Halon dumps: a data point

From: CLASSICCMP_at_trailing-edge.com <(CLASSICCMP_at_trailing-edge.com)>
Date: Wed Sep 13 19:42:36 2000

A couple years ago we had a thread about Halon fire-suppressing systems
used in computer rooms. Through the school of hard knocks,
I just learned first hand how such systems operate.

Today at work (let's just call it a "large employer in the Washington
DC area") we had a memorable incident in Operations Control when
someone (with undoubtedly good intentions) unscrewed the
solenoid controlling the valve and dumped - without warning -
2500 pounds of Halon 1301 into the room in just a few
seconds. (Operations is a *big* room. It was fitted with eight
giant red tanks of Halon.)

Normally there'd be a thirty-second delay as an audible alarm
allowed the occupants to clear the room, but this feature is
bypassed if you go straight to the solenoid!

The sudden pressure from the halon dump sent numerous ceiling
tiles flying, as well as large stacks of paper that were blown off the
consoles. Not everyone evacuated immediately - several folks
in safety-critical roles stuck around for ten or fifteen minutes
until the firefighters showed up with air packs that allowed others
to relieve them. Some who did stick around eventually left
in ambulances (I *hope* just to run some precautionary tests.)

The good news: the computers didn't hiccup at all during all this.

Moderately good news: Halon dumps aren't instantly fatal.
Seeing as how I spend a good fraction of my day within a couple
of feet of some giant red Halon tanks in the concrete bunker -
oops, officially it's called "computer room" - this is good to know.
I'd been heavily trained that when the Halon dump alarm sounds, you
*get out*. Now I know a little more, especially about the dead-man
switch you can use to delay an electronically-triggered dump.

This Halon is Good Stuff. Other than some grit blasted from the
ceiling tiles, there was zero debris left in the machinery.
What's the "environmentally friendly" equivalent used today?
Is there such an equivalent - something that will put out a fire,
but at the same time not damage vital equipment?

Tim.
Received on Wed Sep 13 2000 - 19:42:36 BST