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Simulating the Effect of Sloped Beamed Ceilings on Detector and Sprinkler Response (NISTIR 5499)



William D. Davis, Glenn P. Forney, Richard W. Bukowski


The rapid activation of fire detection and suppression systems in response to a growing fire is one of the important factors required to provide for life safety and property protection. Rapid activation requires that sensors be located at optimal distances both beneath the ceiling and radially from the fire. Ceiling obstructions, such as beams and joists, and ceiling slope can significantly modify the flow of smoke along the ceiling and must be taken into consideration when a particular detection system is designed. At present, the standards used to guide the design of these systems contain very little quantitative information concerning the impact of beamed, sloped ceilings on detector placement.
NIST Interagency/Internal Report (NISTIR) - 5499
Report Number


fire research, ceilings, simulation, detector response, sprinkler response, detectors, joists


Davis, W. , Forney, G. and Bukowski, R. (1994), Simulating the Effect of Sloped Beamed Ceilings on Detector and Sprinkler Response (NISTIR 5499), NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 27, 2024)


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Created October 17, 1994, Updated November 10, 2018