Chuck_Harbert@arkwright.com wrote:

The reason they don't use Halon any longer is that it damages the ozone
layer (halogenated cloroflorocarbon(hcf)) as a result of the Montreal
Protocol. It was not recomended for deep seated fires in ordinary
combustibles (paper, wood, cellulosic materials) because under long term
exposure to high temps it would breakdown into harmful gases. It was
excellent for electronics, plastics, flam liquids (surface type fires) in a
confined spaces because you could breath while the fire was extinquished.
It worked to interupt the combustion process and did not use up the oxygen.

I work for Factory Mutual and we did the approval and testing of Halon. It
got eliminated with the other hcf's even though it was only .001% of the
cause of the damage (mostly accidental discharges)to the ozone layer. They
have since developed several "acceptable" alternatives, but none are as
effective, and all are much more expensive.

There are a lot of misconceptions out there and this is one of the common
ones.

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