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Fuel Effects on the Extinguishment of Laminar Diffusion Flames by Thermal Agents



William M. Pitts, Rodney A. Bryant


The National Institute of Standards and Technology has been investigating the potential of fire-extinguishing agents that act solely by the extraction of heat from a flame zone, i.e., thermal agents, to serve as replacements for halons. Both detailed chemical-kinetic modeling and experimental characterization have been used to better understand the behavior of thermal agents in extinguishing fires. Most of our earlier work, some of which was discussed during the 1999 and 2000 Halon Options Technical Working Conferences, has focused on methane as a fuel. In order to better understand fuel effects, the studies have been extended to flames fueled by propane. During this presentation we will summarize the experimental and detailed chemical-kinetic modeling results for extinguishment of propane flames by thermal agents and compare the findings with those reported earlier using methane. In this paper, experimental extinguishment measurements and detailed chemical-kinetic modeling investigations are extended to propane diffusion flames. The results are compared with earlier findings for methane flames in order to better understand the role of fuel variations in flame extinguishment behavior.
Special Publication (NIST SP) - 984-4
Report Number


halon alternatives, extinguishment, laminar flames, diffusion flames, combustion, diluent gases, fire extinguishing agents, fuel/air mixtures, fire suppressant, reaction kinetics, temperature effects, halons


Pitts, W. and Bryant, R. (2001), Fuel Effects on the Extinguishment of Laminar Diffusion Flames by Thermal Agents, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed December 3, 2023)
Created April 24, 2001, Updated February 19, 2017