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Introduction.


pdf icon Introduction. (29 K)
Gann, R. G.

NIST SP 890; Volume 1; 789 p. November 1995.

Fire Suppression System Performance of Alternative Agents in Aircraft Engine and Dry Bay Laboratory Simulations. Volume 1., Gann, R. G., Editor(s), 1-5 pp, 1995.

Available from:

National Technical Information Service
Order number: PB96-117775

Keywords:

fire suppression; aircraft engines; nacelle fires; simulation; halon 1301; halon alternatives; ultraviolet radiation

Abstract:

In a remarkably short period of time, the world has identified, responded to, and ameliorated a new threat to the global climate (WMO, 1995). Following a mechanism first proposed by Rowland and Molina in 1974, chemically stable chlorine-, bromine-, and iodine-containing molecules rise to the stratosphere and are quantitatively photodissociated by ultraviolet radiation. The halogen atoms then catalytically convert ozone (O3) molecules, whose chemistry shields the earth's surface from excess ultraviolet radiation, into oxygen (O2) molecules, which have no such filtration effect. The evidence supporting this hypothesis soon became substantial, and the international political community produced a landmark agreement in 1987, the "Montreal Protocol on Substances That Deplete the Ozone Layer". Subsequent international amendments to this and, domestically, the U.S. Clean Air Act of 1990 have led to restrictions on both production and use of identified ozone-depleting substances (ODSs).