Building a small machine room?

Luc Vereecken Luc.Vereecken at
Fri Sep 19 06:57:18 EDT 2003

>At 06:03 AM 9/18/2003 -0700, Andrew Latham wrote:
>>Halon is not banned from telcom rooms so just sell it to the fire marshal
as a
>>telcom room. I was under the impression that the room would have no people
>>permanently stationed in it.
>>Halon does not kill people. It replaces Oxygen. It can injure or kill a
>>after large and lengthy exposure but not likely.

Actually, Halon does not replace oxygen. CO2 extinguishers work by
replacing oxygen, depriving the flames of their oxidant. Halon molecules
(which contain halogen atoms, primarily Bromine) decompose in the flame,
and the Bromine atoms catalyse the recombination of radicals in the flame,
causing the flame to die from a lack of active radicals. This is why you
need clouds of CO2, but only a small percentage of halons (< 0.5% ? ) in
the air to stop a fire. The O2-concentration is hardly affected by this
small amount of halon. 

At 09:22 AM 9/18/03 -0700, Jim Lux wrote:
>Halon is now incredibly expensive and an "ozone depleter", .

Because the bromine atoms, released after decomposition in the stratosphere
by hard radiation, are efficient radical quenchers, they efficiently start
to quench our ozone (O3 radicals). Bummer.  

<preach>Which is why you should never use Halon, even if it would have been
legal to do so, and certainly not use any loopholes in the law to use it
anyway. Putting the entire world population at risk because it is
convenient for yourself is not acceptable. </preach> A number of
alternatives have already been mentioned in other posts. 


Luc Vereecken (who uses his cluster to work on combustion chemistry (-: )

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