Effectiveness of Halogenated Agents Against Gaseous Explosions and Propellant Fires.
Proc Nat Acad Sci Symp on an Appraisal of Agents 1972 Apr; :257-277
This report summarizes Bureau of Mines studies on the effectiveness of halogenated agents as fire and explosion suppressants and on the limitations of a commercial halon 1301 extinguisher for use as an ignition-quenching device. Halons containing bromine tend to be more effective than those without bromine in inerting hydrocarbon- air mixtures; the halon 1301 requirement for inerting methane-air mixtures was greater than that previously published. Methane-air ignitions in the Bureau's experimental mine were quenched by a commercial halon 1301 extinguisher only when the agent was applied before the fireball diameter exceeded some critical value ( 18 inches). Dispersion experiments revealed that extinguishment failures in the mine tests were attributable to nonuniform agent distribution which resulted in the formation of voids with very low agent concentrations. A practicable concentration of halon 1301 (for example, 10 percent) can inert a small spill of propellant such as aerozine-50 at room temperature against ordinary ignition sources. [however, impracticably high halon concentrations would be required to extinguish an established aerozine-50 pool fire or to inert the maximum vapor concentrations of this propellant possible in a closed chamber.]
Proc. Nat. Acad. Sci. Symp. on an Appraisal of ... Agents, Apr. 11- 12, 1972, PP. 257-277