Do plastic pipes for building water supply need fire arrestors?

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I believe many people find this topic dismissive; they’ve never heard that fire arrestors are needed for plastic water pipes. But the author recently realized that if this question is answered, many concepts will suddenly become clear. A flame arrestor is a fire protection device used to prevent fires from spreading along pipes, and it consists mainly of a metal casing and an internal flame-retardant expanding material. When a fire breaks out, the material inside the fire arrestor expands rapidly, squeezing the pipe and sealing off the openings, thereby effectively preventing the spread of fire and smoke. According to clause 5.2.4 of the \"Code for Acceptance of Construction Quality of Building Water Supply, Drainage and Heating Engineering\" GB50242-2002, fire arrestors or fire-resistant sleeves shall be installed in plastic drainage pipes that are exposed in high-rise buildings, as required by the design. According to 4.4.10 of the \"Code for Design of Building Water Supply and Drainage Systems\" GB50015-2019, the gaps at openings through floors and fire walls, as well as the gaps in sleeves used for metal drainage pipes, should be sealed with fire-resistant materials. The installation of fire arrestors in plastic drainage pipes shall comply with the following provisions: When the pipe passes through a fire wall, fire arrestors shall be installed on the pipes on both sides of the wall ； In high-rise buildings, when drainage risers with a diameter of DN110 or larger are installed explicitly and pass through the floor slabs, installations should be provided on the pipes located on the underside of the floor slabs ； When the drainage pipe passes through the pipe shaft wall, it should be installed on the pipe outside the shaft wall. The standard only specifies plastic drainage pipes. Metal pipes possess a certain degree of fire resistance, and generally, fire or smoke does not spread along them. Therefore, for both water supply and drainage metal pipes, there is no need to consider fire arrestors, aside from using sleeves and fire seals. For plastic water supply pipes, the flow inside the pipe is full-flow; in case of a fire, the pipes will not be burned through due to the presence of water. Therefore, water supply plastic pipes also do not require a flame arrestor ring. Drainage pipes do not contain water all the time; therefore, plastic drainage pipes in such situations require fire-blocking devices to prevent the pipes from being burned through in case of a fire, thereby stopping fire or smoke from spreading through the pipes to other areas. By understanding this issue, I not only learned which pipes require flame arresters but also understood the importance of flame arresters.