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Simulating the Effects of HVAC Induced Air Flow From Slot Diffusers on Detector Response (NISTIR 5908)



J H. Klote, Glenn P. Forney, William D. Davis, Richard W. Bukowski


Rapid activation of fire protection systems in response to a growing fire is one of the important factors required to provide for life safety and property protection. Airflow due to the heating, ventilating and air conditioning (HVAC) system can significantly modify the flow of smoke along the ceiling and must be taken into consideration when a particular system is designed. At present, the standards used to guide the design of systems contain very little quantitative information concerning the impact of airflow produced by HVAC systems. This project is part of a multi year, International Fire Detection Research Project sponsored by the National Fire Protection Research Foundation (NFPFR), and it describes the results of a series of numerical simulations of smoke movement in response to HVAC flows resulting from slot diffusers, slot returns and rectangular returns. The computer model calculated activation times throughout the fire driven flow field.
NIST Interagency/Internal Report (NISTIR) - 5908
Report Number


heating, ventilation, air conditioning, fire models, smoke detectors


Klote, J. , Forney, G. , Davis, W. and Bukowski, R. (1996), Simulating the Effects of HVAC Induced Air Flow From Slot Diffusers on Detector Response (NISTIR 5908), NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 17, 2024)
Created December 1, 1996, Updated November 10, 2018