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Enhancement of EXIT89 and Analysis of World Trade Center Data



R F. Fahy


The features of an enhanced model for egress from fires in non-residential occupancies is presented along with a users manual describing the use of the model. The enhancements to the model include analysis of locations of safety, smoke blockages, disabled occupants, and delays in egress. Comparisons with some available field measurements is presented. Further analysis of human behavior during a fire in the World Trade Center is presented. The analysis shows that there was a significant difference in perception of the severity of the fire between the two buildings of the World Trade Center. While previous human behavior studies have shown that people will move through smoke, this incident demonstrated that people will not only move through smoke, but also through worsening conditions. Implications for evacuation and training are discussed.
Grant/Contract Reports (NISTGCR) - 95-684
Report Number


computer simulation, egress, field tests, fire models, human behavior, training, occupants, terrorists, terrorism, World Trade Center


Fahy, R. (1996), Enhancement of EXIT89 and Analysis of World Trade Center Data, Grant/Contract Reports (NISTGCR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 20, 2024)


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Created August 1, 1996, Updated February 19, 2017