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Flame Suppression Effectiveness (NIST SP 861)



Anthony P. Hamins, G. Gmurczyk, William L. Grosshandler, R. G. Rehwoldt, I Vazquez, Thomas G. Cleary, Cary Presser, K Seshadri


A flame will be extinguished when the time required for the chain reaction which sustains combustion exceeds the time it takes to replenish the necessary heat and reactants. A characteristic time for reaction can be estimated from the inverse of a global kinetic rate coefficient expressed in Arrhenius form as [equation] where B is a molecular collision frequency factor, Eo is a global activation energy, R is the ideal gas constant, and T is the gas temperature. Assuming reactant species and heat are transported at about the same rate (i.e., unity Lewis number), a characteristic time for replenishing both can be estimated from a convective flow velocity and a length scale by [equation].
Special Publication (NIST SP) - 861
Report Number


halons, fire suppression, effectiveness, diffusion flames, turbulent flames, premixed flames, detonation, chain reactions


Hamins, A. , Gmurczyk, G. , Grosshandler, W. , Rehwoldt, R. , Vazquez, I. , Cleary, T. , Presser, C. and Seshadri, K. (1994), Flame Suppression Effectiveness (NIST SP 861), Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 24, 2024)


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Created April 1, 1994, Updated June 2, 2021