative gear, drowning may occur: upon damage to the upper part of the gear, if the under-helmet air is vented out and water floods the diving suit; upon ejection of the diver from a great depth, when the excess air pressure leads to rupture of the diving shirt. In gear with an open breathing circuit, drowning may occur upon rupture of the membrane of the demand valve or of the inhalation tube. Three types of drowning are distinguished: - white asphyxia (apparent drowning) is characterised by a reflex cessation of breathing and of the work of the heart. The cause may be the entry into the respiratory tract of a small quantity of water, which causes a spasm of the glottis. In white asphyxia a person can sometimes be saved 20 - 30 minutes after drowning; - blue asphyxia (drowning proper) arises as a result of the penetration of water into the alveoli. In this case dilution of the blood and its haemolysis occur, as well as fibrillation of the heart. In such drowned persons the face and especially the auricles, the fingertips and the mucous membrane of the lips are of a violet-blue colour. To revive such an affected person is considerably more difficult and is possible only in the case where their stay underwater lasted no more than 4 - 6 minutes; - drowning in combination with suppression of the functions of the nervous system, which in a diver may set in as a result of cold shock and nitrogen narcosis. Cardiac arrest sets in after 5 - 12 minutes and coincides with the cessation of breathing. This drowning is, as it were, intermediate between white and blue asphyxia. Fibrillation of the heart does not set in, and the dilution and haemolysis of the blood are expressed more weakly than in blue asphyxia. The spasm of the glottis, arising in the initial period of drowning, holds steadily and prevents the entry of water into the alveoli. Usually, in drowning in an unconscious state, water does not enter the lungs. Persons drowned in sea water, as a rule, are easier to revive than persons drowned in fresh water. This is explained by the fact that in drowning in the sea the disturbances caused by a disorder of external breathing predominate, whereas haemolysis and fibrillation of the heart, which extremely complicate drowning, are not observed. However, in the case of drowning in the sea, pulmonary oedema, as a rule, develops in the affected persons after revival. Signs. Cessation of breathing, the presence of water in the respiratory tract and often foam around the mouth and nose, an unconscious state, cyanosis of the skin and the mucous membrane. In severe cases the work of the heart ceases. Prevention. The activities for the prevention of the drowning of divers consist in monitoring the correctness of the working check of the gear, in strict observance of the instructions for the operation of the gear, and in the prevention of cases of immersion underwater in faulty gear.
11. Overcooling. The degree of cooling of the body depends on the water temperature, the duration of the stay underwater, the type of gear in which the diver descends, and the heat-protective properties of the clothing put on by the diver. Signs. Chills, muscular shivering, cyanosis of the skin, stiffening of the muscles. Upon the entry under the suit of a large quantity of cold water (2 - 5 °C), overcooling may develop rapidly as a cold shock with loss of consciousness. Less intensive but prolonged cooling (more than 7 - 8 hours) may also lead to loss of consciousness as a result of a sharp fall in the content of sugar in the blood. Prevention. To prevent overcooling of the diver during descents to shallow and medium depths, it is necessary to monitor the water temperature and to keep track of the duration of the work underwater; to dry thoroughly the clothing and insulating underwear before the descent; to use gear with the possibility of water heating or electrical heating; to cease work upon the appearance of a feeling of chills. To prevent overcooling of divers during deep-water descents, the use of active means of heating the divers is obligatory.
12. Overheating. Overheating of the diver's body may set in during a prolonged wait for the descent after putting on the gear and in the decompression chamber (bell) under conditions of high temperature. Overheating is promoted by heavy physical work, solar radiation, a high temperature of the supplied air, high humidity, and increased pressure. Signs. A feeling of heat, headache, dizziness, general weakness, dryness in the mouth, flickering or darkening in the eyes, nausea and vomiting, reddening and sometimes pallor of the face, an increase in the pulse to 120 beats per minute and in breathing, profuse sweating, a rise in body temperature to 38.5 °C. Prevention. To prevent overheating of divers during the period of dressing and waiting for the descent (especially in southern latitudes), it is necessary to use special awnings to protect divers from direct sunlight and to ventilate the under-suit space: through the flange of the diving shirt, insert a diving hose and supply air through it under a low pressure (1 - 3 kgf/cm2). To prevent overheating of divers working underwater in electrically heated clothing, it is necessary to ensure that the heating power does not exceed the permissible value, and that before entering the bell the electric heating is switched off. To prevent overheating of divers in the decompression chamber, the optimum temperature shall be maintained inside the chamber and in the room where it is installed. To avoid overheating on the surface of divers dressed in dry suits, it is necessary to observe the safely permissible time of stay indicated in the table.
13. Poisoning by harmful (exhaust) gases. Occurs during descents in ventilated gear and gear with exhalation into the water, as a result of contamination of the breathing air with carbon monoxide, nitrogen oxide, saturated and unsaturated hydrocarbons. Contamination of the air may occur upon the entry into the suction pipe of the compressor of exhaust gases or smoke from engines or boiler installations working nearby, and also upon a breach of the operation of the compressor (including overheating, the burning of poor-quality lubricating oil). The danger of poisoning by harmful gases increases with an increase in the partial pressure of the harmful gas, which is proportional to the depth of immersion. Carbon monoxide (carbon monoxide gas) is especially dangerous. Carbon monoxide combines with the haemoglobin of the blood 200 - 300 times faster than oxygen and separates from it very poorly. The breakdown of the compound of haemoglobin with carbon monoxide continues for hours. Haemoglobin bound with carbon monoxide cannot enter into a reaction with oxygen, and the body experiences oxygen starvation. If the atmospheric air at the surface contains 0.05 per cent of carbon monoxide, this threatens health, and at 0.15 per cent severe poisoning sets in. At a depth of 50 m (absolute air pressure 6 kgf/cm2), the partial pressure increases by 6 times, and a content of 0.05 per cent of carbon monoxide in the compressed air becomes fatal, since it corresponds to a content of 0.3 per cent of carbon monoxide in the air at the surface. Signs. Headache, a sensation of compression of the head; a sensation of pulsation in the temporal region ("throbbing in the temples"); darkening and flickering in the eyes; dizziness, vomiting; general muscular weakness, trembling of the limbs. In severe cases of poisoning, mild convulsions and loss of consciousness may set in. Prevention. To prevent poisoning of the diver by harmful gases, it is necessary to take measures excluding contamination of the air supplied to the diver or into the cylinders. For this purpose the suction pipe of the compressor (the pump) is located outside the premises on the windward side in a zone of clean air. It is necessary strictly to monitor the correct operation and the observance of the time limits for the scheduled preventive inspections, cleaning and repair of the air-supply facilities (the compressor, filters, pipelines, cylinders). A new compressor, or a compressor after repair, may be used after analysis of the air for the content of harmful impurities. Analysis of the air of a compressor that is in operation is carried out systematically not less than twice a month. Compressed air in transport cylinders and apparatus shall not be stored for more than one month. The concentrations of harmful impurities in the air supplied to recompression chambers and for the breathing of divers during descents shall be no more than the permissible values.
14. Injury from the air-shock and hydraulic-shock wave during underwater explosions. During underwater explosions, a diver may be subjected to the impact of an air-shock and hydraulic-shock wave, the force of which depends on the magnitude of the charge and the distance of the explosion from the diver. The degree of injury in an explosion underwater is affected by the position of the diver relative to the site of the explosion. More severe injuries occur in cases where the diver is turned to face towards the explosion or is swimming at the surface belly-down. When swimming on the back, the injuries are considerably lighter. Injury from the air-shock wave is possible upon failure to observe the safe distance on the surface of the water. A particular danger is presented by the impact from an explosion inside a compartment (a room, a tank, a pipeline) of gases that have accumulated during work on welding and cutting underwater. Signs. Noise and ringing in the ears; reduction of hearing; sometimes rupture of the eardrums; pain in the region of the chest, headache; nosebleed; general weakness and stunning (indifference to the surrounding situation); rupture of the internal organs. Injuries of the intestine are especially frequent (ruptures, haemorrhage into the wall of the intestine). The prevention of injury by the wave during underwater explosions consists in strict observance of the safe distance from the site of a possible explosion and in the rational choice of position by the diver at the site of work during underwater welding and cutting.
15. Thermal burns. They arise from the direct action on the skin and other tissues of flame, radiant energy, red-hot metals and gases. In diving practice, the cause of burns may be fires in pressure chambers and in rigid diving devices. The causes of a fire in sealed devices (pressure chambers, recompression chambers, rigid diving or deep-water devices) may be an open flame when striking matches or lighters (smoking); the explosion of lighters from the action of elevated pressure; the use of open electric heating appliances; short circuits in the electrical wiring or other faults in the electrical system; and the use of mobile telephones and other electronic devices. The occurrence of fires is promoted by an increase in the oxygen content in the atmosphere of a sealed compartment above 25 per cent. The accumulation of oxygen in pressure chambers is observed during oxygen decompression carried out with the use of regenerative apparatus. The source of oxygen accumulation in rigid diving apparatus is the operation of the air regeneration means. Fires in sealed chambers with a high percentage of oxygen (above 25 per cent) and the presence of an open flame proceed violently, in the manner of an explosion, with a rise in pressure in the compartment. At a high oxygen concentration, smouldering turns into combustion. Once an open flame has appeared, materials that under normal conditions do not burn or burn poorly (rubber products, metal products) may also burn in oxygen. Signs. Intense pain in the affected area. By severity, injuries are divided into four degrees: I - erythema of the skin; II - formation of blisters; III - formation of skin necroses; IV - necrosis of deep-lying tissues. Burns are either limited or extensive, where more than 10 per cent of the skin surface is affected. The prevention of burns from fires in pressure chambers and other sealed devices consists in strict compliance with the rules for their operation (conducting ventilation to prevent a rise in the oxygen concentration in the compartment while divers breathe using regenerative apparatus; prohibiting the use of an open flame in chambers, smoking, electric heating appliances and electronic devices). Before a descent underwater or before entering a pressure chamber, all pocket contents shall be handed over for safekeeping. Before the start and after the completion, pressure chambers shall be inspected to detect within them combustible materials, electronic devices, lighters and other property posing a threat. Persons undergoing decompression in pressure chambers, or placed in sealed devices under conditions of an elevated-pressure (aqueous or gaseous) environment, shall be given a briefing against signature and explanatory work shall be carried out on the dangers associated with being under elevated pressure. Clothing prone to the accumulation of static energy may present a danger.
16. Burns and poisoning by alkalis. Burns are caused by regenerative substances containing alkaline compounds of sodium and potassium when they enter the respiratory tract, the skin and the mucous membranes of the eyes during the sieving of the substance or the charging of apparatus. Poisoning is caused by alkali vapours when they enter the respiratory tract during the reaction of the regenerative substance with water owing to leakage at the joints, a breach of the integrity of the canister, the corrugated tubes or the breathing bag. Signs. The main sign of an alkali burn is a burning sensation of the skin, the mucous membranes of the eyes and the respiratory tract. The signs of poisoning by the vapours of the regenerative substance are: an unpleasant alkaline taste in the mouth, coughing, sharp burning and pain behind the sternum, dilation of the pupils, sharp weakness and generalised convulsions. A feature of alkali burns is that the higher the concentration of the solution, the less pain it causes. Prevention. To prevent burns and poisoning by alkalis when working with the regenerative substance, it is necessary to stand so that the dust of the substance is carried to the side, and it is mandatory to use rubber gloves, protective goggles or a breathing apparatus, and, before a diving descent, to check the regenerative canister thoroughly for tightness to avoid the ingress of water into it.
1. The decompression schedules presented in Tables P1 - P5 are intended for the prevention of decompression sickness in divers during descents underwater, as well as during the training of diving personnel and medical staff in pressure chambers. These schedules are intended for short-term submersions (exposure on the bottom of up to 6 hours).
2. Tables P1 - P5 give: the working decompression schedules for divers during descents to depths of 12 - 60 m using air and oxygen for breathing (Table P1); the working decompression schedules for divers during descents to depths of 12 - 60 m under high-altitude conditions using air and oxygen for breathing (Table P2); the emergency decompression schedules for divers during descents to depths of 15 - 60 m using air for breathing (Table P3); the emergency decompression schedules for divers during descents to depths of 63 - 80 m using air for breathing (Table P4); the decompression schedules for diving personnel and medical staff during training in a pressure chamber using air and oxygen for breathing (Table P5). Oxygen in all schedules may be used only in pressure chambers equipped with fire-extinguishing systems.
3. Purpose of the schedules: - the working decompression schedules of Table P1 are applied during descents by divers from conditions of normal atmospheric pressure; - the working decompression schedules of Table P2 are applied during descents by divers in high-altitude areas from conditions of reduced atmospheric pressure corresponding to altitudes from 1000 to 3000 m above sea level; - the working decompression schedules of Table P2 are applied during descents by divers in high-altitude areas from conditions of reduced atmospheric pressure corresponding to altitudes from 2500 m above sea level; - the emergency decompression schedules of Table P3 are used only in the case of an actual emergency delay of divers at depths of up to 60 m beyond the exposures specified in Tables P1 and P2 (the boundary of high altitude is the 2500 m level); - the emergency decompression schedules of Table P4 are applied only during actual emergency rescue work at depths from 63 to 80 m involving the rescue of people (the supplement to the rules for the use of the emergency decompression schedules presented in Tables P3 and P4 is specified in paragraph 9 of this Appendix). - the decompression schedules of Table P5 are used only during the training of diving personnel and medical staff in a pressure chamber.
4. Each table includes a set of decompression schedules corresponding to various conditions of a diving descent. The content of the decompression schedule tables reflects the depth of the descent, the exposure on the bottom, the time of transition at a uniform rate to the first stop, the depths of the stops and the holding time at each stop, as well as the composition of the breathing mixture (air or oxygen).
5. In all decompression schedules of this Appendix, the exposure on the bottom is calculated from the start of the diver's submersion underwater (the start of the pressure rise in the pressure chamber) to the start of the ascent from the bottom (the start of the pressure reduction in the pressure chamber).
6. If the actual depth of the descent or the time the diver spends on the bottom does not coincide with the depth and time specified in the table, they are rounded up to the greater schedule. The schedules selected in this way are considered the main decompression schedules.
7. The working schedules (of Tables P1 and P2) and the emergency schedules (of Tables P3 and P4) located one row below the main ones are considered extended and are applied during descents of poorly trained divers and divers predisposed to decompression sickness, as well as under unfavourable conditions of a diving descent. Poorly trained divers are considered to be divers undergoing the initial mastering of depths of up to 60 m, as well as those whose previous descent to the depth reached was carried out more than 45 days ago. Divers predisposed to decompression sickness are considered to be divers who have repeatedly suffered decompression sickness after descents carried out in exact compliance with the decompression schedules. Unfavourable conditions of diving descents are a low water temperature (below plus 10 °C at the surface) and the performance of heavy work on the bottom. Decompression of divers at the exposures on the bottom specified in Table P1 below the bold line shall, even under favourable descent conditions, be carried out only according to the extended schedules (located one row below the main schedule). Under unfavourable descent conditions, decompression at the exposures specified in Table P1 below the bold line shall be carried out according to the schedules located two rows below the main schedule. The schedules without a designation of exposure on the bottom, located last in the group of schedules for each submersion depth in Tables P1 and P2, are extended relative to the schedules located one row above.
8. Decompression of divers shall be carried out in exact compliance with the time of transition to the first stop, the depths of the stops and the holding times at the stops. The accuracy of maintaining the depths (pressure) shall be +/- 1 m. The time spent on the diver's transition from stop to stop (1 min) is counted as holding time at the next stop. The exit from the last stop to the surface shall take 1 - 3 min. The decompression schedule is determined separately for each descending diver.
9. Decompression according to the working schedules (Tables P1 and P2) and the emergency schedules for depths of 63 - 80 m with exposures on the bottom of up to 45 - 80 min (Table P4) may be carried out either in full in the water or with decompression at the surface (in a pressure chamber). The use in full of the emergency decompression schedules (Tables P3 and P4) with exposures on the bottom of 6 hours shall be prohibited. These schedules may be used only in combination with therapeutic recompression schedules. Decompression at the surface (Tables P1, P2 and P4) may be carried out starting from the stops marked with an asterisk in the tables, as well as from stops located at shallower depths. For this purpose, after the completion of the hold at the given stop, the diver shall be raised to the surface, freed from the bulky parts of the equipment (the helmet, weights, galoshes), placed in a pressure chamber, and the pressure in it shall be raised to correspond to the depth of the last stop underwater. (The time from the moment of completion of the last hold underwater to the moment of creating the required pressure in the pressure chamber shall be minimal and shall not exceed 6 min.) Under the specified pressure, the diver is held for 10 min (a constant hold), after which decompression is carried out one row lower. Raising the diver to the surface for subsequent decompression in the pressure chamber from stops exceeding the depths marked with an asterisk shall be prohibited. In the case of the use of a decompression schedule with a first-stop depth of 6 m or less (not marked with an asterisk), the diver is raised to the surface from the bottom without a stop. Decompression in the pressure chamber is carried out according to the adopted schedule (without the constant 10-minute hold at the first stop).
10. During decompression according to the working and training schedules in a pressure chamber (Tables P1, P2 and P5), to reduce the decompression time, oxygen decompression may be carried out starting from a depth of 15 - 16 m. The duration of the holds on oxygen in Tables P1 and P2 is indicated in parentheses, and in Table P5 it is designated by the letter "k". In Table P5, the time of breathing air is designated by the letter "v".
11. For breathing oxygen, oxygen masks, inhalers and closed-circuit oxygen apparatus may be used, in compliance with the requirement specified in paragraph 2 of this Appendix. When using closed-circuit apparatus, the time of breathing oxygen is calculated from the moment of completion of the fivefold flushing of the "apparatus-lungs" system. Before the fivefold flushing, an inhalation is made from the breathing bag of the isolating apparatus and an exhalation through the nose into the surrounding environment. Then the cycle of the following actions is repeated five times: an inhalation from the breathing bag and an exhalation into the breathing bag; an inhalation from the breathing bag and an exhalation through the nose into the surrounding environment. The time spent on the fivefold flushing is counted as time of breathing air. The first single flushing is carried out 5 min after the completion of the fivefold flushing. The subsequent single flushings are carried out every 20 min. The use of oxygen shall be prohibited upon the appearance in the diver of the first symptoms of poisoning by this gas (pain behind the sternum, numbness of the tips of the fingers and toes, coughing, narrowing of the fields of vision).
12. If a diver has missed one or two stops during the ascent from the bottom, he shall be lowered as quickly as possible to a stop located 3 m deeper than the first stop specified in the selected decompression schedule. At this stop, the diver is held for 5 min, and further decompression is carried out according to the schedule located one row below the previously selected schedule; the transition to the new schedule (the extension of the schedule) is carried out at this same depth. If a diver has missed more than two stops or has surfaced, having missed all the stops, he shall be quickly transferred to a pressure chamber for carrying out actions for the prevention of decompression disease.
13. When selecting decompression schedules for repeated (within 24 hours) descents to one and the same depth, the exposure on the bottom of the previous descent (descents) is added to the exposure on the bottom of each subsequent descent. Table P1 of this Appendix is used.
14. In the case of a repeated descent within 24 hours to a depth differing from the depth of the previous descent, decompression is carried out according to the schedule for the depth of the last descent and the total exposure on the bottom. The total exposure on the bottom shall not exceed the exposure provided by Table P1 in the maximum decompression schedule for the depth of the last descent located above the bold line.