According to statistics from relevant departments, among the subway fires that occurred, fires caused by electricity accounted for more than half. However, in electrical fires, because there are relatively more wires and cables in subway buildings, and the underground environment is relatively humid, the commercialization of overhead cables, as well as aging and wire overload, etc., cause fires to be relatively large. Proportional. To a certain extent, the toxic gas emitted by the combustible insulation of wires and cables and the burning of protective materials will directly cause casualties, and will also restrict firefighting. Therefore, for these problems, it is necessary to use flame-retardant and fire-resistant wires and cables in the subway construction process, which can prevent electrical fires from occurring.
Subway cable laying
At present, the most commonly used in subway station construction is ordinary flame-retardant fire-retardant wires and cables, which are relatively simple in production and relatively low-cost. Under the conditions of laying, the cable is burned to control the flame spread in the corresponding range. In this way, it prevents the disaster caused by the fire of the wire and cable and improves the fire protection level of the cable. The flame retardants in electrical fires mainly include aluminum hydroxide, chlorinated paraffin, dioxin and phosphoric acid wax and so on. However, the materials of ordinary flame-retardant cables are cross-linked polyethylene, oil hemp and ethylene-propylene rubber, etc. These materials are relatively easy to burn, except for polyvinyl chloride. When a fire occurs in a subway station, the combustion will release a large amount of toxic gases such as hydrogen chloride, and the damage caused is greater than the harm of the fire itself. Therefore, the application of flame-retardant cable materials can prevent corrosive gases from appearing in the cable during combustion, and only produce a small amount of dense smoke, which also reduces the damage to the equipment and the human body, which is conducive to the follow-up rescue work after the fire. The cost of the insulating layer and protective material of the low-smoke flame-retardant cable is based on polyvinyl chloride resin, and then plasticizers and absorbents, high-efficiency flame retardants and marital inhibitors are added to it, and then passed It is produced by a special process. This material can greatly reduce the release of dense smoke and toxic gases produced by the burning of the material, thereby ensuring the safety of the victims and equipment under the subway. So as to reduce economic losses.