Discussion on the fire separation distance for emergency ponds in chemical engineering construction projects

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Article 6.6.3 of the \"Environmental Protection Design Standards for Chemical Engineering Construction Projects\" GBT 50483–2019: When accident wastewater contains substances of Category A, Category B, or Category C, the fire classification shall be determined as Category C; however, in emergency situations, it shall be managed as if it were of Category A； Article 4.2.8 of the \"Code for Fire Protection Design of Petrochemical Enterprises (2018 Edition)\” GB50160-2008: 4.2.8A Accident water tanks and rainwater monitoring tanks should be located in the lower areas at the edge of the plant site; they can also be arranged together with the sewage treatment facilities. The fire protection distance between the accident tank and open flames should be no less than 25 m, and the fire protection distance from elevated flares that may carry flammable liquids should be no less than 60 m. Explanation of the provisions: The accident tank is primarily used to collect contaminated fire-fighting water under fire conditions, polluted rainwater, and any combustible substances that may leak. Accident water and rainwater generally flow by gravity through pipelines to the accident water tank and the rainwater monitoring tank; therefore, these tanks should be located at lower positions on the edge of the plant area. Accident water and rainwater that fails monitoring tests must be treated to meet standards before being discharged from the plant; locating the treatment facilities together with the sewage treatment plant can reduce pipeline lengths and save energy. Since a fire accident may be accompanied by a leak of flammable liquids, fire separation distances have been specified between the accident tank, open flames, and elevated flares that may carry flammable liquids. Since the accident pool remains empty for long periods of time, no fire separation distance is required from other facilities. GB51283 does not specify clear requirements regarding the fire separation distances for accident ponds. If GB51283 is to be followed, should the fire separation distances be determined based on those for Class C open-type facilities, or for wastewater treatment facilities that contain flammable liquids? Or are no such requirements specified?