The objective of fire hazard and risk analyses is to estimate conditions of safety for people, including those that are more sensitive to fire smoke than others. For this purpose, this paper develops a method for estimating, from information on lethal and incapacitating exposures for the median rat, smoke toxic potency values for incapacitation of the smoke-sensitive human. For those engineering applications where the mix of combustibles is unknown, generic values are derived of the concentration of smoke that would incapacitate smoke-sensitive people in 5 min: 6 g/m3 for a well-ventilated fire and 3 g/m3 for a post-flashover fire. These values are estimated with significant assumptions in their derivation, resulting in an estimated uncertainty of about a factor of two. Further, there is a wide range of smoke toxic potency values reported for various combustibles, and some of these will lead to values significantly higher or lower than these generic figures.
Citation: Fire Technology
Pub Type: Journals
fire, incapacitation, lethality, smoke, smoke toxicity