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Analysis of the Influence of Piston Effect on Elevator Smoke Control



J H. Klote


This paper is part of a joint project between the United States and Canada to evaluate the feasibility of using elevators for the evacuation of the handicapped during a fire. The transient pressures produced when an elevator car move in a shaft are a potential problem for elevator smoke control. Such piston effect can pull smoke into a normally pressurized elevator lobby. This paper presents an analysis of an elevator smoke control system emphasizing the influence of piston effect on system performance. For most elevators the problem can be overcome by designs that prevent smoke from being pulled into lobbies, and equations for the amount of pressurization air to accomplish this are developed for two arrangements of supply air outlets. Where this approach is not feasible, the methods of analysis presented in this paper can be used to determine smoke infiltration for a hazard analysis.
Special Publication (NIST SP) - 983
Report Number


smoke control, elevators (lifts), hazard analysis, piston effect, pressurization, smoke


Klote, J. (1988), Analysis of the Influence of Piston Effect on Elevator Smoke Control, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 21, 2024)
Created April 1, 1988, Updated June 2, 2021