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Screening Tests for Alternative Suppressants for In-Flight Aircraft Fires.


pdf icon Screening Tests for Alternative Suppressants for In-Flight Aircraft Fires. (258 K)
Gann, R. G.

HOTWC 2006;

Halon Options Technical Working Conference, 16th Proceedings. HOTWC 2006. May 16-18, 2006, Albuquerque, NM, 1-16 pp, 2006.

Keywords:

halon alternatives; halons; halon 1301; fire suppression; aircraft fires; chemical properties; atmospheric lifetime; effectiveness; toxicity; water; regulations; halocarbons; human beings; exposure

Abstract:

A primary component of the Next Generation Fire Suppression Technology Program (NGP) was the examination of the "world" of chemistry, seeking to identify chemicals that merited examination under practical fire suppression conditions or to enable a finding that no previously unidentified such chemicals existed. Performing this survey required a protocol for rapid and inexpensive screening of literally thousands of chemicals to identify those relatively few agents worthy of further examination as alternative fire suppressants. There are multiple, critical chemical properties whose beneficial values promoted the widespread use of halon 1301 (CF3Br) and which would affect consideration of alternative fire suppressants. These are fire suppression efficiency, quenching of flame re-ignition, ozone depletion potential (ODP), global warming potential (GWP), atmospheric lifetime, suppressant residue, electrical conductivity, corrosivity to metals, compatibility with polymeric materials, stability under long-term storage, toxicity of the chemical and its combustion and decomposition products, and speed of dispersion. Estimation of these values needed to be obtained using minimal mass of the chemicals for cost and toxicity reasons. A testing hierarchy was needed to ensure that the most unique chemicals and the properties that were deemed most important and used the least chemical were determined first. Figures of merit for each property and a testing/estimating sequence and target values were also needed. The NGP built on prior methods used to screen chemicals, an NGP-organized workshop on agent compatibility with people, materials and the environment, and other formal and informal procedures.