A concept for estimating available safe egress time in fires

Abstract

Available Safe Egress Time (ASET) in enclosure fires is defined as the time between fire detection and the onset of conditions which are hazardous to continued human occupancy. A general technique for estimating this time interval is introduced. A description of hazard development is presented. This description identifies the variables of fire growth which are significant to life safety. A conceptual engineering model which simulates these variables is formulated. Because of the primary focus on life safety, as compared with property protection or structural integrity per se, the suggested modeling includes significant simplifying assumptions which would not be otherwise justified. The concepts developed in this paper provide a rational basis for the use of a mathematical model and user oriented computer program, presented in other works, to actually carry out ASET calculations for compartments of fire origin.