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Introduction.


pdf icon Introduction. (1995 K)
Grosshandler, W. L.; Gann, R. G.; Pitts, W. M.

NIST SP 861; April 1994.

Evaluation of Alternative In-Flight Fire Suppressants for Full-Scale Testing in Simulated Aircraft Engine Nacelles and Dry Bays. Section 1, Grosshandler, W. L.; Gann, R. G.; Pitts, W. M., Editor(s)(s), 1-12 pp, 1994.

Available from:

Government Printing Office
Order number: SN003-003-03268-9

Keywords:

halons; ozone; aircraft engines; nacelle fires; simulation; fire suppression; effectiveness; compatibility; fire extinguishing agents; halon alternatives; ultraviolet radiation

Abstract:

The Montreal Protocol of 1987 identified halon 1301 (CF3Br) as one of a number of halogenated chemicals that were sufficiently deleterious to stratospheric ozone that their continued production and use required limitation. An amendment to the Protocol caused commercial halon production to cease at the beginning of 1994. The focus of concern is that the halon molecule is sufficiently stable in the lower atmosphere that it will eventually be transported to the stratosphere unaltered. There the carbon-bromine bond is vulnerable to photodissociation by solar ultraviolet radiation. The liberated bromine atom then enters into a catalytic cycle which has the net effect of consuming the shielding ozone.