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Thermal Radiation From Large Pool Fires (NISTIR 6546)



Kevin B. McGrattan, Howard R. Baum, Anthony P. Hamins


In order to protect people and combustible structures from the thermal radiation emitted by a large fire, the Department of Housing and Urban Development (HUD) has established thermal radiation flux levels of 31.5 kW/m2 (10,000 Btu/h/ft2) for buildings and 1.4 kW/m2 (450 Btu/h/ft2) for people as guidelines in determining an "Acceptable Separation Distance" (ASD) from a fire consuming combustible liquids or gases stored in above ground containers. A review by the Building and Fire Research Laboratory at the National Institute of Standards and Technology (NIST) of the 1975 HUD guidelines for thermal radiation flux has revealed that for certain fire scenarios the methodology can produce estimates of radiation flux that are up to an order of magnitude larger than those actually measured in field experiments.
NIST Interagency/Internal Report (NISTIR) - 6546
Report Number


pool fires, thermal radiation


McGrattan, K. , Baum, H. and Hamins, A. (2000), Thermal Radiation From Large Pool Fires (NISTIR 6546), NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 16, 2024)
Created November 1, 2000, Updated November 10, 2018