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Safety of Building Occupants, Building Egress

Building Occupant Safety

Historically, building egress systems have evolved in response to specific large loss incidents. Currently, systems are designed around a concept of providing stair capacity for the largest occupant load floor in the building with little or no consideration of occupant behavior, needs of emergency responders, or evolving technologies. Aggressive building designs, changing occupant demographics, and consumer demand for more efficient systems have forced egress designs beyond the traditional stairwell-based approaches, with little technical foundation for performance and economic trade-offs. In cooperation with the U.S. General Services Administration and other government and private organizations, NIST is working to establish a technical foundation for egress provisions that eliminates egress design as a contributor to fire deaths and minimizes the total social cost of the provisions. .

Building Occupant Evacuation Data

As part of a program to better understand occupant behavior during building emergencies, the Building and Fire Research Laboratory at the National Institute of Standards and Technology (NIST) has been collecting movement data on stairs during fire drill evacuations of office and residential buildings. These data collections are intended to provide a better understanding of this principal building egress feature and develop a technical foundation for future codes and standards requirements. 

Movement on Stairs During Building Evacuations

Simple Estimates of Building Egress Time

NIST has developed a simple tool that combines estimates of stairwell and elevator egress timing to provide an overall estimate of evacuation from buildings. It is based on methods developed in the Society for Fire Protection Engineers Handbook for egress using stairwells and the work of Klote and Alvord on modeling elevator evacuations.

Simple Estimates of Combined Stairwell / Elevator Egress in Buildings

Download Egress Estimator Software


In addition to the collection of data from building evacuations, NIST is active research on human behavior during emergencies, engineering requirements for safe building egress, and egress modeling. A range of publications are available from this research.

Selected Publications on Building Occupant Safety

Created August 25, 2011, Updated August 25, 2016