Bench-scale assessment of combustion toxicity—A critical analysis of current protocols

Abstract

The toxicity of fire effluents is not a material property but a function of both the material and the fire environment. To be meaningful, it is essential that toxicity results should relate to the end-use fire situation. This paper reviews current fire effluent toxicity tests, their relevance to fire, and the ways of assessing and applying their results to reduce fire hazards. There are a large number of different methods for determination of the toxic potency of fire effluents from materials or products. These different methods yield apparently inconsistent data because they represent different fire scenarios; measure product yields either as a function of material flammability or independent of it; base the toxicity assessment on the concentrations of different species; or use animal exposure to generate an overall estimate of toxic potency without knowledge of the relative contributions of the chemical species. The drive for internationally harmonised methods for assessment of combustion toxicity, through adoption of international standards, such as those of ISO, provides the framework for meaningful and appropriate use of toxic potency data in the assessment of fire hazard. As structures and means of transportation become larger and more complex, there is movement away from the more traditional methods of ensuring fire safety by prescriptive codes, towards fire risk assessments and engineering solutions. Reliable rate of heat release, fire effluent toxicity and smoke generation data are all essential elements of such an assessment.