Order of the Federal Environmental, Industrial and Nuclear Supervision Service (Rostechnadzor) No. 533 of 15 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. These Federal Norms and Rules in the field of industrial safety "General Explosion Safety Rules for Explosion- and Fire-Hazardous Chemical, Petrochemical and Oil Refining Facilities" (hereinafter - the Rules) have been developed in accordance with Federal Law No. 116-FZ of 21 July 1997 "On Industrial Safety of Hazardous Production Facilities" (hereinafter - the Federal Law "On Industrial Safety of Hazardous Production Facilities") (Collection of Legislation of the Russian Federation, 1997, No. 30, Art. 3588; official internet portal of legal information http://pravo.gov.ru, 2020).
2. The Rules establish requirements for ensuring the explosion safety of technological processes, buildings, structures and technical devices used (located) at hazardous production facilities (hereinafter - HPF): (a) chemical, petrochemical and oil-and-gas refining facilities at which the hazardous substances specified in paragraph 1 of Appendix No. 1 to the Federal Law "On Industrial Safety of Hazardous Production Facilities" are obtained, used, processed, formed, stored, transported, destroyed, including where vapour-air, gas-air and dust-air explosion- and fire-hazardous mixtures are formed; (b) oil and oil product storage depots at which the combustible substances specified in sub-clause "c" of paragraph 1 of Appendix No. 1 to the Federal Law "On Industrial Safety of Hazardous Production Facilities" are stored and transported; (c) heat and electric power facilities at which the combustible substances specified in sub-clause "c" of paragraph 1 of Appendix No. 1 to the Federal Law "On Industrial Safety of Hazardous Production Facilities" are stored and transported; (d) trunk pipeline transport (tank farms of the trunk product pipeline, oil pipeline; sites of the loading-and-unloading terminal (racks)) at which the combustible substances specified in sub-clause "c" of paragraph 1 of Appendix No. 1 to the Federal Law "On Industrial Safety of Hazardous Production Facilities" are stored and transported; (e) the oil-and-gas production complex (oil pre-treatment sites; (field) tank farms) at which the hazardous substances specified in sub-clause "c" of paragraph 1 of Appendix No. 1 to the Federal Law "On Industrial Safety of Hazardous Production Facilities" are stored and transported. The provisions of paragraphs 5 to 14 of Chapter II, paragraphs 15 to 41 of Chapter III, paragraphs 62 to 117, 139 to 158 of Chapter IV, paragraphs 181, 201 to 203, 205, 208 to 210, 217 of Chapter V, paragraphs 218, 219, 221, 224, 226 to 228, 230, 232 to 236, 239 to 242, 244, 251, 252, 254 to 271, 274 to 286, 289, 291 of Chapter VI, paragraphs 297 to 300, 302 to 307, 310 of Chapter VII, paragraphs 318, 324 to 327 of Chapter VIII, paragraphs 329, 331, 335 to 340 of Chapter IX, paragraph 342 of Chapter X of these Rules do not apply to the facilities specified in sub-clauses "b", "c", "d" and "e" of paragraph 2 of these Rules.
3. The Rules do not apply to HPF of the mining and metallurgical industry, as well as to HPF of the offshore oil-and-gas complex. The requirements of the second sub-paragraph of paragraph 34 of Chapter III, the first sub-paragraph of paragraph 43 of Chapter IV and the second sub-paragraph of paragraph 344 of Chapter X of these Rules do not apply to HPF put into operation before the entry into force of these Rules, where the design documentation of the HPF (the documentation for the technical re-equipment of the HPF) does not provide for design solutions ensuring compliance with those requirements, until their reconstruction or technical re-equipment in accordance with the design documentation of the HPF (documentation for the technical re-equipment of the HPF) approved in accordance with the established procedure (having undergone an industrial safety expert review with entry of the conclusion into the register of industrial safety expert review conclusions) after the entry into force of these Rules.
4. The Rules are intended for application: (a) in the development of technological processes, the design, construction, operation, reconstruction, technical re-equipment, capital repair, conservation and decommissioning of the HPF specified in paragraph 2 of these Rules; (b) in the manufacture, installation, commissioning, maintenance, diagnostics and repair of the technical devices used at the facilities specified in paragraph 2 of these Rules; (c) in conducting the industrial safety expert review of documentation for the technical re-equipment, conservation and decommissioning of HPF, of the safety justification of HPF, technical devices, buildings and structures, and of the industrial safety declarations of the HPF specified in paragraph 2 of these Rules.
5. The development of a technological process, the division of the production process flow diagram into separate process units, the use of process equipment, the choice of the type of shut-off devices and the locations of their installation, and of the means of monitoring, control and automatic emergency protection (hereinafter - AEP), shall be justified in the design documentation and the documentation for technical re-equipment by the results of the hazard analysis of the technological processes carried out in accordance with Appendix No. 1 to these Rules, using methods for analysing the risk of accidents at the HPF and on the basis of the lowest calculated values of the relative energy potentials QB in the process units forming part of the technological system, in accordance with which the explosion hazard categories of each process unit are established.
6. In the design documentation, an assessment of the energy level of each process unit in which flammable and combustible substances are handled is carried out, and the category of its explosion hazard is determined by calculation in accordance with Appendix No. 2 to these Rules. On the basis of the calculated values of the relative energy potentials QB and the reduced mass of the vapour-gas medium m, the explosion hazard categories of the process units are established (Table No. 1).
On the basis of the explosion hazard categories of the process units, the design documentation gives a justification for the application, effectiveness and reliability of the measures and technical means of emergency protection aimed at ensuring the explosion safety of the given unit and of the entire technological system as a whole.
7. The explosion hazard category of the units, as determined by calculation, shall be taken one level higher if the hazardous substances handled in the process unit are classified as toxic or highly toxic substances in accordance with the requirements of the Federal Law "On Industrial Safety of Hazardous Production Facilities". The increase in the explosion hazard category of the process units, determined by the quantity of toxic and highly toxic substances and by the danger of their causing harm to the operating personnel under probable scenarios for the development of an emergency situation, is justified in the design documentation.
8. Where hazardous substances are present in the process equipment, or where they may be formed, the operating organisation develops the necessary measures to protect personnel from the effects of these substances during explosions and other accidents.
9. Technological processes are conducted in accordance with the process regulations for product manufacture approved by the organisation operating the HPF specified in paragraph 2 of these Rules. The process regulations for the manufacture of products of chemical, petrochemical and oil-and-gas refining facilities are the principal technical document defining the optimal process mode of the process, containing a description of the technological process and of the production process flow diagram, the physico-chemical and explosion- and fire-hazardous properties of the raw materials, intermediate products and finished products, the monitoring and control of the technological process, the safe conditions for operating the production, the list of mandatory production instructions and the drawing of the production process flow diagram (the graphical part). The process regulations for product manufacture are developed on the basis of the design documentation for the HPF. Changes to the process flow diagram, the equipment arrangement, and the monitoring, communication, alarm and AEP systems are made after changes have been made to the design documentation or the documentation for technical re-equipment agreed with the developer of the design documentation or with an organisation specialising in the design of similar facilities, or where there is a positive conclusion of the expert reviews of the design documentation (documentation). The changes made shall not permit any impairment of the operability and safety of the entire technological system.
10. For facilities carrying out activities in the field of the defence-industrial complex, at which explosives and compositions based on them are obtained, used, tested, processed, formed, stored, transported, destroyed (recycled), including pyrotechnic compositions, gunpowders, industrial explosives, rocket fuels and their explosion- and fire-hazardous components, as well as articles containing them, the explosion protection and explosion prevention measures are developed in accordance with the federal norms and rules establishing the basic safety requirements for facilities producing munitions and special chemistry products.
11. For the HPF specified in paragraph 2 of these Rules of hazard classes I, II and III, action plans for the containment and elimination of the consequences of accidents (hereinafter - the APCE) shall be developed and approved in the procedure established by Government Resolution of the Russian Federation No. 1437 of 15 September 2020 "On Approval of the Regulations on the Development of Action Plans for the Containment and Elimination of the Consequences of Accidents at Hazardous Production Facilities" (Collection of Legislation of the Russian Federation, 2020, No. 38, Art. 5904).
12. At facilities that comprise process units of any explosion hazard categories, experimental work to develop new technological processes or their individual stages, to test the lead prototypes of newly developed equipment, and to trial experimental automation means and systems shall be carried out where there is a positive conclusion of the industrial safety expert review of the documentation for the technical re-equipment of the HPF relating to changing the production process flow diagram for carrying out the experimental work, in the event that the specified documentation does not form part of the design documentation of such a facility that is subject to expert review in accordance with the legislation of the Russian Federation on town-planning activities. For carrying out the experimental work, the organisation operating the given HPF also develops and approves technical documentation and an action plan for the safe conduct of the specified work.
13. To acquire practical skills for the safe performance of work, the prevention of accidents and the elimination of their consequences at process facilities with units of explosion hazard categories I and II, all workers and engineering and technical workers directly engaged in conducting the technological process and operating equipment at these facilities undergo a training course using modern technical means for training and developing such skills (computer simulators, training grounds). Computer simulators shall contain dynamic models of processes that are as close to real as possible and real control means (functional keyboards, graphic screen forms). The development of practical skills on computer simulators shall ensure mastery of the technological process and of the control system, of start-up, and of planned and emergency shutdown in typical and specific abnormal situations and accidents. Programmes for developing the skills of start-up, normal functioning, and planned and emergency shutdown of the production (facility) are created on the basis of the process regulations for product manufacture and other process standards and the APCE. The development of the practical skills of workers and engineering and technical workers operating process units of explosion hazard category III is carried out under programmes and technical documentation (the APCE, the process regulations for product manufacture, and the technological instructions for conducting and for the emergency shutdown of technological processes).
14. The organisation of work to maintain a reliable and safe level of operation and repair of the process and auxiliary equipment, pipelines and fittings, monitoring systems, emergency protection, communication and alarm means, power supply, as well as buildings and structures; the distribution of duties and of the boundaries of responsibility among the technical services (the technological, mechanical, power, and instrumentation-and-automation services) for ensuring the requirements of technical safety; as well as the list and scope of the operational, repair and other technical documentation, are determined by the internal administrative documents of the organisation establishing the requirements for the safe conduct of work at the HPF.
15. For each technological system, measures shall be provided for the maximum reduction of the explosion hazard of the process units forming part of it, aimed at: preventing explosions inside the process equipment; protecting the process equipment from destruction and maximally limiting the release from it of combustible substances into the atmosphere in the event of emergency depressurisation; preventing the possibility of explosions and fires within the volume of production buildings, structures and outdoor installations; reducing the severity of the consequences of explosions and fires within the volume of production buildings, structures and outdoor installations.
16. Technological processes are organised in such a way as to preclude the possibility of an explosion in the technological system at the regulated values of their parameters. The regulated values of the parameters determining the explosion hazard of the process, the permissible range of their variation, and the organisation of the conduct of the process (the equipment arrangement and the design of the process apparatuses, the phase state of the substances handled, the hydrodynamic modes) are established in the design assignment by the process developer on the basis of data on the critical values of the parameters or of their combination for the substances participating in the process. The regulated values of the parameters for conducting the technological process are specified in the process regulations for product manufacture as the optimal norms for the safe conduct of the process mode (hereinafter - the regulated process parameters) and shall be subject to monitoring and regulation within the specified range.
17. For each technological process, the set of regulated values of the parameters is determined by the process developer. The permissible range of variation of the parameters is established taking into account the conditions for the safe conduct of the technological process. The technical characteristics of the control system and the AEP shall correspond to the rate of change of the values of the process parameters within the required range (the accuracy class of the instruments, the inertia of the measurement systems, the measurement range).
18. The methods and means precluding the parameters from going beyond the established limits are given in the initial design data, as well as in the design documentation and the process regulations for product manufacture.
19. The conditions for the explosion-safe conduct of a separate technological process or its stages are ensured by: the rational selection of the interacting components, on the basis of the condition of maximally reducing or excluding the possibility of the formation of explosion- and fire-hazardous mixtures or products (established in the initial data); the choice of rational modes of dosing the components, the prevention of the possibility of the deviation of their ratios from the regulated values and of the formation of explosive concentrations in the system (established in the design documentation or the documentation for technical re-equipment); the introduction into the process medium, on the basis of the physico-chemical conditions of the process, of additional substances: inert diluents-phlegmatisers, substances leading to the formation of inert diluents or preventing the formation of explosion- and fire-hazardous mixtures (established in the initial data); the rational choice of the hydrodynamic characteristics of the process (the methods and mode of movement of the medium and mixing of the components, the head and velocity of the flow) and of the heat-exchange characteristics (the thermal head, the heat-transfer coefficient, the heat-exchange surface), as well as of the geometric parameters of the apparatuses (established in the design assignment and the design documentation or the documentation for technical re-equipment); the use of components in a phase state that hinders or precludes the formation of an explosive mixture (established in the design assignment); the choice of the values of the parameters of the state of the process medium (composition, pressure, temperature) that reduce its explosion and fire hazard (established in the design assignment); reliable power supply (established in the design documentation or the documentation for technical re-equipment).
20. The optimal conditions for the explosion safety of the technological system are ensured by: the rational choice of the technological system taking into account the relative energy potentials (QB) of the process units forming part of it, which are determined at the design stage; the division of separate technological operations into a series of processes or stages (the mixing of components in several stages, the division of processes into reaction and mass-transfer processes) or the combination of several processes into one technological operation (a reaction process with a reaction process, a reaction process with a mass-transfer process), permitting a reduction of the level of explosion hazard; the introduction into the technological system of an additional process or stage of purification from impurities capable of forming explosion- and fire-hazardous mixtures or of increasing the degree of hazard of the medium at subsequent stages.
21. For continuous-action technological systems that comprise separate batch-action apparatuses, measures are provided for that ensure the explosion-safe conduct of the regulated operations of disconnecting (connecting) the batch-action apparatuses from (to) the continuous process line, as well as of the operations carried out in them after disconnection.
22. Technological systems (process equipment, pipelines, apparatuses, process lines) in which, upon deviations from the regulated mode of conducting the technological process, the formation of explosive mixtures is possible, are provided with systems for supplying inert gases (inert media) or phlegmatising additives to them, or with other technical means preventing the formation of explosive mixtures or the possibility of their explosion in the presence of an initiation source. The control of the systems for supplying inert gases and phlegmatising additives is carried out remotely (manually or automatically) depending on the features of the conduct of the technological process. For facilities that comprise process units of explosion hazard categories I and II, automatic control of the supply of inert media is provided for; for facilities with process units of category III, the control is remote and non-automatic, and where QB ≤ 10 manual control is permitted.
23. To ensure the explosion safety of the technological system during the start-up or shutdown of process equipment (apparatuses, sections of pipelines), special measures are provided for (including purging with inert gases) that prevent the formation of explosive mixtures in the system. In the design documentation or the documentation for technical re-equipment, the modes and procedure for the start-up and shutdown of process equipment, and the methods for purging it with inert gases that preclude the formation of stagnant zones, are developed taking into account the features of the technological process and are regulated. The monitoring of the effectiveness of the purging is carried out by reference to the content of oxygen and (or) combustible substances in the exhaust gases, taking into account the specific conditions for conducting the purging process, in the automatic mode or by the method of periodic sampling.
24. The quantity of inert gases for each process facility, the system for their transportation and the point of introduction into the technological system are chosen taking into account the features of the operation of the technological system and the simultaneity of loading, and are determined by the design. The parameters of the inert medium are determined on the basis of the condition of ensuring the explosion safety of the technological process.
25. Technological systems shall be equipped with means for monitoring the parameters determining the explosion hazard of the process, with recording of the readings and pre-emergency alarm signalling of their values, as well as with means of automatic regulation and emergency protection, including the AEP. The need to equip technological systems with pre-emergency alarm signalling is determined at the stages of process development and production design. The requirements for the monitoring, control, signalling and AEP systems ensuring the safety of the conduct of technological processes are set out in paragraphs 218 to 252 of Chapter VI of these Rules.
26. For explosion-hazardous technological processes, AEP systems shall be provided for that prevent the occurrence of an accident upon deviation from the maximum permissible values of the process parameters provided for by the process regulations for product manufacture in all operating modes, and that ensure the safe shutdown of the process or its transfer to a safe state according to a predetermined programme.
27. The energy stability of the technological system, taking into account the explosion hazard category of the units forming part of it and the features of the technological process, is ensured by the choice of a rational power supply scheme, by the number of power sources (main and standby) and by their reliability, and shall preclude the possibility of: an impairment of the tightness of the system (depressurisation of the seals of movable joints, destruction of equipment from excess pressure); the formation of an explosive medium in the system (owing to an increase in the residence time of the products in the reaction zone, a disturbance of the ratio of the products entering it, the development of uncontrolled processes). The parameters characterising the energy stability of the technological process, and the means and methods of ensuring this stability, are determined during the development of the initial data and are established in the design documentation and the process regulations for product manufacture. The means of ensuring the energy stability of the technological system shall ensure the capability of the AEP means to function for a time sufficient to preclude a hazardous situation.
28. Technological processes shall not be conducted in the region of explosibility or self-decomposition (chemically unstable substances) of the substances handled in the technological process and of the newly formed products, taking into account the possible formation of by-products, with the exception of reaction technological processes for the conduct of which it is necessary to use unstable substances under conditions of their decomposition (for example, polymerisation processes initiated by peroxide compounds), provided that appropriate measures to ensure explosion safety are developed for them.
29. Technological systems with an explosive medium in which, in accordance with paragraph 28 of these Rules, measures are provided for that exclude the presence of, or prevent the occurrence of, sources of initiation of an explosion inside the equipment, but in which it is completely impossible to exclude hazardous ignition sources (the probability of the appearance of ignition sources remains high), shall be equipped with means of explosion prevention and of protection of the equipment and pipelines from destruction (membrane safety devices, explosion valves, inert-gas phlegmatisation systems, flame-localisation means).
30. Technological systems in which combustible products (gaseous, liquid, solid) capable of forming explosive mixtures with air are handled shall be tight and shall exclude the creation of hazardous concentrations of these substances in the environment in all operating modes. The requirements for sealing, taking into account the hazard factors, are determined by Chapter IV of these Rules.
31. Actions to prevent explosions in equipment are developed taking into account the explosion and fire hazard indicators of the substances handled at the regulated process parameters. When developing actions to prevent explosions and fires in equipment, account shall be taken of the requirements of the technical regulations of the Customs Union "On the Safety of Equipment for Operation in Explosive Media" (hereinafter - TR CU 012/2011), approved by Decision of the Customs Union Commission No. 825 of 18 October 2011 (the official website of the Customs Union Commission http://www.tsouz.ru/, 21 October 2011), which is binding on the Russian Federation in accordance with the Treaty on the Eurasian Economic Union of 29 May 2014, ratified by Federal Law No. 279-FZ of 3 October 2014 "On the Ratification of the Treaty on the Eurasian Economic Union" (Collection of Legislation of the Russian Federation, 2014, No. 40, Art. 5310).
32. For technological systems at the stages associated with the use of solid dusting and disperse substances, measures and means are provided for that maximally reduce the ingress of combustible dust into the atmosphere of the production premises (the working area) and of outdoor installations and its accumulation on equipment and building structures, as well as dust-removal means, the frequency of such removal and the monitoring of the dustiness of the air. Solid disperse combustible substances shall be loaded into the apparatus and processed in the form of granules, solutions, pastes or in a moistened state.
33. For each process unit, taking into account its energy potential, the design organisation develops measures and provides for means aimed at preventing the release of combustible products into the environment or at maximally limiting their quantity, as well as at preventing explosions and preventing injury to the production personnel. The sufficiency of the selected measures and means in each specific case is justified in the design documentation.
34. For facilities that comprise process units of explosion hazard categories I and II, special measures are developed: the placement of process equipment in special explosion-proof structures; the equipping of the production with automated control systems and the AEP ensuring the automatic regulation of the process and the trouble-free shutdown of the production according to special programmes defining the sequence and time of performance of the disconnection operations in emergency situations in the technological system (the process unit, the technical device), as well as the reduction or exclusion of the possibility of erroneous actions of the production personnel during the conduct of the process and the start-up and shutdown of the production.
35. Facilities that comprise process units of explosion hazard category III are equipped with systems of automatic regulation (with or without the use of computer technology), with means of monitoring the parameters the values of which determine the explosion hazard of the process, and with effective fast-acting systems ensuring the bringing of the process parameters to the regulated values or the shutdown of the process.
36. To maximally reduce the release into the environment of combustible and explosion- and fire-hazardous substances in the event of emergency depressurisation of the system, the installation of shut-off and (or) cut-off devices shall be provided for. The locations of the shut-off and (or) cut-off devices are established in the design documentation or the documentation for technical re-equipment. The response time of the shut-off and (or) cut-off devices is determined by calculation, is justified in the design documentation or the documentation for technical re-equipment, and is regulated. In doing so, the conditions for the safe cut-off of the flows shall be ensured, and hydraulic shocks shall be excluded.
37. When designing process flow diagrams for new facilities, account shall be taken, for the emergency emptying of process units of the products handled, of the equipment of the process installations or of special emergency-emptying systems. Special emergency-emptying systems shall be in constant readiness: they shall exclude the formation of explosive mixtures both in the systems themselves and in the atmosphere surrounding them, as well as the development of accidents; they shall ensure the minimum possible emptying time; they shall be equipped with means of monitoring and control. Special emergency-emptying systems shall not be used for other purposes. The capacity of the emergency-emptying system (a special one or in the form of equipment of the process installations intended for the emergency emptying of process units) is calculated for the reception of products in quantities determined by the conditions for the safe shutdown of the technological process.
38. Discharged combustible gases, vapours and finely disperse materials shall be directed into closed systems for further recycling, neutralisation, or into organised combustion systems. For the neutralisation of the discharged media (local systems), various methods are used (thermocatalytic oxidation, adsorption, absorption, chemical complexation, plasma decomposition). The discharge and recycling of non-toxic combustible gases with a density of not more than 0.8 relative to the density of air under the discharge conditions, and of gases containing substances (polymers) capable of clogging flare headers and/or reducing the throughput capacity of the flare header, may be arranged by directing them to a dispersal stack, with justification in the design documentation (documentation for technical re-equipment) of the safety of the technical solution adopted.
39. The combining of gas discharges containing substances capable, when mixed, of forming explosive mixtures or unstable compounds shall not be permitted. When combining the gas lines for the discharge of vapour-gas media from apparatuses with different pressure parameters, measures shall be provided for that prevent the overflow of media from high-pressure apparatuses into low-pressure apparatuses.
40. Where a liquid phase is present in the gas flow, devices that exclude its entrainment shall be provided for on the gas-discharge lines.
41. In processes in which, upon deviation from the specified process modes, the ingress of explosion- and fire-hazardous products into the inert-media supply line (steam, nitrogen and other media) is possible, a check valve is installed on the latter.
42. The limiting values of the velocities, pressures and temperatures of the flammable products conveyed, the main characteristics of the technical devices, the process pipelines and the structural materials used for their manufacture are established in the design documentation (technical re-equipment documentation), taking into account the explosion and fire hazard characteristics and the physico-chemical properties of the substances handled, on the basis of the design assignment. Process pipelines include pipelines intended for conveying, within an industrial enterprise or a group of such enterprises, raw materials, semi-finished products, the finished product and auxiliary materials, including steam, water, air, gases, refrigerants, lubricants and emulsions, and ensuring the conduct of the technological process and the operation of the equipment, and constituting a structure (installation) consisting of pipes, pipeline parts and elements, including pipeline valves, bends, transitions, tees, flanges and elements for the fastening, protection and compensation of the pipeline (supports, hangers, compensators, bolts, washers, gaskets), tightly and firmly joined together.
43. For pumps and compressors (a group of pumps and compressors) conveying flammable products, their remote shut-down and local shut-down and the installation of shut-off or cut-off devices on the suction and discharge lines shall be provided for. The type of valve and the location of its installation on the suction and discharge lines, and the method of its shut-down, including remote shut-down, are justified in the design documentation (technical re-equipment documentation) in each specific case, taking into account the diameter and length of the pipeline and the characteristics of the medium conveyed.
44. When flammable gases and vapours are conveyed through pipelines, measures are provided for that preclude the condensation of the media conveyed or ensure the removal of liquid from the conveying system, and that preclude the crystallisation of flammable products in the pipelines and apparatus.
45. The use of open flame to heat (melt) a crystallised (solidified) product shall be prohibited. Before heating, the section being heated shall first be disconnected from the pressure source(s) and from the adjacent sections of the conveying systems (pipelines, apparatus) technologically connected to it, and other measures shall be taken to preclude the possibility of a dynamic (hydraulic) impact of the heated medium on the adjacent objects (pipelines, apparatus) and their destruction.
46. The compression of flammable gases shall be carried out by centrifugal, reciprocating or screw compressors in accordance with the design documentation (technical re-equipment documentation) and the requirements of the manufacturer's technical documentation.
47. The selection of the design and structural materials and of the sealing devices for pumps and compressors is carried out according to the properties of the medium conveyed. The sealing devices for pumps and compressors shall be manufactured so as to preclude the possibility of the formation of an explosive medium through the leakage of flammable substances through the sealing devices, down to a level ensuring the safe operation of the equipment.
48. For pumps and compressors, the methods and means of monitoring the tightness of the sealing devices and the pressure of the barrier liquid in them are determined. Monitoring of the tightness of the mechanical (end-face) seals of pumps and compressors, of the flanged joints and of the shut-off and control valves installed on their connecting pipelines is ensured through continuous monitoring of the gas contamination of the medium in the working area. If dangerous gas contamination is detected in the premises (compressor rooms, pump rooms), interlock systems shall be provided for to shut down the compressors and pumps and to switch on the emergency ventilation automatically.
49. To ensure the safe operation of the compressor, a separator for separating the liquid phase from the gaseous medium conveyed is installed on the suction line of the compressor. The separator is equipped with level-monitoring instruments, maximum-level alarms and automation means that ensure the removal of liquid from it when the regulated level is reached, and with interlocks that shut down the compressor when the maximum permissible level value is exceeded.
50. The suction lines of compressors shall be under positive (gauge) pressure. In justified cases where these lines operate under vacuum, the oxygen content in the flammable gas shall be monitored; the locations of the sampling points and the monitoring methods are determined by the design organisation; interlocks are provided for that ensure the shut-down of the compressor drive or the supply of inert gas into these lines in the event of the oxygen content in the flammable gas rising above the maximum permissible value.
51. For systems for conveying flammable substances where deposits of the products of resinification, polymerisation and polycondensation may form on the internal surfaces of the pipelines and apparatus, methods and means for cleaning off these deposits are provided for, and the frequency of carrying out this operation is established.
52. In the pipelines of systems for conveying finely dispersed solid flammable substances by pneumatic conveying (the movement of finely dispersed solid substances in a gas stream) or by gravity flow (under the action of gravity), and also in the lines for conveying emulsions and suspensions containing flammable substances, methods for monitoring the movement of the substance conveyed are provided for, and measures are developed to preclude the blockage of the pipelines.
53. Pumps used for the discharge of liquefied flammable gases, highly flammable liquids and flammable liquids shall be equipped with: interlocks that prevent the start-up of the pump or stop its operation in the absence of the liquid conveyed in its casing or where the levels of that liquid in the receiving and delivery vessels deviate from the maximum permissible values; warning alarm means that operate when the parameters in the receiving and delivery vessels reach dangerous values.
54. For submersible pumps, additional interlocking means are provided for that prevent their operation in the event of a current overload of the electric motor, and also their start-up and operation when the supply of inert gas to the apparatus in which these pumps are installed ceases, if the supply of inert gas is necessary under the operating conditions of the pumps.
55. The system for conveying liquefied flammable gases, highly flammable liquids and flammable liquids (hereinafter - LFG, HFL and FL) by means of pumps shall be designed, manufactured and operated taking into account an analysis of operational failures, so as to prevent the possibility of emergency conditions arising. To preclude dangerous deviations of the technological process caused by the stoppage of the pump(s), measures are developed to increase the reliability of the conveying systems, including by installing standby pumps or by arranging supply systems by other methods, for example by the pressure-displacement method.
56. In systems for conveying liquid products in which the formation of local volumes of vapour-gas mixtures is possible, to prevent the possibility of emergency conditions arising, devices are provided for to remove the accumulated gases and vapours into closed systems.
57. The conveying of LFG, HFL and FL by the pressure-displacement method is carried out using inert gases; where appropriately justified in the design documentation (technical re-equipment documentation), the pressure-displacement of liquefied gases is carried out using their own gas phase.
58. The conveying of solid flammable materials shall be carried out by methods that preclude the formation of explosive mixtures inside the equipment and communications. When finely dispersed solid flammable products are conveyed by pneumatic conveying (using air), methods and means are provided for to monitor the concentration of flammable dust in the air stream (by the method of periodic dust sampling, or by the calculation method through the ratio of the measured flow rates of the finely dispersed solid product and the air), and also measures that stop the operation of the pneumatic conveying when the maximum permissible concentration of flammable dust in the air arises. When inert gas is used to convey solid flammable materials, methods and means are provided for to monitor the oxygen content in the system, and also measures that stop the conveying when the maximum permissible oxygen concentration is reached.
59. When finely dispersed flammable materials with the possible formation of explosive mixtures are conveyed, measures preventing the occurrence of an ignition source and measures preventing the propagation of flame in the system are developed and implemented.
60. Systems for conveying finely dispersed solid flammable materials are equipped with interlocks that stop the supply of products into them when the upper limiting level of these materials in the receiving apparatus is reached or when the process of unloading from them ceases.
61. The removal of flammable dust from a surface shall not be carried out using compressed air or another compressed gas, or by other methods leading to the formation of explosive dust-air mixtures above the lower concentration limit of flame propagation and/or to the occurrence of a concentration of harmful substances in the air of the working area above the maximum permissible concentration.
62. Technological processes for the separation of chemical products (flammable products or their mixtures with non-flammable ones) shall be carried out outside the explosibility region (outside the range of concentrations between the lower and upper concentration limits of flame propagation). In doing so, measures preventing the formation of explosive mixtures at all stages of the process are provided for. The degree of separation of the media and the explosion-safety measures are determined during the development of the technological process and are established in the technological regulations for the manufacture of products.
63. When the process for separating flammable vapours (gases) and liquids is designed, means for monitoring and controlling the phase-separation level are provided for, and at the operating stage they are used. The need to use means for the automatic monitoring of the phase-separation level is determined at the stages of process development and production design.
64. Vessel-type apparatus for the separation of flammable, toxic or highly toxic liquid products and non-flammable liquid products shall be equipped with closed drainage systems that preclude the entry into the environment of flammable, toxic and highly toxic vapours.
65. Where a non-flammable liquid subject to discharge into the sewerage system contains dissolved flammable gases, measures for their release and safe removal are developed and implemented. The residual content of dissolved flammable gases in the non-flammable liquid shall be monitored, and the frequency of monitoring and the permissible gas content shall be regulated.
66. Systems for the separation of gas-liquid mixtures shall ensure the effective separation of the phases and prevent the entry of the gas phase into the liquid and the carry-over of liquid with the vapour-gas phase. To ensure a high efficiency of separation of gas-liquid mixtures, the systems are equipped with phase separators.
67. Equipment for the separation of suspensions shall be equipped with interlocks that prevent its start-up and that ensure the shut-down and the stopping of the supply of suspensions in the event of impermissible deviations of the parameters of the inert medium.
68. The development and conduct of the process for separating suspensions in centrifuges shall preclude the formation of explosive mixtures both in the centrifuge itself and in the air of the working area of the premises.
69. For technological processes for the separation of flammable aerosols (gas - solid phase) in filters (electrostatic precipitators) and cyclones, measures ensuring explosion safety during their conduct are provided for, including the automatic monitoring of the vacuum in these apparatus and, where necessary, the automatic monitoring of the oxygen content in the initial aerosol or in the outgoing gas phase, as well as measures to preclude the occurrence of dangerous values of electrostatic field strength.
70. For aerosol-separation apparatus, measures shall be provided for to prevent the formation of solid-phase deposits on the internal surfaces of these apparatus or to remove them (anti-adhesion coatings, mechanical shakers, vibrators, the introduction of additives). The frequency and methods of carrying out operations to remove deposits (dust removal) are regulated by the technological regulations.
71. When developing and conducting mass-transfer processes in which the formation of unstable explosive compounds is possible in the event of deviations of the technological parameters from the regulated values, means for the automatic control of these parameters shall be provided for facilities with process units of explosion hazard categories I and II. For facilities with process units of explosion hazard category III, the performance of control operations in manual mode (by the production personnel) is provided for, subject to the provision of the automatic monitoring of the specified process parameters and of alarms indicating that their permissible values have been exceeded.
72. In apparatus, including distillation columns operating under vacuum, in which substances capable of forming explosive mixtures with atmospheric oxygen are handled, monitoring of the oxygen content in the vapour-gas phase or monitoring of the regulated vacuum values is provided for. The means and methods of monitoring the oxygen content in the vapour-gas phase are determined by the project developer. Where the vacuum in the system falls below the regulated values, the automatic supply of nitrogen into the system shall be provided for, and subsequently the emergency shut-down of the technological process according to a preset programme provided for in the automatic emergency protection (AEP) system and reflected in the technological regulations for the manufacture of products.
73. Distillation columns for flammable liquids shall be equipped with means for monitoring and automatically controlling the level and temperature of the liquid in the bottoms section and the temperature of the product and reflux entering separation, and also with alarm means for dangerous deviations of the parameter values, including the pressure differential between the lower and upper parts of the column, that determine the explosion safety of the process.
74. In cases where a stoppage of the supply of reflux to the distillation column may lead to dangerous deviations of the process parameters, measures ensuring the continuity of the reflux supply are provided for.
75. When carrying out adsorption and desorption processes, measures are provided for to preclude the spontaneous combustion of the absorbent and to equip the adsorbers with means for the automatic monitoring of spontaneous-combustion sites and with devices for extinguishing them.
76. The methods and modes of mixing flammable products and the design of the equipment and mixing devices shall ensure the effective mixing of these products and preclude the possibility of the formation of stagnant zones.
77. For continuous processes of mixing substances whose interaction may lead to the development of uncontrolled exothermic reactions, safe volumetric metering rates of these substances are determined, methods for heat removal are developed, and means for automatic monitoring, process control, emergency protection and alarms are provided for. In batch mixing processes, where the development of self-accelerating exothermic reactions is possible, to preclude their uncontrolled course, the sequence and permissible quantities of the substances charged into the apparatus and the rate of charging (feeding) of the reagents are regulated.
78. In technological processes for mixing flammable products, and also flammable products with oxidisers, the automatic control of the ratio of the components before the mixers is provided for, and for vapour-gas media, pressure control is additionally provided for.
79. Technological apparatus for carrying out the processes of mixing flammable vapour-gas media with an oxidiser shall be equipped with means for monitoring the oxidiser content in the material flows at the outlet of the mixer, or other technological-process parameters that determine the ratio of the components in the system, and also with emergency protection means that stop the supply of components for mixing when the oxidiser concentrations deviate from the regulated values.
80. In process units of explosion hazard category I, the monitoring of the composition of the mixture and the control of the ratio of flammable substances to the oxidiser, and also of the oxidiser content in the material flows after mixing, shall be carried out automatically.
81. The communications leading to the mixers shall be designed so as to ensure the maximum possible level of operational safety with respect to the risk of explosion and shall be equipped with check valves or other devices that preclude (in the event of deviations from the regulated process parameters) the reverse-flow entry into these communications of the flammable substances, oxidisers or mixtures fed for mixing.
82. The grinding and mixing of ground solid flammable products, to preclude the formation of explosive mixtures in the system, shall be carried out in an inert-gas medium. When designing equipment for the grinding and mixing of ground solid flammable substances, the maximum possible level of operational safety with respect to the risk of explosion shall be ensured, and means for supplying inert gas, means for monitoring the pressure of the inert gas supplied, alarms indicating deviation of its pressure from the regulated values and automatic interlocks that prevent the start-up of the equipment without the prior supply of inert gas or that ensure the stoppage of this equipment when the supply of inert gas to it ceases shall be provided for.
83. The organisation of heat exchange and the selection of the heat-transfer medium (refrigerant) and its parameters are carried out taking into account the physico-chemical properties of the product being heated (cooled), so as to ensure the necessary heat transfer and to preclude the possibility of its overheating and decomposition.
84. Heat-exchange processes and heat-exchange equipment shall be designed and selected taking into account an analysis of the possible risks of the formation of explosive substances as a result of the mutual penetration and interaction of the heat-transfer medium with the process medium, so as to prevent the possibility of emergency situations arising.
85. In a heat-exchange process, the use of heat-transfer media that form explosive substances upon chemical interaction with the process medium shall not be permitted. Where such a heat-exchange process is carried out, a process with heat transfer through a wall is selected, and methods and means for monitoring and alarming the mutual penetration of the heat-transfer medium and the process product are provided for, as well as the emergency protection means necessary for the safe conduct of the process.
86. In the case where a decrease in the level of the flammable liquid being heated in the apparatus and the exposure of the heat-exchange surface may lead to overheating, drying out and decomposition of the flammable product and to the development of uncontrolled processes, means for monitoring and controlling the process are provided for, as well as interlocks that stop the supply of the heating agent when the level of the flammable product being heated falls below the permissible value.
87. In surface heat exchangers, the pressure of the non-flammable heat-transfer media (refrigerants) shall exceed the pressure of the flammable substances being heated (cooled). In cases where the pressure of the non-flammable heat-transfer media is equal to or lower than the pressure of the flammable substances being heated (cooled), monitoring for the presence of flammable substances in the non-flammable heat-transfer medium (at the manifold) shall be provided for.
88. In heat-exchange processes, including reaction processes, in which the development of uncontrolled, self-accelerating exothermic reactions is possible in the event of deviations of the technological parameters from the regulated ones, means preventing their development are provided for.
89. In heat-exchange processes during whose conduct the crystallisation of the product or the formation of crystalline hydrates is possible, the introduction of reagents preventing the formation of these products is provided for, and measures ensuring the continuity and reliability of the conduct of the technological processes and their explosion safety are applied.
90. When organising heat-exchange processes with fired heating, measures and means precluding the possibility of the formation of explosive mixtures in the heated elements (coils), the firebox space and the working area of the furnace are provided for.
91. Tubular heating furnaces shall be equipped with: main and duty (pilot) burners fitted with ignition devices and an individual fuel-supply system. Duty burners may be installed in the same housing as the main burners if this is provided for by the burner design (combined block burners); flame-failure detectors that reliably register the presence of flame in the nozzle, or combined block burners with ignition devices that ensure the continuous burning of the nozzle in automatic mode. The number of duty burners and flame-failure detectors and their installation location are justified in the design documentation (technical re-equipment documentation); safety shut-off valves (hereinafter - SSV) or other automatic shut-off devices installed on the gaseous-fuel pipelines to the main and duty burners, in addition to the general cut-off device for the furnace, which operate when the gas pressure falls below the permissible level or upon an emergency shut-down of the furnace. The bringing into operation of these safety devices is carried out only locally, at their installation location, after all the preparatory regulated operations to prepare for the bringing into operation (lighting) of the furnace have been performed (purging of the firebox space of the furnace with steam or inert gas, and of the gaseous-fuel supply lines with inert gas with discharge to the vent stack). The procedure for bringing furnaces into operation (lighting), including after an emergency shut-down, is established in the technological regulations for the manufacture of products and in the start-up instructions.
92. The automatic emergency protection (AEP) of the firebox space of heating furnaces is ensured by: systems for controlling the preset ratio of fuel, air and water steam; interlocks that stop the supply of gaseous fuel and air when their pressure falls below the established parameters (autonomously), and also when the electrical (pneumatic) supply to the instrumentation and automation devices (hereinafter - I&A) ceases; means for signalling the cessation of the supply of fuel, and also of air where it is forcibly supplied into the firebox space; means for monitoring the draught level and for automatically stopping the supply of fuel gas to the combustion zone when the induced-draught fan stops or the vacuum in the furnace decreases impermissibly and, where furnace units are arranged with waste-heat boilers, systems for switching the units over to operation without induced-draught fans; means for the automatic supply of water steam or inert gas into the firebox space and into the coils in the event of tube burn-through, characterised by: a fall in the pressure of the product being heated at the furnace outlet below the regulated value; a rise in temperature above the bridge wall; a change in the oxygen content in the flue gases at the furnace outlet relative to the regulated one. The operating parameters of the interlock for the emergency activation of the supply of steam or inert gas into the coil are determined in the design documentation (technical re-equipment documentation). The automatic emergency protection system shall be provided with emergency parameter alarms and with alarms indicating the operation of the actuating elements. When carrying out catalytic processes used in oil-refining and petrochemical production, the supply of steam into the furnace coils shall not be permitted. The technical solutions for the automatic emergency protection of the firebox space and coils in the event of tube burn-through of heating furnaces are justified in the design documentation (technical re-equipment documentation).
93. The automatic emergency protection of the heated elements (coils) of heating furnaces is ensured by: the emergency release of the furnace coils from the liquid product being heated in the event of damage to the tubes or the cessation of its circulation; interlocks for switching off the supply of fuel to the duty and main burners when the supply of feedstock ceases, when the maximum permissible temperature of the feedstock at the furnace outlet is exceeded, or upon the operation of the flame-failure device; means for the automatic switching-off of the supply of feedstock and fuel in the event of accidents in the coil systems; means for signalling a fall in pressure in the feedstock-supply systems.
94. To isolate furnaces with an open fired process from the explosive medium formed during accidents at outdoor installations or in buildings, the furnaces shall be equipped with a steam curtain or a curtain in the form of a jet supply of inert gases, which is switched on automatically or remotely and ensures the prevention of contact of the explosive medium with the fired space of the furnace. When the curtain is switched on, an alarm shall operate locally and on the operator's panel.
95. Fuel gas for heating furnaces shall comply with the regulated requirements as regards the content of liquid phase, moisture and mechanical impurities in it. To ensure the necessary viscosity and separation from mechanical impurities, liquid fuel shall first pass through a heater and filters before being supplied to the nozzle.
96. When organising heat-exchange processes using high-temperature organic heat-transfer media (hereinafter - HTOH), systems for removing the volatile products formed as a result of their partial decomposition are provided for. When the process is conducted near the upper permissible limit of application of the HTOH, monitoring of changes in the composition of the heat-transfer medium shall be established; the permissible values of the composition indicators of the HTOH are established in the technological regulations for the manufacture of products.
97. The drying agent and the drying modes are selected taking into account the explosion and fire hazard properties of the material being dried and of the heat-transfer medium and the possibility of reducing the explosion hazard of the unit.
98. When carrying out the drying process in an inert-gas atmosphere, the automatic monitoring of the oxygen content in the inert gas at the inlet and/or outlet of the dryer (depending on the features of the process) shall be provided for. In case of a possible exceedance of the permissible oxygen concentration, an automatic interlock for stopping the drying process is provided for, and measures are developed to preclude the possibility of the formation of explosive mixtures in the apparatus.
99. The drying of flammable materials capable of forming explosive mixtures with air shall be carried out in an inert-gas atmosphere. Where there is a justified technical decision to carry out the drying process in a gas-air medium, measures are provided for in the drying units that preclude the reverse-flow entry of the explosive mixture from the dryer into the heating device, and measures for the explosion prevention of the process and the explosion protection of the equipment: fitting with devices that preclude spark formation of frictional (impact, friction) and electrical origin; maintenance of a drying mode that precludes local overheating, the formation of stagnant zones, an increase in the time the material being dried remains in the high-temperature region, and the deposition of product on the walls of the drying chambers; fitting of spray dryers with means for the automatic switching-off of the supply of the material being dried and of the drying agent when the supply of one of them ceases; fitting of drying units with means for the automatic control of the temperature of the material being dried and of the drying agent, as well as with interlocks that preclude the possibility of a temperature rise above the permissible values (switching off the supply of the drying agent, switching on the supply of refrigerant), to prevent thermal destruction and/or ignition of the flammable products; the supply of refrigerant (cold gas, water) automatically when the temperature of the material being dried reaches values above the permissible ones.
100. When carrying out processes for drying flammable substances under vacuum, the supply of inert gas into the working space (purging with inert gas) before the dryer is brought into operation and also upon its stoppage is provided for. The duration of the inert-gas supply is determined taking into account the specific conditions of conducting the technological process and is established in the technological regulations for the manufacture of products. The drying units are equipped with automation systems that preclude the possibility of switching on their heating in the absence of the vacuum in the working space or a decrease in it below the permissible level.
101. Drying installations in which the product being dried is in direct contact with the drying agent shall be equipped with devices for cleaning the spent drying agent of dust from the product being dried and with means for monitoring the cleaning. The cleaning methods and the frequency of monitoring are established in the operating instructions for the drying installations.
102. Technological systems combining several processes (hydrodynamic, heat-and-mass-transfer, reaction) are equipped with instruments for monitoring the regulated parameters. The means of control, regulation and emergency protection shall ensure the stability and explosion safety of the process.
103. The technological apparatus of reaction processes for units of any explosion hazard category is equipped with means for automatic monitoring and control and with protective interlocks for one or a group of parameters that determine the explosion hazard of the process (the quantity and ratio of the incoming initial substances, the content of the components of the material flows whose concentration in the reaction apparatus may reach critical values, the pressure and temperature of the medium, and the quantity, flow rate and parameters of the heat-transfer medium). In doing so, the technological equipment forming part of an installation with process units of explosion hazard category I is equipped with no fewer than two sensors for each hazardous parameter (for dependent parameters, one sensor for each), with means of control and automatic emergency protection and, to ensure the maximum possible level of operational safety with respect to the risk of explosion, with these means and with duplicating control and protection systems.
104. The actuation of the automatic emergency protection systems shall be carried out in accordance with preset programmes (algorithms). When designing the software, the risks of actuation of the automatic emergency protection systems shall be taken into account, and the risks associated with errors in the programme (in the actuation algorithm) shall be excluded.
105. In the control systems for reaction processes in process units with QB ≤ 10, the use of manual control means is permitted, provided that hazardous parameters are automatically monitored and there is an alarm that activates when they exceed the permissible values.
106. When organising and carrying out reaction processes in which the formation of intermediate peroxide compounds, of by-product explosion-hazardous products of resinification and densification (polymerisation, polycondensation) and of other unstable substances is possible, with their probable deposition in the equipment and pipelines, the following are provided for and implemented: monitoring of the content, in the incoming feedstock, of impurities conducive to the formation of explosion-hazardous substances, as well as of the presence, in intermediate products, of unstable compounds and of the maintenance of the specified regime; the introduction of inhibitors that preclude the formation, in the equipment, of hazardous concentrations of unstable substances; compliance with the special requirements placed on the quality of the structural materials used and on the surface finish of the apparatus, pipelines, fittings and instrument sensors that come into contact with the products handled in the process; the continuous circulation of products and feedstock in vessel-type apparatus to prevent or reduce the possibility of deposition of solid explosion-hazardous unstable products; the removal, from the equipment, of the reaction mass enriched with hazardous components; the maintenance of the established regimes and storage times for products capable of polymerising or resinifying, including their transport periods. The choice of the necessary and sufficient conditions for organising the process is determined by the process developer. The methods and frequency of monitoring the content of impurities in the feedstock and of unstable compounds in the reaction mass of intermediate and final products, the procedure for removing the reaction mass containing hazardous by-product substances, and the regimes and storage times of the products are established by the process developer and are reflected in the design documentation (documentation for technical re-equipment) and in the production process regulations.
107. When carrying out reaction processes in which deposits of solid products on the internal surfaces of the equipment and pipelines and the clogging thereof are possible, including of the emergency discharge devices of the process systems, monitoring of the presence of such deposits and measures for their safe removal are provided for and implemented, and, where it is not possible to ensure safe operation by these means, standby equipment is provided.
108. When using catalysts, including organometallic ones, which, upon interaction with atmospheric oxygen and/or water, possess the properties of spontaneous combustion and/or explosive decomposition, measures shall be provided for that preclude the possibility of feeding into the system feedstock, materials and inert gas containing oxygen and/or moisture in quantities exceeding the maximum permissible values. The permissible concentrations of oxygen and moisture and the methods and frequency of monitoring their content in the initial products are determined with account taken of the physico-chemical properties of the catalysts used and of the explosion hazard category of the process unit, and are established in the design assignment and in the production process regulations.
109. The dosing of components in reaction processes shall be monitored automatically and carried out in a sequence that precludes the possibility of the formation, inside the apparatus, of explosion-hazardous mixtures or of an uncontrolled course of the reactions, which is determined by the process developer and established in the production process regulations.
110. To preclude the possibility of overheating of the substances involved in the process, of their auto-ignition or of thermal decomposition with the formation of fire- and explosion-hazardous products, including as a result of contact with the heated elements of the apparatus, the temperature regimes, the optimum rates of movement of the products and the maximum permissible residence time of the products in the high-temperature zone are determined and regulated.
111. To preclude the danger of the occurrence and development of accidents, including as a result of an uncontrolled development of the process, measures for the stabilisation of reaction processes and for the emergency emptying of the apparatus, and methods for eliminating possible emergency situations, shall be provided for. The measures and methods for eliminating possible emergency situations set out in the production process regulations shall correspond to, and be combined with, the actions for the localisation and elimination of accidents provided for by the PMLA.
112. The use of the residual pressure of the medium in a batch reactor to force the reaction mass over into another apparatus is carried out only where this decision is justified in the design documentation (documentation for technical re-equipment), taking into account an analysis of operational failures, so as to prevent the possibility of the occurrence of emergency situations.
113. Apparatus for conducting liquid-phase processes shall be equipped with systems for monitoring and controlling the liquid level therein and/or with means for automatically shutting off the supply of this liquid to the apparatus when the specified level is exceeded, or with means that preclude the possibility of overflow.
114. Reaction apparatus of explosion-hazardous processes fitted with agitating devices are equipped with means for the automatic monitoring of the reliable operation and tightness of the seals of the agitator shafts, as well as with interlocks that prevent the possibility of loading products into the apparatus while the agitating devices are not operating, in those cases where such loading is not provided for by the design and by the manufacturer's technical documentation for the technical device.
115. Reaction apparatus in which the removal of excess reaction heat by heat transfer through the wall is carried out by evaporation of the cooling liquid (refrigerant) shall be equipped with means for the automatic monitoring, control and signalling of the refrigerant level in the heat-exchange elements.
116. In systems for cooling reaction apparatus by liquefied gases, where the temperature of the refrigerant (the boiling temperature of the liquefied gas) is ensured by maintaining the equilibrium pressure, the value of the pressure of the liquefied gas shall be maintained (controlled) automatically; the possibility of the pressure rising above the permissible value in the event of a sudden shutdown of the refrigeration units in the cooling system (a sudden shutdown of the cooling system) shall be precluded; and measures shall also be provided for that automatically ensure the emptying (discharge) of the refrigerant from the heat-exchange elements of the reaction apparatus.
117. The development and conduct of reaction processes involving the production or use of products characterised by high explosion hazard (acetylene, ethylene at high parameters, peroxide and organometallic compounds) that are prone to thermal decomposition or to spontaneous self-polymerisation and self-heating, and that are also capable of auto-igniting or exploding upon interaction with water, atmospheric oxygen or with one another, shall be carried out with account taken of these properties and shall provide for safety measures. Additional special safety measures are set out in the design assignment, in the design documentation (documentation for technical re-equipment) and in the production process regulations (and are established by the process and design developer).
118. The arrangement and siting of warehouses, and also of loading and unloading racks and of tanks (vessels) for the storage and pumping of SGG, LVZh and GZh, shall comply with the requirements of the legislation of the Russian Federation on town-planning activities, of the design documentation (documentation for technical re-equipment) and of these Rules.
119. The procedure for performing the process operations for the storage and movement of combustible liquid substances (SGG, LVZh and GZh) and for the filling and emptying of mobile and stationary storage tanks, and the selection of the process parameters that determine the explosion safety of these operations (pressure, rates of movement, maximum and minimum permissible levels, methods of relieving the vacuum), shall be carried out with account taken of the physico-chemical properties of the combustible substances and shall be regulated.
120. Storage tanks (vessels) and loading and unloading racks for SGG, LVZh and GZh shall be equipped with means for monitoring and controlling the hazardous process parameters specified in paragraph 119 of these Rules.
121. When storing SGG, LVZh and GZh and carrying out loading and unloading operations, stationary and mobile tanks (vessels) and loading and unloading devices shall be used only for those products for which they are intended. In doing so, to prevent an impermissible change in the physico-chemical characteristics of the substances, including those reflecting their fire, explosion and toxic properties, measures are developed and implemented that preclude the possibility of accidental mixing of products at all stages of the loading and unloading operations. Where justified in the technical documentation (process regulations and instructions), the filling of empty, specially prepared vessels with other products similar in their physico-chemical characteristics and storage indicators to those liquid combustible products for which they are intended is permitted. In such cases, the possibility of exceeding the pressures permissible for the vessel shall be precluded. The procedure for preparing the vessels for filling (freeing them from residues of the products previously contained in them, flushing, cleaning and neutralisation of the vessels) and the performance of work to switch over (connect) pipelines and fittings are specified in the technical documentation.
122. When storing and carrying out loading and unloading operations with substances capable, under storage conditions, of forming by-product chemically unstable compounds (substances) and of accumulating impurities that increase the explosion hazard of the main product, the design documentation (documentation for technical re-equipment), the production process regulations and the instructions shall provide for measures that preclude the possibility of, or reduce the rate of, the formation and accumulation of impurities and by-product chemical compounds, as well as for monitoring of their content in pipelines, stationary and mobile tanks and other equipment, and for methods for their timely removal.
123. When preparing stationary and/or mobile tanks for filling with SGG and LVZh after installation, repair, cleaning and the performance of similar work, measures shall be provided for that preclude the possibility of an explosion in this equipment. The procedure for preparing for filling and the monitoring of the oxygen concentration in the equipment and of other parameters that determine the explosion hazard are specified in the technical documentation.
124. The capacity of tanks (vessels) for SGG stored under pressure is established with account taken of the energy indicators of the explosion hazard and of the specific conditions, including account taken of the danger of the occurrence of damaging factors in a possible accident involving destruction of the tank and the formation of a "fireball".
125. The design of tanks with floating roofs (pontoons), the procedure for carrying out operations for their filling and emptying, and the product withdrawal system shall preclude local overheating and spark formation caused by the friction of moving parts and their possible impacts, and, in the event of malfunctions of the roofs (pontoons), shall prevent their destruction and possible explosions in the tanks.
126. Tank cars intended for the carriage of SGG, LVZh and GZh by rail shall be equipped with fittings, monitoring means and loading and unloading, protective and other devices, with account taken of the physico-chemical properties of the products carried and of the safety requirements for the carriage of dangerous goods by rail transport.
127. The procedure for placing (spotting) railway tank cars for the loading and unloading of combustible products shall ensure the safe conduct of these operations. During the loading and unloading of railway tank cars, measures shall be provided for and implemented that prevent the possibility of spontaneous movement of the tank cars undergoing loading and unloading, of depressurisation of the loading and unloading devices and of the release of combustible products into the atmosphere, and that also preclude the presence of permanent or accidental ignition sources (of mechanical, electrical or other origin) in the zone of possible gas contamination.
128. It shall not be permitted to use railway tank cars containing SGG, LVZh and GZh that are located on railway tracks as stationary, storage (service) vessels.
129. The discharge of SGG, LVZh and GZh from tank cars and their filling into them shall be carried out at loading and unloading racks. For each type of product to be loaded, where its mixing with other products is impermissible, separate loading and unloading racks or separate discharge and/or filling devices at these racks are provided for. It shall not be permitted to use filling devices for the alternating filling of products that are incompatible with one another.
130. At loading and unloading racks, specially equipped places shall be provided for carrying out the emergency emptying of faulty tank cars. The safety measures for the performance of these operations shall be established in the design documentation (documentation for technical re-equipment) and in the instructions.
131. The tank cars, tanks, pipelines and technical devices of the loading and unloading systems for SGG, LVZh and GZh shall ensure the safety of servicing and operation. The arrangement of the loading and unloading systems for SGG, LVZh and GZh shall preclude the possibility of spills and of the entry into the atmosphere of combustible vapours and gases that is not provided for (by the design documentation and the manufacturer's technical documentation for the given device) during loading and unloading operations.
132. In systems intended for the loading and unloading of various liquid substances, the use of devices made from materials that are not resistant to the media being pumped shall not be permitted.
133. Loading and unloading racks for SGG, LVZh and GZh shall be equipped with reliable automatic devices that preclude the overfilling of tank cars.
134. Loading and unloading racks intended for the filling of SGG, LVZh and GZh by pumps shall be equipped with means for their remote shutdown. The shutdown devices shall be located in easily accessible places that are convenient for operation and servicing and are selected with account taken of the safety requirements.
135. On the pipelines through which SGG, LVZh and GZh enter the rack, fast-acting shut-off devices or gate valves with remote control shall be installed to shut off these pipelines in the event of an accident at the rack. The control of these devices shall be both local and remote (from a safe place).
136. For the safe conduct of operations for the filling (discharge) of liquefied gases and low-boiling combustible liquids (with a boiling temperature below the ambient temperature) into (from) tank cars, measures shall be provided for that preclude the possibility of vapour formation in the pipelines, of cavitation, of water hammer and of other phenomena capable of leading to the mechanical destruction of the elements of the loading and unloading system.
137. When designing loading and unloading racks for SGG, LVZh and GZh, measures for protection against atmospheric and static electricity shall be provided for, and, during loading and unloading operations, such measures shall be implemented.
138. At loading and unloading racks, the possibility of connecting the loading and unloading system to installations for the organised collection and utilisation of the vapour-gas phase, where it is necessary to empty the system of these products, shall be ensured. To preclude the formation of explosion-hazardous mixtures in the systems of pipelines and collectors for loading and unloading, the supply of inert gas and steam to them, as well as the possibility of the complete and reliable removal of combustible substances from these systems, shall be provided for.
139. Discharges of combustible gases and vapours, which are divided into continuous, periodic and emergency discharges, shall be directed, for combustion or for collection and subsequent use, to flare systems: a common one (provided that the discharges are compatible); a separate one; a special one.
140. The type and design of the flare system, the design and type of the flare tip, and also the fuel gas flow rates and the signalling solutions, are selected by the design organisation depending on the operating conditions of the flare system, the arrangement of the discharges, and the properties and composition of the gases discharged, and are justified in the design documentation (documentation for technical re-equipment).
141. Where gases, vapours and mixtures thereof that do not cause corrosion of more than 0.1 millimetre per year are discharged into the common flare system, it is permitted to provide the flare installations with a single collector, subject to technical justification in the design documentation (documentation for technical re-equipment).
142. The monitoring of the operation of flare systems and their remote control shall be carried out: for a common flare system - from a central control room, a dedicated control room or the control room of one of the nearby process plants discharging gas into the flare system; for separate and special flare systems - from the control room of one of the process plants discharging gas into the flare system.
143. Flare systems shall be equipped with technical means that ensure the continuous recording (with the readings displayed in the control room) of the following data: the flow rate of the purge gas into the flare collector or gas seal; the liquid level in the separators and condensate collectors; the liquid level in the flare liquid seal; the temperature of the gases and vapours entering the gas holder (where justified in the design documentation (documentation for technical re-equipment)).
144. Flare systems shall be equipped with alarm means (with the signals displayed in the control room) that activate when the following parameters are reached: the minimum permissible flow rate of the purge gas in the collector or gas seal; the minimum permissible pressure or flow rate of the fuel gas to the pilot burners; the extinguishing of the flame of the pilot burners; the maximum permissible liquid level in the separators and condensate collectors; the minimum permissible liquid level in the flare liquid seals; the maximum permissible temperature of the gases entering the gas holder; the presence of combustible gases and vapours in an amount of 20 per cent of the lower concentration limit of flame propagation (hereinafter - NKPR) in the premises of the compressor room and of the liquid seal, with duplication of the audible and light signals and with these alarm means located above the entrance door, and also at outdoor installations at the places where the gas holders, separators and pumps are located. Means for signalling rarefaction are not required if the product of the difference between the densities of the air (kilograms per cubic metre) and the purge gas and the height of the flare stack (metres) does not exceed 100.
145. The design of the flare installation shall provide for automatic control of the pressure of the fuel gas supplied to the pilot burners and of the flow rate of the purge gas supplied to the beginning of the flare collector.
146. Flare systems shall be equipped with interlocks that ensure: the opening of the remotely controlled shut-off fittings on the line for discharging gases into the flare installation when the gas holder is filled to 85 per cent of its total volume, with the simultaneous closing of the remotely controlled shut-off fittings on the line for the entry of gas into the gas holder; the opening of the remotely controlled shut-off fittings on the line for the entry of gas into the gas holder when it is filled to 70 per cent of its total volume, with the subsequent closing of the remotely controlled shut-off fittings on the line for discharging gases and vapours into the flare stack.
147. Before each start-up, the flare system shall be purged with steam or nitrogen (inert gas) into the atmosphere to displace the air down to the oxygen content determined in the design documentation of the hazardous production facility (the documentation for technical re-equipment of the hazardous production facility) and specified in the production process regulations, provided that the flare system (a separate or special one) forms part of the process plant, or in the general operating instruction for the flare system.
148. The flare installation shall be provided with devices for remote ignition and for continuous remote monitoring of the presence of the flame.
149. During the operation of the flare pipelines, the possibility of the entry of air into them and of the formation of explosion-hazardous mixtures, as well as the possibility of their blockage by ice plugs, shall be precluded; the continuous supply of purge gas to the flare system shall be ensured (unless the process provides for constant discharges in a sufficient volume); and the timely emptying of the technical devices for trapping and collecting condensate shall also be ensured in accordance with the design solutions.
150. When discharging gases and vapours, including those of a complex composition, the possibility of the formation of an explosion-hazardous mixture of any component with oxygen shall be precluded.
151. To prevent the formation of an explosion-hazardous mixture in the flare system, the automatic continuous supply, to the beginning of the flare collector, of purge gas (fuel gas, natural gas or nitrogen (inert gas), including those obtained at the process plants and used as inert gases) shall be provided for.
152. When supplying to the flare system, for combustion, combustible gases and vapours containing inert gases (during the preparation of equipment for repair), which may lead to the extinguishing of the flare, additional safety measures shall be provided for, such as visual monitoring of the burning of the flare, an increase in the supply of natural gas to the beginning of the flare collector, and a limitation of the rate of discharge of the mixture of combustible and inert gases.
153. The directing into the flare system of substances whose interaction may lead to an explosion (an oxidiser and a reducing agent) shall not be permitted. Discharges containing more than 1 per cent of toxic and highly toxic substances (except benzene) or more than 8 per cent of hydrogen sulphide shall be directed to a separate or special flare system. The arrangement and operating conditions of special flare systems are justified in the design documentation (documentation for technical re-equipment).
154. The reliability of the power supply of the control, monitoring and automation system of flare systems is justified in the design documentation (documentation for technical re-equipment).
155. Before carrying out repair work, the flare system shall be disconnected from the process systems by standard blanks and purged with nitrogen (inert gas) in accordance with the requirements of the instruction on the procedure for the safe performance of repair work approved by the operating organisation.
156. Within the territory of the production site, the flare installation shall be located with account taken of the wind rose. The length of the flare collectors (pipelines) shall be minimal. The height of the flare stack of the flare installation is determined by calculation of the heat flux density in the design documentation (documentation for technical re-equipment).
157. The territory around the flare stack, except in cases where it is located within the territory of a process plant, is fenced and marked with warning signs. In the fencing, a passage for personnel and gates for the passage of vehicles shall be provided for.
158. When the flare system is shut down, obstruction lighting of the upper points of the flare stack shall be provided for in accordance with the requirements for the marking and obstruction lighting of tall obstacles.
160. The selection of equipment shall be carried out in accordance with the design assignment, the requirements of the regulatory legal acts in the field of industrial safety and of these Rules, and with account taken of the explosion hazard category of the process units.
161. For process equipment and pipeline fittings, an assigned service life is established with account taken of the specific operating conditions. Data on the service life shall be indicated by the manufacturer in the data sheets of the equipment and pipeline fittings in accordance with the requirements of the Technical Regulation of the Customs Union "On the Safety of Machinery and Equipment" (hereinafter - TR CU 010/2011), adopted by decision of the Customs Union Commission No. 823 of 18 October 2011 (official website of the Customs Union Commission http://www.tsouz.ru/, 21 October 2011), which is mandatory for the Russian Federation in accordance with the Treaty on the Eurasian Economic Union of 29 May 2014, ratified by Federal Law No. 279-FZ of 3 October 2014 "On the Ratification of the Treaty on the Eurasian Economic Union" (Collection of Legislation of the Russian Federation, 2014, No. 40, Art. 5310). For process pipelines, a design operating life is established by the design organisation, which shall be reflected in the design documentation (documentation for technical re-equipment) and entered into the data sheet of the pipelines. Upon expiry of the service life or upon exceeding the number of load cycles of the process equipment, pipeline fittings and process pipelines established by the manufacturer, such process equipment, pipeline fittings and process pipelines shall be subject to an industrial safety expert examination in accordance with the requirements of Articles 7 and 13 of the Federal Law "On Industrial Safety of Hazardous Production Facilities".
162. For equipment (apparatus and pipelines) where it is impossible to preclude the formation of explosion-hazardous media and the occurrence of energy sources whose magnitude exceeds the minimum ignition energy of the substances handled in the process, methods and means for explosion protection and flame localisation are provided for and, in justified cases, an increase in the mechanical strength calculated for the full explosion pressure. The effectiveness and reliability of the means of explosion protection, flame localisation and other emergency protection devices shall be confirmed by their manufacturer before the start of their use at the hazardous production facility by means of tests of industrial samples of the equipment for explosion resistance.
163. The provision of equipment with emergency protection devices does not eliminate the need to develop measures aimed at preventing the formation of ignition sources in it.
164. It shall not be permitted to use, for the manufacture of equipment and pipelines, materials which, upon interaction with the working medium, may form unstable compounds that are initiators of the explosion of the products being processed.
165. The manufacturing quality of the process equipment and of the pipelines for it provided for by the engineering documentation shall comply with the requirements of TR CU 010/2011 and TR CU 012/2011. The arrangement of apparatus operating under excess pressure shall comply with the requirements of the Technical Regulation of the Customs Union "On the Safety of Equipment Operating under Excess Pressure" (hereinafter - TR CU 032/2013), adopted by decision of the Customs Union Commission No. 41 of 2 July 2013 (official website of the Eurasian Economic Commission http://www.eurasiancommission.org/, 3 July 2013), which is mandatory for the Russian Federation in accordance with the Treaty on the Eurasian Economic Union of 29 May 2014, ratified by Federal Law No. 279-FZ of 3 October 2014 "On the Ratification of the Treaty on the Eurasian Economic Union" (Collection of Legislation of the Russian Federation, 2014, No. 40, Art. 5310), and of the regulatory legal acts in the field of industrial safety and of these Rules.
166. The installation of process equipment and pipelines shall be carried out in accordance with the design and working documentation. Equipment and pipelines, materials and component products may not be allowed for installation in the absence of documents confirming the quality of their manufacture.
167. In the data sheets of the equipment, pipeline fittings, monitoring instruments and automation means, the reliability indicators provided for by TR CU 010/2011, TR CU 012/2011 and TR CU 032/2013 shall be indicated.
168. At plants with process units of explosion hazard category I, the welded joints of category I process pipelines that transport fire- and explosion-hazardous and toxic or highly toxic substances shall be subject to 100 per cent inspection by non-destructive methods (ultrasonic flaw detection, penetrating-radiation inspection or other equivalent methods). The selection of the non-destructive testing methods and the scope of testing of other categories of pipelines shall be determined by the design documentation (documentation for technical re-equipment) and by the federal norms and rules in the field of industrial safety that establish the requirements for non-destructive testing of technical devices, buildings and structures at hazardous production facilities, and shall be sufficient to ensure their safe operation.
169. Process systems shall be leak-tight. In the design documentation (documentation for technical re-equipment), the use of equipment is justified for which, in accordance with the manufacturer's technical documentation, the limits of possible regulated leaks of combustible substances are specified (with an indication of the permissible values of these leaks under operating conditions). In the design documentation (documentation for technical re-equipment), the procedure for their collection and removal shall be defined.
170. For the sealing of movable joints that are under the pressure or rarefaction of the working medium, and of rotating shafts of process equipment that are located in (in contact with) LVZh and SGG, end-face-type seals shall be used.
171. When arranging the external thermal insulation of process apparatus and pipelines, measures for protection against the ingress of combustible products into it shall be provided for. The temperature of the external surfaces of the equipment and/or of the casings of the thermal-insulation coatings shall not exceed the auto-ignition temperature of the most fire- and explosion-hazardous substance and, in places accessible to the operating personnel, shall be no more than 45 degrees Celsius indoors and 60 degrees Celsius at outdoor installations.
172. The design of the heat exchange devices of process equipment shall preclude the possibility of mutual penetration of the heat transfer medium and the process medium. When designing process equipment with heat exchange devices, their conformity with the requirements of TR CU 012/2011 shall be ensured. The procedure for testing and for monitoring the condition and operation of the heat exchange devices is determined by the manufacturer's technical documentation.
173. For apparatus with gas-phase processes and for gas pipelines in which, under the conditions of the process, partial condensation of vapours occurs, devices for the collection and removal of the liquid phase shall be provided. Where it is impossible or unnecessary to install a device for the collection and removal of the liquid phase, the decisions taken shall be justified in the design documentation (documentation for technical re-equipment).
174. For carrying out the periodic equipment-cleaning work established by the regulations, means of hydraulic, mechanical or chemical cleaning are provided which exclude the presence of persons inside the equipment (with the exception of individual operations specified in the second sub-paragraph of this paragraph). When performing individual operations to clean process equipment, the presence of persons inside the equipment may be permitted where such operations cannot be mechanised, automated or carried out without the direct participation of persons.
175. Apparatus containing explosion and fire hazardous substances shall be equipped with devices for connecting water, steam and inert gas lines. When designing this type of equipment, devices for purging the apparatus shall be provided.
176. For explosion and fire hazardous process systems whose equipment and pipelines are subject to vibration during operation owing to the nature of the work, measures and means shall be provided to exclude its effect on the sealing elements and to reduce the effect on adjacent elements of the process system and on building structures. The limit levels of vibration for individual types of equipment and its elements (assemblies and parts), the methods and means of monitoring these values and the ways of reducing them shall be reflected in the technical documentation for the equipment.
177. The placement of process equipment and pipeline fittings in production buildings and on open areas shall ensure the safety of maintenance and operation, the possibility of carrying out repair work and of taking prompt measures to prevent emergency situations or to localise accidents.
178. The placement of process equipment and pipelines in premises and on outdoor installations, and of pipelines on trestles, shall be carried out taking into account the possibility of visual monitoring of their condition and of performing maintenance, repair and replacement work.
179. The process equipment of explosion and fire hazardous production facilities shall not be placed: above or below auxiliary premises; under the trestles of process pipelines carrying hazardous substances, except where special safety measures are taken that preclude hazardous substances from reaching equipment installed beneath them; above the areas of open pump and compressor units, except where hermetic pumps are used or where special safety measures are taken that preclude explosion and fire hazardous substances from reaching equipment installed beneath them. The special safety measures shall be justified by the results of a hazard analysis of the processes and by a quantitative analysis of the risk of accidents at the hazardous production facility in accordance with Appendix No. 1 to these Rules.
180. Equipment withdrawn from an operating process system shall be dismantled if it is located in the same premises as process units of explosion hazard category I and (or) II; in all other cases it shall be isolated from the operating process systems.
181. During the operation of process equipment and pipelines at hazardous production facilities of chemical, petrochemical and oil-and-gas refining production in which corrosion-active substances are handled, methods for their protection shall be provided, taking into account the rate of corrosion wear of the structural materials used.
182. Process equipment and pipelines in contact with corrosion-active substances shall be manufactured from corrosion-resistant metallic structural materials. In justified cases, corrosion-resistant non-metallic coatings (fluoroplastic, polyethylene) may be used to protect the equipment and pipelines. At installations with process units of explosion hazard category III, equipment and pipelines made of corrosion-resistant non-metallic materials, including composite materials (glass, porcelain, fluoroplastic, polyethylene), may be used, subject to appropriate justification confirmed by the results of research and to the development of safety measures.
183. The procedure for monitoring the degree of corrosion wear of equipment and pipelines using non-destructive methods, and the methods, frequency and locations for taking control measurements, shall be determined in the operational documentation taking into account the specific operating conditions (for new production facilities, on the basis of the results of special research) and shall comply with the requirements of TR CU 012/2011.
184. When selecting pumps (pump units) and compressors (compressor units) for hazardous production facilities of chemical, petrochemical and oil-and-gas refining production, the technical requirements for the safety of equipment for operation in explosive atmospheres and of the Rules shall be taken into account. Pumps and compressors used for transferring combustible and compressed gases, liquefied flammable gases, flammable liquids and combustible liquids are selected, in terms of reliability and design features, taking into account the physico-chemical properties of the products transferred and the regulated parameters of the process. In this case, the number of pumps and compressors is determined on the basis of ensuring the continuity of the process; in justified cases (confirmed by a reliability calculation), their redundancy is provided for.
185. The sequence of actuation of the interlock systems of pumps and compressors is determined by the actuation programme (algorithm) of the automatic emergency protection system (PAZ) of the process installation.
186. Shut-off fittings installed on the discharge and suction pipelines of a pump or compressor shall be located as close as possible to it and be situated in an area convenient for maintenance. A check valve is provided on the discharge pipeline if there is no other device preventing the reverse movement of the substances transported.
187. Pumps and compressors of the process units of explosion and fire hazardous production facilities whose stoppage, in the event of a voltage drop or a short-term power failure, may lead to deviations of the process parameters to critical values and to the development of accidents, shall be selected taking into account the possibility of their automatic restart and shall be equipped with motor self-start systems. The response time of the self-start system shall be less than the time for the process parameters to exceed the maximum permissible values.
188. Compressor units and pump units of explosion and fire hazardous production facilities shall undergo testing and acceptance in accordance with the requirements of Technical Regulation TR CU 012/2011 and the manufacturer's technical documentation.
189. The operation of compressor units and pump units shall not be permitted in the absence or faulty condition of the automation, monitoring and interlock systems specified in the manufacturer's technical documentation and provided for by the design of the installation in accordance with the requirements of TR CU 012/2011 and these Rules.
190. For discharging flammable liquids and combustible liquids, seal-less centrifugal pumps with a double mechanical seal shall be used, and in justified cases, pumps with a single mechanical seal with an additional sealing element. For liquefied hydrocarbon gases, hermetic (seal-less) centrifugal pumps or centrifugal pumps with a double mechanical seal of the tandem type shall be used. As the barrier liquid, non-combustible liquids and (or) liquids neutral to the pumped medium shall be used. Where justified in the design documentation (documentation for technical re-equipment), piston, plunger, diaphragm, screw and gear pumps may be used for discharging flammable liquids and combustible liquids at low volumetric delivery rates, including in metering systems. When selecting pumps, the requirements of TR CU 012/2011 and these Rules, as well as the requirements of the manufacturer's technical documents, shall be taken into account. Technical decisions on the selection of the type and kind of pumping equipment are taken by the design organisation when developing the design documentation (documentation for technical re-equipment) of the hazardous production facility, taking into account the physico-chemical properties of the flammable liquids and combustible liquids handled in the process and in the process flow scheme.
191. Centrifugal pumps with a double mechanical seal shall be equipped with systems for monitoring and signalling leakage of the sealing liquid. In the event of leakage of the sealing liquid, the sequence of operations for stopping the pumps and switching to the standby, and the need for interlocks forming part of the PAZ system, are determined by the project developer.
192. At installations with process units of explosion hazard category I and II, centrifugal compressors and pumps with mechanical seals shall be equipped with systems for monitoring the condition of the bearings by temperature, with an alarm that is actuated on reaching the limit values, and with interlocks forming part of the PAZ system, which shall be actuated when these values are exceeded. The sequence of operations for stopping the compressors and pumps and switching to the standby is determined by the project developer. The design of the compressors and pumps shall provide for the installation of bearing temperature monitoring sensors. Periodic or continuous instrument monitoring of the vibration level shall be established.
193. The manufacture, installation and operation of pipelines and fittings for combustible and explosive products shall be carried out taking into account the physico-chemical properties and process parameters of the media transported, as well as the technical requirements for the safety of equipment for operation in explosive atmospheres and these Rules.
194. In explosion and fire hazardous process systems, the use of metal hoses and flexible hoses (rubber, plastic) as stationary pipelines for transporting liquefied flammable gases, substances in a vapour-gas state, flammable liquids and combustible liquids shall not be permitted, with the exception of the piping of furnace burners. For performing auxiliary operations (purging of pipeline sections and pumps, removal of blow-off gases and vapours, freeing of pipelines from residues of liquefied flammable gases, flammable liquids and combustible liquids), specially designated equipment and stationary lines (headers) shall be used, on which branches (nozzles) with shut-off fittings and a blind flange are provided and, where necessary, a check valve is installed. Removable pipeline sections are used to connect the equipment and process pipelines to the stationary lines. The use of pipes made of composite materials as stationary pipelines is established in the initial data and is justified in the design documentation (documentation for technical re-equipment), taking into account the physico-chemical properties of the medium transferred and the regulated operating parameters of the pipeline. For carrying out draining and loading operations into railway tank cars and other non-stationary equipment, flexible hoses or metal hoses shall be used which have documents confirming their conformity with the mandatory requirements established in accordance with the legislation of the Russian Federation on technical regulation. The selection of hoses or metal hoses is carried out taking into account the properties of the product transported and the parameters of the process; the service life of metal hoses and hoses is established by the manufacturer and shall not be subject to extension.
195. In explosion and fire hazardous process systems in which, upon deviations from the regulated parameters, a detonation explosion in the pipelines is possible, measures shall be taken to prevent detonation phenomena and to prevent the transmission of the explosion to the apparatus connected by these pipelines.
196. The routing of pipelines shall ensure the shortest length of the lines and shall exclude sagging and the formation of stagnant zones.
197. When routing pipelines through the building structures of buildings and other obstacles, measures are taken to exclude the possibility of transmitting additional loads to the pipes. The transit routing of process pipelines carrying hazardous substances under buildings and structures shall not be permitted. When routing process pipelines through the bunds of tanks, the tightness of their passage shall be ensured.
198. Pipelines shall not have flanged or other detachable connections. Flanged connections may be used only at the points where fittings are installed or where pipelines are connected to apparatus, and on those sections where, under the process conditions, periodic disassembly is required for cleaning and repairing the pipelines.
199. Flanged connections are placed in locations that are open and accessible for visual observation, maintenance, disassembly, repair and installation. The placement of flanged connections of pipelines carrying fire and explosion hazardous, toxic and caustic substances above places intended for the passage of persons and above work areas shall not be permitted. The material of the flanges and the design of the seal are applied in accordance with the regulatory technical documents establishing requirements for process pipelines, taking into account the operating conditions. For process pipelines carrying explosive products at facilities that include process units of explosion hazard category I, the use of flanged connections with a smooth sealing surface shall not be permitted, except in cases where spiral-wound gaskets are used.
200. The design of the seal, the material of the gaskets and the installation of the flanged connections shall ensure the required degree of tightness of the detachable connection throughout the inter-repair operating period of the process system.
201. At the points where pipelines carrying combustible products are connected to a header, fittings are provided for their periodic shut-off. When pipelines of process units of explosion hazard category I are connected to a header, in justified cases, duplicating shut-off devices are provided to increase reliability.
202. On inter-unit pipelines carrying combustible and explosive media, remotely controlled shut-off fittings intended for the emergency shut-off of each individual process unit shall be installed. The fittings shall be installed in locations convenient for maintenance and repair, and for visual monitoring of their condition. On the pipelines of process units having QB <= 10, manually operated fittings may be installed. The location of the fittings shall ensure the minimum time for bringing them into action.
203. In process systems with units of any explosion hazard category, steel fittings shall be used that are resistant to the corrosive action of the working medium under operating conditions and that meet the requirements of TR CU 012/2011 and these Rules. Where justified in the design documentation (documentation for technical re-equipment), in process units having QB <= 10, fittings made of cast iron and non-metallic structural materials (plastics, glass) may be used, subject to appropriate justification (based on the results of special research) and to the development of additional safety measures under operating conditions. The safety measures are developed taking into account an analysis of operational failures to prevent the possibility of an accident occurring.
204. On pipelines for transporting explosion and fire hazardous products, fittings are installed in accordance with the design documentation. The tightness class of the closure element is determined in the design documentation (documentation for technical re-equipment) on the basis of the physico-chemical properties of the products transferred and the regulated parameters of the process.
205. On the pipelines of process units of explosion hazard category I with a medium pressure P > 2.5 MPa and a temperature equal to the boiling point of the medium at the regulated pressure, weld-end fittings shall be used to increase the reliability and tightness of the connections.
206. In process systems, to prevent accidents and to prevent their development, emergency-prevention devices shall be used: shut-off and shut-off-and-control fittings, valves, cut-off and other shut-off devices, safety devices against overpressure, means for the suppression and localisation of flame, and automatic explosion suppression systems.
207. The selection of the methods and means of the protection system, the development of the sequence of actuation of the protection elements, and the localisation and prevention of the development of accidents shall be determined in the design documentation (documentation for technical re-equipment) on the basis of the results of a hazard analysis of the process and an assessment of the explosion risk, based on an analysis of the schemes (scenarios) of the possible development of these accidents, taking into account the explosion hazard category of the process units included in the facility, and shall be reflected in the process regulations for the production of products. When designing software-controlled equipment, the risks associated with errors in the software shall be taken into account.
208. In process units of all explosion hazard categories and in all systems for regulating the ratio of combustible media to oxidisers, shut-off-and-control fittings meeting the requirements for speed of response and reliability shall be used as cut-off devices for emergency shut-off.
209. Technical devices (including shut-off fittings, valves and cut-off devices) intended for the emergency shut-off of a unit shall meet the requirements for the safety of equipment for operation in explosive atmospheres and shall ensure the protection of process systems in emergency modes with a specified speed of response: the speed of response of the shut-off devices installed on the pipelines of the heat transfer medium used for evaporating the combustible liquid is established in the design documentation (documentation for technical re-equipment); the pressure sources of installations with process units of explosion hazard category I and II shall be shut off simultaneously with the actuation of the cut-off fittings on the discharge lines, the speed of response of which is determined in the design documentation (documentation for technical re-equipment).
210. Technical devices (including fittings and valves) intended for supplying inhibiting and inert substances to process apparatus shall meet the requirements of TR CU 012/2011 and shall ensure, in emergency modes, the specified parameters for capacity and speed of response: in systems for supplying inert gas to process units of all explosion hazard categories, they shall ensure volumetric rates of inert gas input that exclude the formation of explosive mixtures in all possible cases of deviation of the process from the regulated values; in systems for introducing inhibiting substances into process units of all explosion hazard categories, they shall ensure the necessary volumetric rates of inhibitor supply to suppress uncontrolled exothermic reactions; on the lines for the organised discharge of combustible vapour-gas and liquid media from process units of all explosion hazard categories, they shall exclude the possibility of releasing these media into the atmosphere.
211. Upon actuation of the protective means installed on the equipment, the possibility of injury to the operating personnel and of the release of explosive products into the working zone and the environment shall be prevented.
212. The fittings, safety devices and flame-localisation means used for the explosion protection of process systems shall be manufactured in accordance with the requirements of TR CU 012/2011 and the requirements established in the manufacturer's technical documentation. At hazardous production facilities, technical devices are used which have documents confirming their conformity with the mandatory requirements established in accordance with the legislation of the Russian Federation on technical regulation.
213. When selecting, calculating and operating the means of protecting apparatus and lines against overpressure, the technical requirements for the safety of equipment for operation in explosive atmospheres and the technical requirements established by the regulatory documents containing requirements for the selection, calculation and operation of the means of protecting apparatus and lines against overpressure shall be taken into account. When installing safety devices on process apparatus (pipelines) with explosion and fire hazardous products, measures and means (including automatic process control) shall be provided to ensure the minimum frequency of their actuation.
214. Means of protection against flame propagation (flame arresters, flame cut-offs, liquid seals) shall be installed on the breathing and relief lines of apparatus and tanks containing flammable liquids and combustible liquids, and on pipelines carrying flammable liquids and combustible liquids in which flame propagation is possible, including those operating intermittently or with an unfilled pipeline cross-section, and on pipelines from equipment with a red-hot catalyst, flame combustion and other ignition sources. Means of protection against flame propagation are not installed provided that inert gases are supplied to these lines in quantities that exclude the formation of explosive mixtures in them. The procedure for supplying inert gases is established in the process regulations for the production of products. The design of the flame arresters and liquid safety seals shall ensure reliable flame localisation, taking into account the operating conditions.
215. For flame arresters and liquid safety seals, measures are provided to ensure the reliability of their operation under operating conditions, including where crystallisation, polymerisation and freezing of substances in the seal are possible. For flame arresters installed on the breathing lines of tanks containing flammable liquids and combustible liquids, where dust deposition is possible owing to its ingress from atmospheric air, measures are provided for monitoring the condition of the flame arresters (including monitoring their throughput capacity) and for preventing the risk of emergency situations arising.
216. In tanks containing flammable liquids that operate under pressure, when a vacuum arises in them, to dissipate it and to exclude the formation of an explosive atmosphere in them, the supply of a gas that is inert with respect to the medium in the tank shall be provided. For tanks containing flammable liquids that operate without pressure, measures shall be provided to prevent the formation of explosive mixtures in them or to exclude ignition sources.
217. The operation of explosion and fire hazardous process installations with faulty or disconnected emergency-prevention devices and systems for supplying inert and inhibiting substances shall not be permitted. The condition of the emergency protection means and of the systems for supplying inert and inhibiting substances shall be monitored periodically. The frequency and methods of monitoring are determined in the design documentation (documentation for technical re-equipment) and are established in the process regulations for the production of products.
218. Systems for the monitoring, automatic and remote control and regulation of processes (hereinafter - control systems), signalling systems and PAZ systems, as well as systems for communication and warning of emergency situations (hereinafter - CiO systems), including those supplied complete with the equipment, shall meet the requirements of these Rules, the design documentation (documentation for technical re-equipment) and the process regulations for the production of products, and shall ensure the specified accuracy of maintaining the process parameters and the reliability and safety of carrying out the processes.
219. The selection of the monitoring, control and PAZ systems, and also of the CiO systems, according to their indicators of safety, reliability, speed of response, permissible error of the measuring systems and other technical characteristics, is carried out taking into account the features of the process, depending on the explosion hazard category of the process units included in the facility.
220. The monitoring, control and PAZ systems shall undergo integrated testing according to special programmes.
221. The placement of the electrical means and elements of the monitoring, control and PAZ systems, and also of the communication and warning systems, in the explosion-hazardous zones of production premises and outdoor installations, and their degree of explosion protection, shall comply with the requirements of the regulatory and technical documents on the arrangement of electrical installations.
222. In explosion-hazardous premises and outside them, in front of the entrance doors, light and sound signalling of gas contamination of the air is provided.
223. The automation means used under the action plan for the localisation and elimination of the consequences of accidents (PMLA) shall be marked at their installation location and are indicated in the process regulations for the production of products and in the instructions.
224. The systems for monitoring, control and PAZ of processes, and also the CiO systems, shall be marked with the application of appropriate inscriptions clearly reflecting their functional purpose, the values of the protection set points and the regulated values of the monitored parameters.
225. The placement of the monitoring, control and PAZ systems, and also of the CiO systems, is carried out in locations that are convenient and safe for maintenance and that exclude vibration whose quantitative characteristics exceed the permissible values of the vibration indicators for the technical means used, contamination by substances handled in the process, and mechanical and other harmful effects affecting the accuracy, reliability and speed of response of the systems. At the same time, measures and means for dismantling the systems and their elements without depressurising the equipment and pipelines shall be provided.
226. Hazardous production facilities that include objects with process units of explosion hazard category I and II shall be equipped with automatic and (or) automated control systems built on the basis of electronic monitoring and automation means, including computer technology.
227. Automated process control systems (hereinafter - APCS) based on computer technology shall meet the requirements of the technical assignment and shall ensure: continuous monitoring of the process parameters and control of the operating modes to maintain their regulated values; registration of actuation and monitoring of the operable condition of the PAZ means; continuous monitoring of the condition of the air within the facility; continuous analysis of changes in the parameters towards critical values and forecasting of a possible accident; actuation of the control and PAZ means that halt the development of a hazardous situation; actuation of the means for localising and liquidating accidents, and selection and implementation of optimal control actions; carrying out operations for accident-free start-up and shutdown and all the switchings necessary for this; issuing information on the state of safety at the facility to the higher-level control system and to the industrial safety remote monitoring system. Information on events associated with deviations from the parameters determining the explosion hazard of the process in accordance with the requirements of paragraph 218 of these Rules shall be archived (with an entry in the event log) in the APCS of the operating organisation. Entries in the event logs shall be kept for three months.
228. In control rooms, light and sound signalling shall be provided that is actuated on reaching the warning values of the process parameters determining its explosion hazard.
229. PAZ systems shall ensure the protection of personnel, process equipment and the environment in the event of an abnormal situation arising at the controlled object, the development of which may lead to an accident.
230. PAZ systems function independently of the process control system. A malfunction of the control system shall not affect the operation of the PAZ system. The information exchange networks between the elements of the PAZ system shall be separate from the information exchange networks between the elements of other APCS systems.
231. The PAZ system performs the following functions: automatic detection of potentially hazardous changes in the state of the process object or of its automation system; automatic measurement of the process variables important for the safe conduct of the process (for example, the measurement of variables whose values characterise the proximity of the object to the boundaries of the safe process operating mode); automatic (on-line) diagnostics of failures occurring in the PAZ system and (or) in the hardware and software means it uses; automatic pre-accident signalling informing the process operator of potentially hazardous changes that have occurred in the object or in the PAZ system; ensuring the safe shutdown or transfer of the explosion-hazardous process to a safe state according to a set programme when the maximum permissible values of the process parameters are exceeded; automatic protection against unauthorised access to the settings parameters and (or) the selection of the operating mode of the PAZ system; automatic monitoring of the operator's control actions, the issuing of warning messages about incorrect actions and their registration when performing start-up, operational and shutdown operations; automatic determination of the root cause and sequence of actuation of the PAZ system.
232. In addition to the logic controller, manual means of initiating the emergency protection system (individual emergency protection loops) may be provided, for example emergency shutdown buttons connected directly to the emergency protection controller. The choice of the connection option for the emergency shutdown buttons is made by the design organisation, taking into account the complexity of the process facility, the need to carry out the equipment emergency shutdown sequence, and the risk of failure of the emergency protection controller.
233. The methods for creating emergency protection systems shall be determined in accordance with the required safety integrity level (SIL), determined at the requirements-formation stage during the design of the automated process control system on the basis of a hazard and operability analysis of the safety loops, taking into account the risk arising on failure of a safety loop. A rational choice of the means for emergency protection systems is made taking into account their reliability and response speed in accordance with their technical characteristics.
234. For facilities that include process units of categories I and II, the emergency protection control systems shall use their own sensors. To ensure the required safety integrity level, sensors of other subsystems of the automated process control system may be used as additional sources of information. In this case, compliance with the requirements of paragraphs 230 and 231 of these Rules shall be ensured, and the additional elements of the emergency protection system shall ensure the required safety integrity level. Failure of the sensors of other automated process control systems used as additional sources of information for emergency protection systems shall not lead to an increase in demands on the emergency protection system to perform its functions.
235. For facilities that include process units of categories I and II, the emergency protection systems shall use their own actuating devices. Where additionally justified in the design documentation (documentation for technical re-equipment), actuating devices provided as part of other subsystems of the automated process control system may be used as actuating devices of the emergency protection system, provided that the following requirements are complied with: the actuating device shall be equipped with two additional units acting on the actuating mechanism, one of which is connected to the emergency protection system and the second to the automated process control subsystem; signals coming from the additional unit of the actuating mechanism connected to the emergency protection system shall have priority over signals coming from the additional unit of the actuating mechanism connected to another automated process control subsystem. In this case, compliance with the requirements of paragraphs 230 and 231 of these Rules shall be ensured; signals coming from the additional unit of the actuating mechanism connected to the emergency protection system shall move the shut-off (shut-off and control) element of the actuating device to a safe position and make it impossible to control the actuating mechanism by signals coming from the additional unit of the actuating mechanism connected to another automated process control subsystem; failure of another automated process control subsystem shall not affect the performance of the safety function of the corresponding emergency protection loop.
236. Monitoring of the current values of the parameters that determine the explosion hazard of process operations involving units of explosion hazard category I is carried out using no fewer than two independent sensors with separate sampling points, interacting logically to trigger the emergency protection system.
237. The design of the emergency protection system and the selection of its elements are carried out on the basis of conditions that ensure the operation of the system during operation, maintenance and repair throughout the entire life cycle of the protected facility.
238. The reliability, safety and response-speed indicators of emergency protection systems are determined by the system developers, taking into account the requirements of the process part of the project. In this case, the explosion hazard category of the process units included in the facility and the development time of a possible accident are taken into account.
239. The response time of the protection system shall be such that the dangerous development of a possible accident is prevented.
240. The following requirements apply to the performance of the control functions of emergency protection systems: control commands formed by the protection (interlock) algorithms shall have priority over any other commands for controlling process equipment, including commands formed by the operating personnel of the automated process control system (unless otherwise stipulated in the technical specification (hereinafter - the TS) for its creation); the activation of one emergency protection system shall not lead to the creation at the facility of a situation requiring the activation of another such system; the protection activation algorithms shall provide for the possibility of enabling the blocking of control commands for equipment technologically connected with the apparatus, unit or other equipment that caused such activation.
241. In emergency protection and process control systems of any explosion hazard category, their activation by short-term signals indicating a disturbance of the normal course of the process, including in the event of switching to a standby or emergency power supply source, shall be prevented.
242. In the design documentation (documentation for technical re-equipment), the process regulations for product manufacture and the lists of emergency protection systems of explosion-hazardous facilities, in addition to the protection setpoints for hazardous parameters, the limits of the regulated parameter values and the limits of the critical parameter values shall be indicated.
243. The setpoint values of the protection systems are determined taking into account the actuation errors of the signalling devices of the measuring instruments, the response speed of the system, the possible rate of change of the parameters and the explosion hazard category of the process unit. In this case, the response time of the protection systems shall be less than the time required for a parameter to move from the warning value to the maximum permissible value. The specific setpoint values are given in the design documentation (documentation for technical re-equipment) and the process regulation for product manufacture.
244. For hazardous production facilities of chemical, petrochemical and oil and gas refining production, a pre-emergency alarm based on the warning values of the parameters determining the explosion hazard of the facilities is provided.
245. In the event of a power outage or a cessation of the supply of compressed air to power the monitoring and control systems, the emergency protection systems shall ensure the transfer of the process facility to a safe state. The possibility of accidental (unprogrammed) switching in these systems when power is restored shall be excluded. The return of the process facility to the operating state after the activation of the emergency protection system is performed by the operating personnel in accordance with the instructions.
246. The actuating mechanisms of emergency protection systems shall have end-position indicators directly on these mechanisms. The signals indicating the end positions of the actuating mechanisms of the emergency protection system shall be supplied to the controller of the emergency protection system.
247. The reliability of emergency protection systems is ensured by hardware redundancy of various types (duplication, triplication), temporal and functional redundancy, and the presence of diagnostic systems with indication of the operating state and self-diagnostics with comparison of the values of technologically related parameters. The sufficiency of the redundancy and its type are justified by the project developer.
248. The reliability indicators of emergency protection systems are established and verified for no fewer than two types of failure of these systems: "failure to operate" type failures and "false operation" type failures.
249. The technical solutions for ensuring the reliability of monitoring parameters that have critical values at facilities with process units of explosion hazard category III are justified by the developer of the design documentation (documentation for technical re-equipment).
250. All computer software intended for use as part of any emergency protection system shall be subject to mandatory verification of compliance with the requirements specified in the TS, which is carried out by its manufacturer or supplier in accordance with a programme agreed with the customer of the emergency protection system.
251. The list of monitored parameters that determine the explosion hazard of the process in each specific case is compiled by the process developer and indicated in the initial design data.
252. For the periods of start-up, shutdown and switching of the process modes of installations, where appropriately justified in the design documentation (documentation for technical re-equipment) and the process regulations for product manufacture, special algorithms (scenarios) for the operation of the emergency protection system shall be provided, under which the manual or automatic disabling of individual interlocks is permitted. The monitoring, indication and recording of parameters shall not be subject to disabling.
253. For monitoring gas contamination against the maximum permissible concentration and the lower concentration limit of flame propagation in production premises and in the working area of open outdoor installations, automatic gas monitoring and analysis means with an alarm that operates on reaching the maximum permissible values and with the issuing of signals to the emergency protection system shall be provided. The locations and type of the automatic continuous gas monitoring and analysis means with an alarm for monitoring gas contamination in the working area of production premises and open outdoor installations are established and justified in the design documentation (documentation for technical re-equipment) in accordance with the technical characteristics of the means (instruments) specified in the manufacturer's data sheets. In this case, all instances of gas contamination shall be recorded by instruments with automatic recording and documented.
254. The monitoring, control and emergency protection systems of facilities with process units of explosion hazard category I are, with respect to ensuring the reliability of the power supply, classified as a special group of category I electrical loads in accordance with the requirements of the regulatory and technical documents on the arrangement of electrical installations. The classification of the monitoring, control and emergency protection systems of facilities with process units of explosion hazard categories II and III as a special group of category I electrical loads shall be determined in the design documentation (documentation for technical re-equipment).
255. The power of the third independent power supply source intended to power the monitoring, control and emergency protection systems of facilities with process units of explosion hazard category I shall ensure the operation of all elements of the system involved in the accident-free shutdown of the process facility.
266. For pneumatic control and emergency protection systems, compressed air networks separate from the process air networks shall be provided.
267. The air for air compressors and instrumentation and automation systems shall be cleaned of dust, oil and moisture. The quality of the compressed air shall comply with the requirements established by the manufacturer in the technical documentation (data sheets) for the systems and the control and measuring instruments.
268. The compressed air supply systems for control and emergency protection means shall have buffer tanks (receivers) that supply air to the monitoring, control and emergency protection systems when the compressors stop for a time sufficient for the accident-free shutdown of the facility, which shall be confirmed by calculation. The use of compressed air for control and emergency protection means for purposes other than intended shall not be permitted.
269. On the compressed air inlet lines to the workshop (process installation), instruments or sampling devices for analysing the contamination of the compressed air shall be provided. The frequency of the analyses shall be specified in the instructions.
270. The control rooms of process facilities and the air compression installations shall be equipped with light and sound alarms that operate when the pressure of the compressed air in the network upstream of the buffer tanks (receivers) drops.
271. The use of inert gas to power instrumentation and automation systems shall not be permitted.
272. The metrological assurance and functioning of the instruments and monitoring, control and emergency protection systems in the organisation operating the hazardous production facility shall comply with the requirements of Federal Law No. 102-FZ of 26 June 2008 "On Ensuring the Uniformity of Measurements" (Collected Legislation of the Russian Federation, 2008, No. 26, Art. 3021; the official internet portal of legal information http://pravo.gov.ru, 2020).
273. The measuring instruments included in the monitoring, control and emergency protection system, and the information and measurement systems (hereinafter - IMS), shall have documents confirming the type approval of the measuring instruments and the completion of verification and/or calibration.
274. The space-planning solutions, the design of buildings, premises and auxiliary structures for the monitoring, control, emergency protection and gas analysis systems, and their placement on the territory of hazardous production facilities of chemical, petrochemical and oil and gas refining production shall comply with the design documentation, the requirements of the technical regulations, the requirements of the legislation on urban development activities and these Rules.
275. The control rooms shall be free-standing. In individual cases, where appropriately justified in the project, they may be built onto buildings. In this case, the following shall not be permitted: placement above (below) premises that are explosion- and fire-hazardous, premises with a chemically active and harmful environment, supply and exhaust ventilation chambers, or premises with wet processes; the placement in them of equipment and other devices not connected with the process control system; the transit routing of pipelines, air ducts and cables through the control rooms; the provision of steam or water heating; the introduction of impulse lines and other pipelines carrying combustible, explosive and harmful products.
276. In the control rooms, the following shall be provided: air heating and air-conditioning installations (the provision of water heating in control rooms that do not contain electronic instruments is justified in the project). The air supplied to the control rooms shall be cleaned of gases, vapours and dust and shall comply with the requirements for the operation of the installed equipment and with the sanitary standards; warm and non-electrically-conductive floors, cable channels and double floors that comply with the requirements of the legislation on urban development activities; light and sound alarms for gas contamination of the production premises and the territory of the controlled facility.
277. For emergency protection systems, in justified cases, boards (or panels) with mnemonic diagrams of the interlock structure shall be provided, which shall be equipped with light devices signalling the state of the interlocks, the power supply sources and the actuating elements.
278. The placement of analyser rooms (buildings) on the site of a process installation (workshop) is justified in the design documentation in accordance with the requirements of the legislation on urban development activities and these Rules. The volume of the analyser room and the technical characteristics of the ventilation systems shall be determined on the basis of conditions under which, within one hour, the possibility of the formation in the room of an explosive concentration of the products being analysed in the event of a complete rupture of the gas supply tube of one analyser, regardless of their number in the room, is excluded, given the presence of flow and pressure limiters for these products. In addition to the general-exchange ventilation, emergency ventilation shall be provided in the room, which is automatically switched on if the concentration of the substances in circulation in the air of the room reaches 20 per cent of the lower concentration limit of flame propagation.
279. Sampling tubes with a pressure higher than that required for the operation of the analyser shall not be introduced into the analyser room. The flow and pressure limiters on the sampling devices shall be located in a safe place outside the analyser room. The excess of the substance being analysed, after the completion of the analysis, shall be returned to the process system or disposed of.
280. Cylinders with verification gases and mixtures, carrier gases and reference standards shall meet the requirements of the federal norms and rules of industrial safety that establish requirements for equipment operating under excess pressure. The locations and procedure for the placement, storage and use of the cylinders are determined by the project.
281. In analyser rooms, the permanent presence of people shall not be permitted.
282. Analysers shall have protection against the propagation of flame along the gas (gas supply) lines.
283. Production facilities that include process units of any explosion hazard category shall be equipped with systems of two-way loudspeaker and telephone communication between technologically connected production areas, and shall also be equipped with telephone communication with the personnel of the dispatch points. Facilities that include process units of explosion hazard category I shall be equipped with systems of two-way loudspeaker communication with the personnel of the dispatch points, the civil defence headquarters (hereinafter - CD) of the industrial facility, the gas rescue service (hereinafter - GRS), the fire station (hereinafter - FS), the loading and unloading points, and the warehouses and pumping stations for combustible, liquefied and harmful products. The list of production subdivisions with which communication is established, and the type of communication, are determined by the project developer depending on the features of the process, the production conditions, taking into account the explosion hazard category of the process units included in them, and other factors.
284. In process units of all explosion hazard categories, technical means shall be provided that ensure, in automatic mode, the notification of the detection, containment and elimination of releases of hazardous substances. The information, including forecasting data on the paths of possible spread of an explosive (or harmful chemical) cloud, shall be transmitted to the GRS of the industrial facility and to the dispatcher of the industrial facility (organisation), and also to the unified duty-dispatch service of the municipal formation at the location of the hazardous production facility.
285. In the control rooms of production facilities that include units of explosion hazard category I, at outdoor installations, in the room of the dispatcher of the enterprise, of the structural subdivision of the enterprise specially authorised to address tasks in the field of civil defence and the protection of the population and territories from emergency situations, and at the unified duty-dispatch service of the municipal formation, the installation of control posts and technical means of communication and notification for warning of hazardous releases of chemically hazardous substances is provided. The means of communication and notification shall, in their external appearance, differ from similar means for industrial use; their placement and arrangement shall prevent access by unauthorised persons and the possibility of accidental use. The signalling devices of the notification systems are sealed.
286. The organisation and procedure for notifying production personnel and the civilian population of an accident, the appointment of a person responsible for switching on (starting) the notification system, and the procedure for creating and maintaining in a state of readiness the technical means of communication and notification and the corresponding emergency rescue services for eliminating the threat of chemical injury are carried out in accordance with the legislation of the Russian Federation in the field of civil defence and the protection of the population and territories from emergency situations, taking into account the Regulation on Population Notification Systems, approved by Order No. 578/365 of the Ministry of the Russian Federation for Civil Defence, Emergencies and Elimination of Consequences of Natural Disasters (EMERCOM of Russia) and the Ministry of Digital Development, Communications and Mass Media of the Russian Federation (Minkomsvyaz of Russia) of 31 July 2020, registered by the Ministry of Justice of the Russian Federation on 26 October 2020, reg. No. 60567.
287. Monitoring shall be established over the correct operation of the monitoring, control and emergency protection, communication and notification systems. The scope of the monitoring shall ensure the stable and accurate operation of the monitoring, control and emergency protection systems.
288. Process operations and the operation of equipment shall not be carried out with faulty or disabled monitoring, control and emergency protection, communication and notification systems.
289. For continuous processes, with the written permission of an official of the organisation, the disabling of the protections (no more than one parameter at a time) is permitted only during the day shift, or, when work is carried out in other shifts, the presence and supervision of the relevant services shall be ensured. In this case, organisational and technical activities and a work organisation plan that ensure the safety of conducting the process and carrying out the work are developed. The duration of the disabling shall be determined by the work organisation plan. The disabling of the pre-emergency alarm in this case shall not be permitted. Manual deblocking in automatic process control systems shall not be permitted. In this case, devices that record all instances of disabling of the protection parameters and their duration are provided.
290. For the period of replacement of elements of the monitoring or control system, measures and means shall be provided that ensure the safe conduct of the process in manual mode. In the design documentation of the hazardous production facility (documentation for the technical re-equipment of the hazardous production facility), in the process regulation for product manufacture and in the process instructions, the stages of the process or individual parameters the control of which in manual mode shall not be permitted shall be defined.
291. For facilities with process units of any explosion hazard category, instruments, devices and other elements that have exceeded their assigned service life shall not be used in the monitoring, control and emergency protection, and communication and notification systems.
292. The shift process personnel, upon detection of a malfunction of an instrument or automation means, shall carry out the emergency shutdown of the failed instruments and automation means in accordance with the requirements of the operating instructions for the automation means. The organisation of the repair of the disconnected instruments, and the commissioning and repair of the monitoring, control and emergency protection systems, shall be carried out by the workers of the instrumentation and automation service or of a specialised organisation, provided that documents for carrying out the commissioning and repair of the monitoring, control and emergency protection, communication and notification systems at the hazardous production facility are available.
293. Shut-off and control valves and actuating mechanisms involved in the monitoring, control and emergency protection, and communication and notification schemes of the process operations, after repair and before installation in place, shall undergo periodic testing for response speed, strength and tightness of closure, with the drawing up of reports or with an entry in the data sheet or logbook. The frequency of the tests is established by the requirements in the manufacturer's technical documentation.
294. Work on the installation, commissioning, repair, adjustment and testing of the monitoring, control and emergency protection, and communication and notification systems shall exclude spark formation. For carrying out such work in explosion-hazardous zones, a permit to work is drawn up, and measures ensuring the safety of the organisation and conduct of the work are developed.
295. When removing monitoring, control and emergency protection, and communication and notification means for repair, commissioning or verification, immediate replacement of the removed means with means identical in all parameters shall be carried out.
296. The repair of technical devices, measuring and automation systems made in an explosion-proof design shall be carried out in accordance with the manufacturer's instructions.
297. The arrangement, installation, maintenance and repair of electrical installations shall comply with the requirements of TR CU 012/2011, the technical regulation of the Customs Union "On the Safety of Low-Voltage Equipment", approved by Decision No. 768 of the Customs Union Commission of 16 August 2011 (the official website of the Customs Union Commission http://www.tsouz.ru/, 2 September 2011), which is binding on the Russian Federation in accordance with the Treaty on the Eurasian Economic Union of 29 May 2014, ratified by Federal Law No. 279-FZ of 3 October 2014 "On the Ratification of the Treaty on the Eurasian Economic Union" (Collected Legislation of the Russian Federation, 2014, No. 40, Art. 5310), and with these Rules.
298. The power supply of facilities that include process units of explosion hazard category I shall be provided under reliability category I. In this case, the possibility of the accident-free transfer of the process to a safe state in all operating modes of the production, including in the event of the simultaneous cessation of the supply of power from two independent mutually redundant power supply sources, shall be ensured.
299. The electrical loads of process systems that include units of explosion hazard categories II and III shall, depending on the specific operating conditions and the features of the process, with respect to ensuring the reliability of the power supply, be classified as category I or II electrical loads.
300. Power supply lines from external sources, regardless of the voltage class, supplying consumers of the special group of power supply reliability category I, shall not be equipped with automatic frequency load-shedding devices (hereinafter - AFLS).
301. The laying of cables on the territory of enterprises and installations may be carried out openly: on overpasses, in galleries and on the cable structures of process overpasses. Cable structures on process overpasses shall be located taking into account the provision of the possibility of installing and dismantling pipelines in accordance with the requirements of the regulatory and technical documents on the arrangement of electrical installations. The laying of cables in channels filled with sand and in trenches is also permitted. Cables laid on the territory of process installations and production facilities shall have insulation and a sheath made of materials that do not propagate combustion.
302. The electric lighting of outdoor process installations shall have remote switching-on from the operator room and local switching by service zones.
303. When carrying out repair work in cramped conditions and possible gas contamination, including inside process apparatus, lighting shall be provided by means of portable explosion-protected battery-powered luminaires in a design corresponding to the environment, or portable electric luminaires in an explosion-proof design that meet the requirements of the technical regulations and other regulatory and technical documents on the arrangement of electrical installations.
304. The power supply of the emergency lighting of workplaces shall be provided under the special group of reliability category I.
305. On high-rise columns, apparatus and other process equipment, the obstruction lights shall be of an explosion-protected design.
306. Process installations and production facilities shall be equipped with a stationary network for connecting welding electrical equipment.
307. For connecting welding machines, switching boxes (cabinets) shall be used.
308. The network for connecting welding machines shall be de-energised before the start of work. The supply of voltage to this network and the connection of welding electrical equipment shall be carried out in accordance with the requirements of the technical regulations and other regulatory and technical documents on the safe operation of electrical installations.
309. Electric welding work shall be carried out in accordance with the instructions for carrying out hot work approved by the organisation operating the hazardous production facility.
310. Devices for connecting mobile and portable electrical equipment shall be located outside explosion-hazardous zones.
311. Heating and ventilation systems shall, in their purpose, arrangement, technical characteristics, design, maintenance and operating conditions, comply with the requirements of the technical regulations and these Rules.
312. The arrangement of ventilation systems, including emergency ventilation, and the air exchange rate shall be determined by the need to ensure reliable and effective air exchange. For premises with process units of any explosion hazard category, an assessment of the possibility of using all types of ventilation in the event of emergency, burst, maximum possible releases of combustible and toxic products from the process equipment into the premises shall be carried out during design and reflected in the operational documentation.
313. The procedure for the operation, maintenance, repair, commissioning and instrumental checking of the effectiveness of the operation of ventilation systems shall be defined by the operating instructions for industrial ventilation and shall comply with the requirements of Federal Law No. 384-FZ of 30 December 2009 "Technical Regulation on the Safety of Buildings and Structures" (Collected Legislation of the Russian Federation, 2010, No. 1, Art. 5; 2013, No. 27, Art. 3477).
314. The air intake for supply ventilation systems shall be provided from places that exclude the entry into the ventilation system of explosive and chemically hazardous vapours and gases under all operating modes of the production.
315. The arrangement of the releases from general-exchange and emergency exhaust ventilation systems shall ensure effective dispersion and exclude the possibility of an explosion in the release zone and the formation of explosive mixtures above the site of the hazardous production facility, including near stationary sources of ignition.
316. The local exhaust system removing explosion- and fire-hazardous dust and gases shall be equipped with interlocks that exclude the start-up and operation of the process equipment structurally connected with it when the exhaust is not operating.
317. Emergency ventilation systems shall be equipped with means for their automatic switching-on upon the operation of the pre-explosion concentration signalling devices installed in the premises, or of the gas analysers when the maximum permissible concentrations of harmful substances are exceeded.
318. In ventilation systems, measures and means shall be provided that exclude the entry of explosion- and fire-hazardous vapours and gases through the air ducts from one room to another.
319. The design of the ventilation equipment, air ducts and elements for exhaust ventilation systems (gates, dampers, valves) shall provide for the exclusion of a source of ignition of mechanical (impact, friction) or electrical (static electricity) origin. Fans shall comply with the technical requirements of TR CU 012/2011, the requirements of the regulatory technical documents and the manufacturer's documents.
320. The air ducts of supply ventilation systems, and the points where their sections are joined to each other and to the fans, shall be airtight and shall exclude the entry of air containing explosive vapours and gases into the supply ventilation system.
321. For exhaust ventilation systems on the internal surfaces of whose air ducts and equipment (fans) the formation (condensation, deposition) of liquid or solid explosion- and fire-hazardous products is possible, cleaning of the systems free of these products shall be provided for and carried out at intervals specified in the operating manual (instructions).
322. The electrical equipment of ventilation systems installed in production premises, outside the building and in the premises of the ventilation equipment (ventilation chambers) shall comply, in terms of levels and types of explosion protection, groups and temperature classes, with the requirements of TR TS 012/2011.
323. All metal air ducts and equipment of ventilation systems (supply and exhaust) shall be earthed in accordance with the requirements of the regulatory and technical documents on the installation of electrical installations.
324. In control rooms and production premises, signalling of the faulty operation of ventilation systems shall be provided for.
325. In premises that have explosion-hazardous zones, air heating combined with supply ventilation is provided. Water or steam heating of premises is used provided that the substances handled in the process do not form explosion-hazardous products with water, and this is confirmed by the adopted design engineering solutions. The maximum temperature of the heating surfaces of heating systems shall not exceed 80 per cent of the self-ignition temperature of the substance having the lowest self-ignition temperature among the substances handled in the process.
326. The arrangement of heating systems (water, steam), the elements and fittings used and their location when routed above electrical premises and instrumentation and control premises shall preclude the ingress of moisture into these premises under all modes of operation and maintenance of these systems.
327. The heat-carrier inlet unit is located in: the premises of supply ventilation systems (in the ventilation chamber); a separate room with a dedicated entrance from a stairwell or from non-explosion- and fire-hazardous production premises; production premises in which the use of water or steam heating is provided for.
328. The design, construction and operation of the water supply and sewerage systems of explosion- and fire-hazardous production facilities shall be carried out in accordance with the requirements of the technical regulations, the legislation on town-planning activities and these Rules. The composition of the effluents discharged from the plant-wide treatment facilities is established in the process regulations for the manufacture of products in accordance with the established requirements.
329. For each process facility, the possible compositions, temperature and quantity of the industrial effluents directed into the sewerage system shall be determined. The arrangement for draining effluents from the various facilities shall preclude the formation of sediments and the clogging of the sewerage system and, where mixing occurs, the possibility of the formation of explosion-hazardous products and solid particles.
330. Maintenance, repair and other work on water supply and sewerage systems classified as gas-hazardous shall be carried out in accordance with the instructions.
331. The sewerage systems of process facilities shall ensure the removal and treatment of chemically contaminated process, wash-off and other effluents generated both under the regulated operating modes of production and in cases of emergency releases. The discharge of these effluents into the main sewerage network without prior treatment, except in cases where the main network is intended for receiving such effluents, shall not be permitted.
332. Measures for the treatment of effluents and the removal of explosion- and fire-hazardous products shall preclude the possibility of the formation of an explosion-hazardous concentration of vapours and gases in the sewerage system.
333. Process facilities shall have local treatment facilities, the need for which is substantiated in the design.
334. Local treatment facilities shall be equipped, at the inlet and outlet of the discharge streams, with means for monitoring the content of explosion-hazardous products and for signalling the exceedance of the permissible values.
335. The treatment facilities of installations with process units of any explosion-hazard category, where surge discharges of explosion- and fire-hazardous products into the sewerage system are possible, shall be equipped with means for the automatic monitoring of and signalling of their content in the production effluents and of the presence of maximum permissible concentrations and of the lower concentration limit of flame propagation in the working zone of outdoor installations. The monitoring means are selected taking into account the specific conditions of the effluent treatment processes and their composition and are substantiated in the design documentation (the documentation for technical re-equipment).
336. It shall not be permitted to locate wells on sewerage networks beneath the racks of process pipelines or within the kerbs and bunds of the equipment of outdoor installations containing explosion-hazardous products.
337. The water supply of process facilities shall, in each specific case, be carried out taking into account the features of the process and the prevention of accidents and releases of explosion- and fire-hazardous products into the environment. For installations with process units of explosion-hazard category I, depending on the specific conditions of conducting the process, backup water supply sources with a system for their automatic activation are provided for.
338. The water supply of process systems shall be carried out using a closed water-circulation system. The power supply of the water-circulation system shall be provided at the same reliability category as that of the process facilities that consume the circulating water. For process facilities with units of any explosion-hazard category and process facilities with increased heat-removal requirements (apparatus with exothermic processes), the circulating water supply shall be carried out using water-treatment systems that preclude a reduction in the efficiency of heat exchange and the clogging of heat-exchange apparatus.
339. The circulating water supply systems of process facilities shall be equipped with means for the monitoring of and signalling of the presence of explosion- and fire-hazardous and toxic substances in the water-circulation system at the outlet from the process apparatus (at the manifold). At the same time, measures shall be taken to preclude the ingress of these substances into the water-circulation system. The quantity, type and installation locations of the monitoring systems are established in the design documentation (the documentation for technical re-equipment).
340. The direct connection of the sewerage system for chemically contaminated effluents to the domestic sewerage system without water seals shall not be permitted. Where explosion- and fire-hazardous and toxic substances may enter the effluents, means for the monitoring of and signalling of their content at the outlet from the installations (at the manifold) shall be provided for, as well as measures to preclude the ingress of these substances into the domestic sewerage system.
341. The siting of an enterprise that includes explosion-hazardous process facilities, the layout of its territory and the volumetric-planning solutions of the construction facilities shall be carried out in accordance with the requirements of the legislation on town-planning activities.
342. On the territory of an enterprise that includes explosion- and fire-hazardous production facilities, the presence of natural ravines, hollows and low-lying areas and the arrangement of open trenches, excavation pits and sumps in which explosion- and fire-hazardous vapours and gases may accumulate shall not be permitted. The trench and above-ground laying of pipeline routes carrying liquefied combustible gases, flammable liquids and combustible liquids in artificial or natural depressions shall not be permitted.
343. Process facilities, premises for production, administrative-economic and welfare purposes and places of the permanent or temporary presence of persons who, in the event of an accident, are within the hazardous zone shall be equipped with systems for notifying personnel of an accident at the process facility. The action plan for the localisation and elimination of the consequences of accidents shall provide for measures to move to a safe place persons not directly engaged in the work to eliminate the accident.
344. For newly designed explosion- and fire-hazardous and chemically hazardous production facilities, the following requirements shall be met: protection shall be ensured for personnel permanently present in the control room (operator rooms), administrative and other buildings in which the permanent presence of people is envisaged, against the effect of the blast wave (injury) in the event of possible emergency explosions at process facilities, taking into account the destruction zones, and also against thermal effect; the uninterrupted functioning shall be ensured of the automated systems for monitoring and control and of the automatic emergency protection (PAZ) for transferring the processes to a safe state and for the emergency shutdown of process facilities. The explosion resistance of the building structures of buildings is regulated by the requirements of the legislation on town-planning activities and by regulatory and technical documents.
345. Calculations of the mass of the substance participating in the explosion and of the radii of the destruction zones shall be carried out in accordance with Appendix No. 3 to these Rules. To substantiate other models, calculation methods and computer programs, including foreign ones, the following shall be indicated in the design documentation (the documentation for technical re-equipment) and in the safety substantiation of the hazardous production facility: the organisation that developed the models, calculation methods and computer programs; the adopted calculation models; the values of the main initial data; literature references to the materials used, including information on the verification (certification) of the computer programs, including foreign ones, comparison with other models and with actual data on the investigation of accidents and on experiments; data on the practical use of the methods and computer programs, including foreign ones, for other similar facilities.
346. The procedure for organising and carrying out work on the maintenance and repair of process equipment shall be defined in the regulatory and technical documents of the operating organisation (standards, regulations, instructions, process charts) on the maintenance and repair of process equipment and technical devices, taking into account the conditions of their operation, the assessment of the probability and consequences of failure, the requirements of the regulatory documents and the manufacturers' instructions.
347. The repair of process equipment shall be carried out both when the process facilities (installations) are fully shut down and during their operation, depending on the type of equipment, the availability of a reserve, the duration of the run between repairs and the type and scope of the repair (including when eliminating detected malfunctions). The duration of operation of the process facilities (installations) between shutdowns for the repair of equipment and technical devices shall be established by the regulatory and technical documents of the operating organisation (standards, regulations, instructions, process charts) in accordance with the requirements of the documentation of the equipment manufacturers.
348. The repair of individual types of equipment at installations with process units of any explosion-hazard category under the conditions of an operating production facility shall be carried out in accordance with the instructions on the organisation of the safe conduct of repair work developed and approved by the operating organisation.
349. Equipment shall be prepared for repair by the process personnel and handed over to the person in charge of the repair work, with an entry in the log or in the certificate of handing over the equipment for repair regarding the preparatory work and actions performed, with the issue of a permit to work. The log may be kept in electronic form without duplication on paper, provided that conditions are ensured which preclude the possibility of the unauthorised alteration of the information in the log, and that the electronic signature of the responsible persons is used in accordance with the procedure established by Federal Law No. 63-FZ of 6 April 2011 "On Electronic Signature" (Collection of Legislation of the Russian Federation, 2011, No. 15, Article 2036; 2020, No. 24, Article 3755).
350. The procedure for preparing equipment for repair, issuing the permit to work, handing over for repair and accepting equipment from repair shall be carried out in accordance with the requirements of the instructions (standard, regulation, process chart) on the preparation of equipment for repair and the safe conduct of repair work, developed for each process facility (workshop, installation) or group of facilities and approved by the operating organisation.
351. Materials and articles used in the repair of equipment and technical devices shall be subject to incoming inspection. The procedure for conducting and the scope of the incoming inspection of materials and articles for the repair of equipment and technical devices shall be established in the regulatory documents of the operating organisation (standards, regulations, instructions). When conducting the incoming inspection, the presence of accompanying documents certifying the quality of the products and articles (completeness, packaging, marking, appearance) shall be checked.
352. Gas-hazardous work associated with the preparation of equipment for repair and with carrying out the repair shall be performed in accordance with the instructions on the organisation of the safe conduct of gas-hazardous work developed and approved by the operating organisation.
353. Repair work involving the use of an open flame shall be performed in accordance with the instructions on the organisation of the safe conduct of hot work developed and approved by the operating organisation.
354. During the repair of the equipment of process units of any explosion-hazard category, operation-by-operation quality control of the repair work, including using technical diagnostic methods, as well as comprehensive or individual tests (pressure testing, running-in), shall be carried out. The results of the control and tests shall be reflected in the relevant as-built and reporting documents. Where the tests (pressure testing, running-in) of the equipment produce positive results and the as-built documentation complies with the regulatory requirements, an assessment of the quality of the repair for each unit of equipment and its start-up into further operation are carried out.
355. The assessment of the quality of the repair of equipment (except for maintenance and current repair) shall be determined by the customer and the contractor of the repair, taking into account the requirements of the regulatory and technical documents, and shall be indicated in the handover-and-acceptance certificate for equipment from repair.
356. Repaired equipment may be put into operation where there is a positive assessment of the quality of the repair in the handover-and-acceptance certificate for equipment from repair and where the indicators of the technical parameters (the permitted pressure in the apparatus, the capacity and head of the compressor or pump) and the reliability indicators correspond to the passport data, and where the operating mode established for the given equipment is ensured.
357. A facility (unit, installation) the repair of which has been completed shall be accepted by certificate and permitted for operation after checking the assembly of the process flow diagram, the removal of blanks, the tightness testing of the systems, the verification of the operability of the monitoring, signalling, control and PAZ systems, the effectiveness and response time of the inter-unit shut-off (cut-off) devices, the presence and serviceable condition of the flame-arresting means and the safety devices, the conformity of the installed electrical equipment to the requirements of the regulatory and technical documents on the installation of electrical installations, and the serviceable condition and required efficiency of the ventilation systems. The completeness and quality of the as-built repair documentation, the condition of the facility's territory and workplaces, the readiness of the operating personnel to perform their main duties and other requirements provided for by the regulatory and technical documentation shall be checked. The certificate of acceptance of the facility from repair, authorising its start-up into operation, is approved by the operating organisation.
358. The decision to take a facility (unit, installation) out of operation for a long period and to put these facilities (units, installations) into operation after long shutdowns is taken by the operating organisation. For the period of the long shutdown of a facility (unit, installation), the operating organisation shall provide for a set of organisational and technical measures ensuring: industrial safety during the shutdown of the facility (unit, installation); the physical preservation of the facility (unit, installation); the prevention of its destruction, including as a result of corrosion, and also its operability after the facilities (units, installations) are put into operation.
359. Work with pyrophoric compounds is classified as hazardous work and, on the basis of the conditions of its performance, shall be carried out under a permit to work for gas-hazardous (hot) work in accordance with the procedure established by the operating organisation.
360. The procedure for the safe conduct of work on the cleaning and deactivation of pyrophoric deposits and the inspection and repair of such equipment shall be set out in a separate instruction developed and approved by the operating organisation.
361. Before inspection and repair, vessels and apparatus shall be steamed and washed with water to prevent the spontaneous combustion of pyrophoric deposits. When deactivating pyrophoric compounds, specially developed actions shall be carried out using foam systems based on surface-active agents or other methods, with the washing of the walls of the apparatus free of these compounds.
362. To avoid the self-heating of pyrophoric deposits during repair work, all the assemblies and parts of the process equipment being dismantled shall be kept in a moist state.
363. The supply of steam shall be carried out at such an intensity that a pressure slightly above atmospheric is maintained at all times in the vessels and apparatus. The steam consumption shall be monitored by its exit from the upper part of the vessel, tank or apparatus.
364. The duration of the steaming is established by the relevant instructions for each equipment size individually, but shall be not less than 24 hours. The steaming of apparatus shall be carried out with the hatches closed, and of tanks - with the breather valve open.
365. At the end of the steaming period, measures and means for the deactivation of pyrophoric compounds shall be provided for. Upon completion of the steaming, the equipment shall be filled with water to the top level. After filling, to ensure the slow oxidation of the pyrophoric deposits, the water level shall be lowered at a rate of not more than 0.5 metres per hour.
366. At a below-zero ambient air temperature, the washing (filling) of the equipment shall be carried out with heated water.
367. For the washing and steaming of equipment, stationary or mobile standard devices and communications for the supply of steam and water shall be provided for.
368. Upon completion of the washing, the equipment shall be ventilated (initially with a small supply of steam). The hatches for ventilating the equipment shall be opened starting from the upper one, so as to avoid the intensive movement of atmospheric air within it.
369. Work on cleaning equipment free of pyrophoric deposits carried out by a mechanised method (for example, through the lower manhole using a scraper with intake and suction devices) that does not require the presence of workers inside the equipment may be carried out in accordance with a special instruction approved by the operating organisation. In doing so, the equipment being freed of the combustible product is disconnected from all pipelines by blanks, the internal space is filled with air-mechanical foam of medium or high expansion ratio, and during the performance of the cleaning work the constancy of the filling of the equipment with foam is maintained. When performing the work, conditions shall be ensured that preclude the occurrence of a static electricity discharge.
370. The deposits extracted from the equipment shall be kept under a layer of water or in a moist state in special containers installed away from the places of the possible release and accumulation of combustible vapours and gases.
371. Upon completion of the cleaning of the equipment, the pyrophoric deposits shall be removed from the facility's territory in a moist state to a place specially designated for this purpose or shall be subject to disposal.
The hazard analysis of processes, the quantitative risk assessment and other methods of hazard analysis and risk assessment are a constituent part of the declaration of industrial safety, the safety substantiation of the hazardous production facility, risk management and the industrial safety management system at the hazardous production facility.
Hazard analysis of processes means the methodology of qualitative hazard analysis applied to investigate the possible causes of accidents and incidents, the hazards of failures of technical devices and deviations of process parameters from the regulated ones, and to develop measures to prevent accidents and incidents.
The main methods of hazard analysis of processes are:
2) the hazard and operability analysis method (hereinafter - HAZOP).
These methods are used to substantiate engineering solutions, in the development of operational (where necessary) and design documentation for construction and reconstruction, of documentation for technical re-equipment, capital repair, mothballing and liquidation of the hazardous production facility or a constituent part thereof. The results of the analysis of the engineering solutions adopted by a group of specialists of various profiles (representatives of the design, independent expert and operating organisations) are drawn up in the form of a report. The report is drawn up with an indication of the date and the composition of the participants of the meetings at which the analysis was carried out, of the methodology of the hazard analysis, with a description of the object being analysed, the hazards, the possible causes and consequences of failures of technical devices, deviations of the parameters of the processes from the design or regulated values and other risk factors, and also with an indication of the protective measures and recommendations for reducing the risk of accidents.
The hazard identification method (or preliminary hazard analysis) is based on the analysis of a list of the undesirable consequences of possible accidents and incidents and is most effective for the preliminary identification and description of hazards at the initial stage of design, when selecting the optimum options for the location of the production site, the siting of process facilities and the layout of installations and equipment.
The application of the HAZOP method is preferable at the intermediate and final stages of the development of the design, at which the main structural and technological solutions are worked out. The HAZOP method investigates the hazards of failures of technical devices and of deviations of process parameters (temperature, pressure, composition of the material medium) from the regulated modes.
When characterising a deviation, key words and their combinations are used: "no", "more", "less", "as well as", "other", "other than", "reverse", "pressure", "temperature", "composition", "maintenance", "failure". The use of key words helps the performers to identify all the possible deviations. The specific combination of these words with the process parameters is determined by the specifics of the facility under consideration.
In the process of investigation by the HAZOP method, working tables are drawn up for each part of the process system (object) considered. The tables reflect the results of the work on identifying all the deviations from the design operating mode of the process system (object), the possible consequences of a deviation, the protective measures and recommendations for adopting engineering solutions during design or for the further investigation of the identified problem.
When considering a deviation, the priority or level of criticality of the deviations (high, medium, low) is established, which determines the promptness, form and time frame for implementing the recommendations, including in the development of:
the design documentation of the hazardous production facility (the documentation for technical re-equipment of the hazardous production facility);
the working documentation (before the start of construction of the facility);
the operational documentation (before the facility is put into operation).
LCLFP - the lower concentration limit of flame propagation of a combustible mixture.
The designation of a parameter-symbol with a single prime corresponds to the vapour-gas states of the medium, with a double prime - to liquid media; for example, G' and G" - respectively the mass of the vapour-gas phase (VGP) and of the liquid phase (LP).
E - the total energy potential of explosion hazard (the full combustion energy of the VGP that has entered the environment in the event of an emergency unit depressurisation (ARB), plus the energy of adiabatic expansion of the VGP contained in the unit);
Ep - the full energy released during the combustion of the mass of the LP that has not evaporated in the event of an ARB;
- the combustion energy, in the event of an ARB, of the VGP directly present in the unit and entering it from adjacent apparatus and pipelines;
- the combustion energy of the VGP formed, in the event of an ARB, from the LP present in the unit and entering it from adjacent apparatus and pipelines;
A, Ai - the energy of the compressed VGP contained directly in the unit and entering from adjacent units, regarded as the work of its adiabatic expansion in the event of an ARB;
V', V" - respectively the geometric volumes of the VGP and the LP in the system, unit;
- the volume of the VGP reduced to normal conditions (T0 = 293 K, P0 = 0.1 MPa);
P, P0 - respectively the regulated absolute and the atmospheric (0.1 MPa) pressures in the unit;
- the specific volume of the VGP (under actual conditions);
- the mass of the VGP and the LP present directly in the unit and having entered it, in the event of an ARB, from adjacent facilities;
- the mass of the LP that has evaporated on account of the superheat energy and has entered the environment in the event of an ARB;
q', q" - the specific heat of combustion of the VGP and the LP respectively;
- the total thermal effect of the chemical reaction;
T - the absolute temperature of the medium: the VGP or the LP;
T0, T1 - the absolute normal and regulated temperatures of the VGP or the LP of the unit, K (T0 = 293 K);
t, t0 - the regulated and normal temperatures of the VGP and the LP of the unit (t0 = 20 °C);
- the boiling temperature of the combustible liquid (K or °C);
- the outflow rate of the VGP and the LP into the unit under consideration from adjacent units;
Si - the cross-sectional area through which the outflow of the VGP or the LP is possible in the event of an ARB;
- the rate of heat inflow to the combustible liquid on account of the total thermal effect of the exothermic reaction;
- the rate of heat inflow to the LP from external heat carriers;
K - the heat transfer coefficient from the heat carrier to the combustible liquid;
- the temperature difference of the heat carriers during heat transfer (through the wall);
r - the specific heat of vaporisation of the combustible liquid;
- dimensionless coefficients taking into account the pressure (P) and the adiabatic index (k) of the VGP of the unit;
- a dimensionless coefficient taking into account the hydrodynamics of the flow;
- the density of the VGP or the LP under normal conditions (P = 0.1 MPa and t0 = 20 °C), averaged over the unit and over the i-th flows entering it in the event of an ARB;
- the time from the moment of the ARB until the full actuation of the fittings shutting off the emergency unit;
- the time from the moment of the ARB until the full cessation of the exothermic processes;
- the time from the moment of the ARB until the full cessation of the supply of the heat carrier to the emergency unit (cessation of the heat-exchange process);
- the temperature difference of the LP under the regulated mode and at its boiling at atmospheric pressure;
- the mass of the LP that has evaporated on account of the heat inflow from a solid surface (floor, pan, bund, etc.);
- the mass of the LP that has evaporated on account of the heat transfer from the ambient air to the spilled liquid (over the evaporation surface);
- the total mass of the LP that has evaporated on account of the heat inflow from the environment;
Fzh - the surface area of the liquid mirror;
Fp - the contact area of the liquid with the solid surface of the spill (the area of heat exchange between the spilled liquid and the solid surface);
- the coefficient of thermal activity of the surface (pan);
- the thermal conductivity coefficient of the material of the solid surface (floor, pan, ground, etc.);
cT - the specific heat capacity of the material of the solid surface;
- the density of the material of the solid surface;
Pn - the saturated vapour pressure at the design temperature;
- the contact time of the liquid with the spill surface, taken into account in the calculation.
1. The explosion hazard energy potential E (kJ) of a unit is determined by the total combustion energy of the vapour-gas phase present in the unit, taking into account the magnitude of the work of its adiabatic expansion, and also the magnitude of the total combustion energy of the liquid that has evaporated from the maximum possible area of its spill; the following is assumed: 1) upon emergency depressurisation of an apparatus, its complete opening (destruction) occurs; 2) the liquid spill area is determined on the basis of the design solutions of the buildings or of the outdoor installation site; 3) the evaporation time (the contact time of the liquid with the spill surface taken into account in the calculation) is determined by formula (15) of this Appendix, but not less than 15 minutes and not more than 60 minutes: 1.1. - the sum of the energies of adiabatic expansion A (kJ) and of combustion of the VGP present in the unit, kJ: For the practical determination of the adiabatic expansion energy of the VGP, the following formula may be used: where where At excess values of P < 0.07 MPa and PV' < 0.02 MPa·m3, the adiabatic expansion energy of the VGP (A), owing to its small values, need not be taken into account in the calculation. For multicomponent media, the values of mass and volume are determined taking into account the percentage content and physical properties of the products making up this mixture, or from the single component constituting the largest fraction in it. 1.2. the combustion energy of the VGP that has flowed to the depressurised section from adjacent facilities (units), kJ: For the i-th flow where at excess P ≤ 0.07 MPa 1.3. - the combustion energy of the VGP formed on account of the energy of the superheated LP of the unit under consideration and that has flowed in from adjacent facilities during time , kJ: The quantity of LP that has flowed in from adjacent units: where - depending on the actual properties of the LP and the hydraulic conditions, is taken within the range 0.4 - 0.8; - the excess discharge pressure of the LP. In calculating the discharge velocities of the VGP and LP from adjacent systems into the emergency unit, other calculation formulas that take into account the actual conditions of the operating production, including the hydraulic resistance of the systems from which discharge is possible, may also be used. 1.4. - the combustion energy of the VGP formed from the LP on account of the heat of exothermic reactions that do not cease upon depressurisation, kJ: where - is taken for each case on the basis of the specific regulated conditions of the process and the response time of the shut-off valves and the automatic emergency protection equipment, s. 1.5. - the combustion energy of the VGP formed from the LP on account of the heat inflow from external heat carriers, kJ: The value (kJ/s) may be determined taking into account the specific heat-exchange equipment and the fundamental regularities of heat-exchange processes () from the difference in the heat content of the heat carrier at the inlet to the heat-exchange element (apparatus) and at the outlet from it: where - the per-second flow rate of the heating heat carrier; - the specific heat of vaporisation of the heat carrier, and also by other existing methods. 1.6. - the combustion energy of the VGP formed from LP spilled onto a solid surface (floor, pan, ground, etc.) on account of heat and mass exchange with the surrounding environment (with the underlying surface and the air), kJ: where here T0 the temperature of the underlying surface (floor, pan, ground, etc.), K; where where PN - the saturated vapour pressure at the design temperature Tr, taken as the maximum of the two temperatures - the air temperature and the temperature of the liquid in the spill, kPa. The value of the dimensionless coefficient , taking into account the influence of the velocity and temperature of the air flow over the surface (the evaporation surface) of the liquid, is taken from Table No. 1.
For wind velocities greater than 1 m/s, the value is taken as equal to that at 1 m/s; at an air temperature toc over the evaporation surface greater than 35 °C, the value is taken as equal to that at toc = 35 °C; at an air temperature toc over the evaporation surface less than 10 °C, the value is taken as equal to that at toc = 10 °C.
The evaporation time (the contact time of the liquid with the spill surface taken into account in the calculation) is taken as equal to the maximum value by comparing two quantities - the characteristic time of formation of the explosive cloud (the time to reach the maximum mass within the explosive limits) and the characteristic time of cloud formation for boiling liquids (this quantity is taken as equal to three times the time for equalisation of the boiling and evaporation rates on account of the action of the wind) by the formula:
where: L0.5LFL - the distance at which the VGP drifting from a spill of area Fzh and with an emission rate mi (calculated by formula (14)) disperses to a concentration of 0.5 LFL, m, measured from the windward side, m;
Uvetra - the velocity of the air flow over the evaporation surface, taken as equal to 1 m/s.
Approximately, the value may be determined from Table No. 2.
2. From the values of the total explosion hazard energy potentials E, the values of the reduced mass and of the relative energy potential characterising the explosion hazard of the process units are determined. 2.1. The total mass of combustible vapours (gases) of the explosive vapour-gas cloud m, reduced to a single specific combustion energy equal to 46 000 kJ/kg: 2.2. The relative explosion hazard energy potential QB of a process unit is found by the calculation method using the formula From the values of the relative energy potentials QB and the reduced mass of the vapour-gas medium m, the explosion hazard categories of the process units are established. The category indicators are given in Table No. 3.
3. Taking into account the basic principles set out in this appendix, methodologies for calculating and assessing the explosion hazard levels of units for standard process lines or individual processes may be developed.
To justify the safe siting of installations, buildings and structures within the territory of an explosion- and fire-hazardous production facility, the risk of explosion of vapour-gas media and of fuel-air mixtures (hereinafter - FAM) formed upon an emergency release of liquefied hydrocarbon gases, combustible and readily flammable liquids, gas condensate and other hazardous (combustible, flammable) substances shall be analysed. The explosion risk is a measure of hazard characterising the possibility and severity of the consequences of an explosion. The explosion risk assessment is part of the accident risk analysis, including that applied to justify the explosion resistance of buildings and structures at a hazardous production facility.
The results of the calculations of the injury and destruction zones (of the consequences of an explosion) and of the explosion risk indicators shall be applied when selecting technical actions for the explosion protection of facilities and personnel against the shock-wave effect of an explosion of FAM clouds, and also of solid and liquid chemically unstable compounds (peroxide compounds, acetylides, nitro compounds of various classes, tarring products, nitrogen trichloride) capable of exploding without mixing with air.
The calculations of the dimensions of the injury zones upon ignition of hazardous substances shall be carried out by one of two methodologies:
1) a methodology for assessing the injury zones based on the "TNT equivalent" of an explosion of hazardous substances;
2) a methodology taking into account the type of explosive transformation (detonation/deflagration) upon ignition of the FAM.
The calculation of the injury zones for explosions of solid and liquid chemically unstable compounds, and also for the approximate calculation of the consequences of an FAM explosion within enclosed volumes (rooms), shall be carried out in accordance with the methodology based on the "TNT equivalent".
The calculations of the injury zones for FAM explosions at outdoor installations shall be carried out in accordance with the methodologies taking into account the dispersion (drift) of the FAM clouds and the type of explosive transformation (detonation/deflagration) upon ignition of the FAM.
Sources of ignition of the FAM may be permanent (furnaces, flares, non-explosion-proof electrical equipment) or accidental (temporary hot work, vehicles).
For a more accurate calculation of the consequences of an explosion, including a physical explosion, methods of numerical modelling (computational gas dynamics) shall be used.
1. Methodology for assessing the injury zones based on the "TNT equivalent" of an explosion of hazardous substances 1.1. To assess the level of the impact of an explosion, the "TNT equivalent" of the explosion WT (kg) may be applied, determined from the conditions of adequacy of the nature and degree of destruction in explosions involving other substances and mixtures. The calculation is carried out by the formula: where: Wk - the mass of the solid and liquid chemically unstable compounds, determined from their content in the process system, unit or apparatus, kg; qk - the specific explosion energy of the solid and liquid chemically unstable compounds, kJ/kg; qT - the specific explosion energy of trinitrotoluene (hereinafter - TNT), kJ/kg. 1.2. For the calculation of the consequences of an FAM explosion by the "TNT equivalent" within enclosed volumes (rooms), m' - the reduced mass of the combustible (vapour-gas) substances participating in the explosion - shall be taken into account: m' = zm, (2) where: z - the fraction of the reduced mass of the vapour-gas substances participating in the explosion, taken in accordance with Table No. 1; m - the mass of combustible vapours (gases), kg, determined by formula (17), in accordance with sub-clause 2.1 of Appendix No. 2 to these Rules. The value m', kg, may also be determined by formula (6) in accordance with sub-clause 2.1 of Appendix No. 3 to these Rules. The "TNT equivalent" of the explosion WT, kg, is calculated by the formula: where: 0.4 - the fraction of the explosion energy of the vapour-gas medium expended directly on the formation of the shock wave; 0.9 - the fraction of the explosion energy of the TNT expended directly on the formation of the shock wave; q' - the specific heat of combustion of the vapour-gas medium, equal to 46 000 kJ/kg; qT - the specific explosion energy of the TNT, kJ/kg.
1.3. The destruction zone is taken to be the area with boundaries defined by the radii R, whose centre is the process unit under consideration or the most probable point of depressurisation of the process system. The boundaries of each zone are characterised by the values of the excess pressures at the front of the incident shock wave and, correspondingly, by the dimensionless coefficient K.
The classification of the destruction zones is given in Table No. 2.
1.4. The radius of the destruction zone, m, is determined in general form by the expression:
where: K - a dimensionless coefficient characterising the impact of the explosion on the facility.
At a vapour mass m of more than 5000 kg, the radius of the destruction zone may be determined by the expression:
2. Methodology taking into account the type of explosive transformation (detonation/deflagration) upon ignition of the FAM 2.1. This methodology takes into account the drift and the type of explosive transformation (detonation/deflagration) upon ignition of the FAM clouds. For the calculations of the destruction zones for FAM explosions, the following relations shall be used. The mass of combustible substance capable of participating in the explosion mr (kg) is determined by integrating the concentration of the combustible substance released during the accident over the space bounded by the surfaces and , by the formula: where: x, y, z - spatial variables; and - surfaces in space at which, respectively, the upper and lower concentration limits are reached; c(x, y, z, t0) - the concentration distribution at the instant of time t0, kg/m3; t0 - the instant of the ignition time, s. If, as a result of the calculation by formula (6), the mass within the explosive limits in the primary cloud turns out to be more than 10 per cent of the total mass of fuel present in the primary cloud, then the mass of fuel within the explosive limits of the primary cloud is taken as equal to 10 per cent of the total mass of fuel present in the primary cloud. The basic parameters of the air shock waves (the excess pressure and the impulse of the pressure wave I) are calculated as a function of the distance to the centre of the cloud (including with account taken of the possible drift of the FAM cloud). To calculate the parameters of the air shock wave at a given distance R from the centre of the cloud in the case of detonation of the FAM cloud, the corresponding dimensionless distance is first calculated by the relation: Rx = R / (E / P0)1/3, (7) where: E - the effective energy content of the FAM, J (E = mrq, where q - the heat of combustion of the fuel in the cloud, mr - the mass of the fuel being burned); P0 - the atmospheric pressure, Pa. When calculating the explosion parameters of a cloud lying on the surface of the ground, the value of the effective energy content is doubled. Next, the dimensionless pressure Px and the dimensionless impulse of the compression phase Ix are calculated. 2.1.1. In the case of detonation of a gaseous FAM cloud, the calculation is carried out by the following formulas: Relations (8) and (9) are valid for values of Rx greater than the value Rx = 0.2 and less than Rx = 50. In the case of Rx < 0.2, the value Px is taken as equal to 18.6, and the value Ix is taken as equal to 0.53. In the case of detonation of a heterogeneous FAM cloud, the calculation is carried out by the following formulas: Relations (10) and (11) are valid for values of Rx greater than the value 0.25. In the case where Rx < 0.25, the value Px is taken as equal to 18, and the value Ix = 0.16. 2.1.2. In the case of a deflagration explosive transformation of the FAM cloud, the velocity of the visible flame front Vr and the expansion ratio of the combustion products are added to the parameters affecting the values of the excess pressure and of the impulse of the positive phase. For gas mixtures, = 7 is taken, and for heterogeneous ones, = 4. To calculate the shock-wave parameters for the deflagration of heterogeneous clouds, the value of the effective energy content of the mixture is multiplied by the coefficient . The value Vr is determined on the basis of the explosive properties of the combustible substance and the congestion of the surrounding space affecting the turbulisation of the flame front. The dimensionless pressure Px1 and the impulse of the compression phase Ix1 are determined by the relations: where C0 - the velocity of sound in air, m/s. The last two expressions are valid for values of Rx greater than the value 0.34; otherwise Rx in relations (12) and (13) is taken as equal to 0.34. Next, the values Px2 and Ix2 are calculated, which correspond to the detonation regime and, for the case of detonation of a gas mixture, are calculated by relations (8), (9), and for detonation of a heterogeneous mixture - by relations (10), (11) (in formulas (8) - (11), the values Px and Ix correspond to the values Px2 and Ix2). The final values of Px and Ix are selected from the conditions: Px = min(Px1, Px2), Ix = min(Ix1, Ix2). (14) After the dimensionless values of the pressure and of the impulse of the compression phase have been determined, the corresponding dimensional values are calculated: I = Ix(P0)2/3E1/3/C0. (16) 2.2. To calculate the conditional probability of the destruction of facilities and the injury of people by shock waves, the probit function is used, the value of which is determined as follows: (a) the probability of damage to the walls of industrial buildings at which restoration of the buildings without their demolition is possible may be assessed by the relation: where the function V1 is determined by the following formula: where: - the excess pressure, Pa; I - the impulse, Pa·s; (b) the probability of destruction of industrial buildings at which the buildings are subject to demolition is assessed by the relations: where the function In explosions of FAM inside tanks, or in the destruction of equipment containing gas under pressure, in the general case the hazard of the scattering of fragments and the subsequent development of the accident accompanied by a "domino effect", with the spread of the accident to neighbouring equipment if it contains hazardous substances, shall be taken into account; (c) the probability of a prolonged loss of controllability in people (a knockdown state) who have fallen within the zone of action of the shock wave in the explosion of an FAM cloud may be assessed from the value of the probit function: where the function where mt - the mass of the body of a living organism, kg; (d) the probability of rupture of the eardrums in people from the level of the pressure difference in the air wave is determined by the formula: The probability of people being thrown by the pressure wave is assessed from the value of the probit function: where the function When probit functions are used, the injury zones where the value of the probit function reaches the value corresponding to a probability of 90 per cent are taken as the zones of 100 per cent injury. The injury zones where the value of the probit function reaches the value corresponding to a probability of 1 per cent are taken as the zones that are safe from the point of view of the effect of the damaging factors. 2.3. To calculate the conditional probability of death of people located in buildings, data on the death of people in the destruction of buildings in explosions and earthquakes are used. On the basis of the type of buildings and the excess pressure of the shock wave, the degree of destruction of production and administrative buildings is assessed. The data are given in Table No. 3. The conditional probability of traumatic injury and death of people is determined from Table No. 4. The data are refined when justified, with an indication of the source of information.
3. Criteria of the explosion resistance of buildings 3.1. The explosion resistance of a building under an external explosion is ensured if the condition is met under which the building is located outside the possible zones of action of the incident shock wave with a pressure amplitude at the front exceeding the limiting pressure for which the building is designed: where: Ppr - the limiting pressure at the front of the incident shock wave for which the building under consideration is designed; - the pressure at the front of the shock wave incident on the building; n - the scenario number (N = 1, 2, ..., N); N - the number of scenarios with an explosion. In the absence of precise data, the value Ppr is determined from Table No. 3 corresponding to the lower value of the mean degree of destruction of the building, taking into account its type. 3.2. In the case of failure to meet condition (22), to justify the explosion resistance the results of the quantitative explosion risk analysis and the criterion according to which the frequency of destruction of the building Rr during a year shall not exceed the permissible value Rdop shall be used: Rr < Rdop. (23) The value Rdop is justified in the design documentation or is taken in accordance with normative methodological documents. The calculation of the building destruction risk Rr is determined by the formula: where: P(j) - the calculated frequency of reaching, in the j-th scenario, the parameters of the incident shock wave leading to the destruction of the building (determined by methods of quantitative risk assessment); G - the number of scenarios in which the conditions of destruction of the building are realised. In assessing the explosion risk, the depressurisation frequencies of standard equipment shall be used in accordance with Tables No. 5 - No. 8. The data are refined when justified, with an indication of the source of information.
The frequencies indicated in Table No. 5 are given for process pipelines not subject to intense vibration, not operating in an aggressive medium, in the absence of erosion, and not subject to cyclic thermal loads.
In the presence of the indicated factors, the frequency increases by a factor of 3 - 10 depending on the specifics of the conditions.
Depressurisation at flanged connections is added to the depressurisations on pipelines. One flanged connection is equated, in terms of depressurisation frequency, to 10 metres of pipeline.
The length of the pipeline is not less than 10 metres. At a shorter length, it is taken as equal to 10 metres.
The depressurisation frequency of pressure vessels is reduced if, in the manufacture of the vessel, special technical solutions ensuring a reduction in the accident rate have been used; however, the frequency of complete depressurisation (instantaneous release (C1)) may not be lower than 1 · 10-7 1/year.
The depressurisation frequency of pressure vessels is increased if the usual conditions for ensuring the integrity of the vessel are not met, or if there are other circumstances leading to an increase in the frequency.
If external effects cannot be excluded, then the value of the frequency of complete destruction is increased by 1 · 10-5 1/year for an instantaneous release (C1).