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Calculating Available Safe Egress Time (ASET)--A Computer Program and User's Guide.



Leonard Y. Cooper, D W. Stroup


In the event of a fire in a building compartment the time available for occupants to safely evacuate the compartment, the Available Safe Egress Time (ASET), depends on the time of fire detection and on the time of the onset of hazardous conditions. In order to estimate these two times a dynamic simulation of the developing fire environment in the compartment is required. Also required are specific criteria for the simultion of detection and onset of hazard. A user oriented computer program which carries out the required simulations and provides estimates for the ASET has been developed. This document provides a listing of the program and a manual for its use. For fire growth in a particular fuel assembly, a single program run can be used to evaluate the ASET from enclosures (which are assumed to contain the fuel assembly) of different heights and areas, and under a variety of different detection and hazard criteria. The program can be used in either an interactive or batch mode. It is written in ANSI Fortran and requires no computer specific subroutines.
NIST Interagency/Internal Report (NISTIR) -


combustion products, compartment fires, egress, fire detection, fire growth, hazard analysis, mathematical models, room fires, smoke movement, tenability limits, occupants


Cooper, L. and Stroup, D. (1982), Calculating Available Safe Egress Time (ASET)--A Computer Program and User's Guide., NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 16, 2024)


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Created September 1, 1982, Updated February 19, 2017