How to handle abnormal operating conditions in chemical enterprises? The guidelines are here!

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Notice from the General Office of the Ministry of Emergency Management on Issuing the “Guidelines for Safe Handling of Abnormal Conditions during the Production Process in Chemical Enterprises (Trial)” – Emergency Management Department [2024] No. 17 To the emergency management departments (bureaus) of all provinces, autonomous regions, and municipalities directly under the Central Government, the Emergency Management Bureau of the Xinjiang Production and Construction Corps, and relevant central state-owned enterprises: In order to thoroughly implement the important instructions on work safety issued by *****, to earnestly carry out the decisions and arrangements made by **** and the State Council regarding work safety in the chemical and hazardous chemicals industries, to learn from the lessons of typical accidents, and to effectively prevent and mitigate major safety risks, these “Guidelines for Safe Handling of Abnormal Conditions during the Production Process in Chemical Enterprises (Trial)” (hereinafter referred to as the “Guidelines”) have been approved by the ministerial meeting of the Ministry of Emergency Management and are now issued to you. Please ensure their strict implementation, and the following requirements are put forward: 1. The emergency management departments in various regions and the headquarters of relevant central state-owned enterprises should earnestly implement the three-year action plan aimed at addressing the root causes of safety issues in the chemical and hazardous chemicals industries. They should also strengthen the promotion and training related to these Guidelines, assist enterprises in enhancing their understanding of them, ensuring that they fully comprehend and adhere to the requirements set out in these Guidelines, thereby improving their ability to manage safety risks associated with abnormal conditions during production. II. Emergency management departments in various regions and the headquarters of relevant central state-owned enterprises should organize these enterprises to carefully refer to the \"Disposal Guidelines,\" establish and improve systems for dealing with abnormal operating conditions, standardize the procedures for handling such situations, and enhance the ability to safely manage abnormal conditions during the production process. III. Emergency management departments in various regions should, in conjunction with their routine supervision tasks, strengthen oversight and guidance regarding the safe handling of abnormal conditions during the production process in chemical enterprises, ensure that the relevant requirements for such safe handling are properly implemented, and take strict legal action against any violations to prevent and reduce production safety accidents. General Office of the Ministry of Emergency Management, April 25, 2024 – Guidelines for the Safe Handling of Abnormal Conditions during the Production Process in Chemical Enterprises (Trial) 1. Purpose: These guidelines are formulated to further standardize and strengthen the management of safety risks associated with abnormal conditions during the production process in chemical enterprises, to enhance awareness and capabilities regarding the safe handling of such abnormal conditions, and to guide enterprises in taking scientific and prudent actions to prevent and reduce production safety accidents. 2 Scope of Application These guidelines apply to situations such as the start-up and shutdown of units during the production operation phase in chemical enterprises, unplanned inspections and maintenance, abnormal operating parameters, abnormal operations or equipment failures, as well as other situations involving a risk of accidental release of energy. 3 Basic Requirements 3.1 Enterprises should, in their daily operations, conduct risk assessments by considering abnormal operating conditions, establish or clarify emergency response procedures, and carry out training and drills. 3.2 Emergency response procedures shall include at least: response steps, safety measures, and shutdown conditions. 3.3 During emergency handling, without conducting evaluations and obtaining approvals, the enterprise shall not remove or bypass interlocks in order to force the operation of equipment or devices. 3.4 Enterprises should establish comprehensive authorization mechanisms for personnel on duty to initiate emergency shutdowns and carry out evacuations. 3.5 After the device interlock is triggered, the cause should be identified promptly, and the conditions that trigger the interlock should be eliminated one by one; forced reset is strictly prohibited. 3.6 All alarms from the device must be responded to promptly. After a detection of combustible or toxic gases or an alarm from the fire alarm system, it is strictly prohibited to dismiss the alarm arbitrarily without analyzing the cause and going to the site to verify the situation. 3.7 For operations such as hot work, work in confined spaces, and the opening of equipment or pipelines, enterprises shall obtain the necessary approval in accordance with relevant regulations. 4 Disposal Principles 4.1 Retreat to a safe state promptly 4.1.1 In the following situations, it is necessary to retreat to a safe state in accordance with emergency procedures: (1) When abnormal conditions such as excessive temperature rise in the operating unit, sudden changes in pressure, polymerization explosions, boiling over, pipeline blockages, mixing failure, or severe vibration of the equipment occur. (2) Emergency pressure relief devices such as safety valves and burst discs activate abnormally, with the cause unknown and normal operation unable to be restored. (3) Failures of critical equipment, disruptions to essential utility systems (water, electricity, steam, air), failures in instrument control systems, etc., for which the causes are unknown and normal operation cannot be restored. (4) There is a significant leakage of flammable, explosive, highly toxic, or extremely toxic substances, posing a risk of loss of control. (5) In the event of natural disasters such as earthquakes, typhoons, or heavy rainfall, normal production cannot be ensured. Safe shutdown methods include, but are not limited to: full plant shutdown, partial shutdown, cessation of heating, emergency cooling, stoppage of feed supply, termination of the reaction, unloading for pressure relief, and isolation of the unit. 4.1.2 If the device encounters an abnormal operating condition that was not anticipated in advance and for which there is no emergency response procedure, it should be stopped immediately. 4.2 Minimizing the number of personnel on-site 4.2.1 When the situation on-site is unclear, no one shall enter the site without conducting a safety risk assessment and without taking appropriate safety precautions. Once it is determined that the site can be accessed, up to 2 people wearing the necessary protective equipment, alarm devices, and relevant safety tools may enter the site to conduct further investigations. 4.2.2 During the disposal process, on-site personnel must be strictly controlled, responsibilities must be clearly defined, and the number of workers on site should be kept to a minimum. It is strictly prohibited for personnel unrelated to the disposal process to enter the work area. 4.2.3 During on-site handling, cross-tasking at the same location is generally not permitted; there should usually be 2 people in the same equipment area, with a maximum of 6 people. 4.2.4 Commanders should use devices such as video and radio communication to carry out remote dispatching and command as much as possible. 4.2.5 Information and digital technologies such as video surveillance, electronic fences, and risk monitoring and early warning systems based on personnel positioning should be employed to strengthen the control of risks associated with crowd gathering at the incident site. 4.3 Comprehensive identification and analysis of risks for proper handling 4.3.1 Before taking any action, it is necessary to conduct a thorough analysis of the safety risks associated with the handling process, and to establish effective control measures; it is strictly prohibited to take actions blindly when the risks are unclear or uncontrollable. 4.3.2 When dealing with blockages in pipelines, valves, etc., the method of clearing the blockage should be determined by taking into account factors such as the characteristics of the blocking substance, the design specifications of the equipment and pipelines, and the properties of the medium used for clearing; forceful methods are prohibited. When dealing with obstructions that are highly sensitive to impact, it is strictly prohibited to use external force for striking. 4.3.3 Strictly verify the operational safety conditions; it is strictly prohibited to rely solely on methods such as visual inspection, sniffing, listening, and touching as means to confirm safety conditions. Methods of confirmation include, but are not limited to: (1) Confirmation that pressure relief is complete, such as by observing the movement of the gauge pointer on-site or the pressure variation curve on the DCS, by comparing readings from two or more different pressure monitoring systems, or by slightly opening drain or vent valves based on the hazardous properties of the material. (2) Verification of the effectiveness of energy isolation for containers and pipelines, such as whether blind flanges have been installed as required, whether all vent and drain lines are open, and whether the connecting pipelines have been disconnected. (3) Confirmation that the electrical equipment is de-energized, such as locking and labeling the switchgear after de-energization, conducting on-site tests, using instruments for live inspections, moving the circuit breaker (cabinet) to the maintenance position (test position), opening the disconnect switch, and removing fuses. (4) Before entering a confined space, conduct representative and comprehensive gas testing using testing instruments that meet relevant standards; where possible, use portable detectors as well as laboratory sampling and analysis for confirmation. 4.3.4 The handling personnel shall wear appropriate and effective personal protective equipment, depending on the characteristics of the materials on site and the potential risks. 4.4 Effective prevention of accidental energy release 4.4.1 During maintenance operations that involve the opening of pipelines and equipment, it is necessary to depressurize the areas before and after the sections being disassembled or assembled, purge them, and isolate them physically from the operating system. It is strictly prohibited to use water seals or closed valves as a substitute for installing blind flanges. 4.4.2 During disposal operations, sealing or drilling under pressure should not be carried out unless it is absolutely necessary. Where it is truly necessary during emergency response, the enterprise shall conduct a feasibility assessment of the operations, investigate the conditions of the site and the equipment, and develop a specific operation plan. 4.4.3 Pressurized operations are strictly prohibited on equipment and pipelines handling extremely hazardous toxic media ； Under pressure operations are strictly prohibited in situations where thickness measurement has not been carried out, it is not possible to effectively prevent the further propagation of cracks in the material, the stiffness and strength of the structure and material do not meet safety requirements, or appropriate safeguard measures have not been put in place. 4.5 Global consideration for unified command 4.5.1 In dealing with abnormal operating conditions, it is necessary to take into account the stability of internal and external utility systems of the facility as well as the impact on material balance upstream and downstream; multiple commands or disorderly handling are strictly prohibited. 4.5.2 It should be specified that a dedicated person shall, from the control room and by monitoring the DCS, promptly check the status of upstream and downstream devices as well as the management of on-site safety risks in response to abnormal operating conditions. 4.5.3 After dealing with abnormal operating conditions, it is necessary to promptly analyze the causes of such conditions, and make improvements from both managerial and technical perspectives. This includes refining operational procedures and emergency response plans, as well as organizing regular training sessions for relevant personnel to enhance their ability to handle abnormal situations. 4.5.4 In the event that abnormal operating conditions fall under the scope of the emergency response plan, responses shall be carried out in accordance with the plan’s procedures and measures for handling such situations.