Fire performance of poly(vinyl chloride) and its relation to fire hazard

This paper discusses the most important parameters in terms of fire hazard and shows how PVC fares in relation to other polymers. The fire properties specifically addressed are: ignitability, flammability, flame spread, rate and amount of heat release, mass loss rate, smoke release and toxicity. Hydrogen chloride decay is also commented on, because it affects the toxicity of PVC smoke. The individual parameter most relevant to fire hazard is heat release. The two most useful tools for measuring rate of heat release (viz. the OSU and Cone calorimeters) are described. Results obtained from them are discussed. Smoke can best be measured by combined parameters from rate of heat release calorimeters, rather than in the traditional static NBS smoke chamber. Toxic hazard is being addressed by recognition that most smokes are of similar toxicity, so that the mass loss rate will, generally, govern the toxicity of smoke. Not all fire tests are equally good representations of the probable consequences of a full-scale fire. Fire hazard assessment is best carried out based on those test results most relevant to real fires; they can be obtained from small and full-scale experiments and fire models. The fire performance of PVC is excellent; PVC products generally represent low fire hazard in a scenario.