Fire extinguishers

[quk@isham-research.demon.co.uk (Phil Payne)]

Someone asked me if I'd ever seen a dry powder extinguisher go off,
and the mess it makes.  Oh yes - see below.  My preference for dry
powder is its persistence - CO2 will put out a fuel fire, but it won't
necessarily _stay_ out if there's a local source of ignition, such as
a sparking cable loom.  Watch the Formula 1 marshalls - dry powder.

(Bye the bye - I watched my video of Michael Schumacher's accident
 again the other day.  Five marshalls were at the car within four
 seconds.)

Anyway - off topic as regards quattros, but on topic as regards fire
extinguishers.  This story is no urban legend - I personally watched
it happen and helped clear up the mess.

Back in 1979, a company called Eternit in Berlin had converted all of
its mainframe tapes to 6250bpi when they suddenly got a new requirement
to read the relatively ancient 800bpi standard.  Problem - no budget.

So they asked us (Itel) to supply an old unit.  We sent them a
control unit and two units free of charge, but made a standard charge
for maintenance of the controller and _one_ unit.  Complete and utter
disclaimer (thank heavens) - if anything breaks, all the bits are yours.

One day one of the units suddenly burst into flames.  Real, big flames.

One of the operators (a guy called Alan Boyles) ran to the extinguisher,
flung open the rear door of the unit, and dumped 3kg of dry powder (it's
actually dried blood) into the unit.  Killed the fire.

What happened next was amazing.  The air conditioning picked up the
flying powder and sucked it into the ceiling ducts.  Down in the
basement, the house engineer was just replacing the filters in the air
conditioning.  He'd pulled one set back and wheeled them away, and was
about to roll in the replacements, when: "This white cloud shot past".

It hit the computer room like the CO2 fog in a science fiction movie.
It rose to about a foot from the floor, and then the disk units started
to drop ready.  As each one sucked in a few grams of this stuff, the
filter clogged and the airflow stopped.  Each unit then powered itself
off.  The processors took a bit longer - perhaps a minute or two.

Within five minutes, the whole room was quiet.  A thin layer of white
powder lay everywhere.

It took three days to clear up the mess.  We rolled back a loading bay
door, put up a wooden replacement, and cut five 3" holes in it.  Five
industrial vacuum cleaners were placed outside, with the hoses led into
the computer room, and we Hoovered for 24 hours.  After that, IBM and
Itel replaced the disk unit and processor filters, and then we checked
each disk unit manually for dust ingress.

All for 3kg of dry powder.

--
 Phil Payne
 UK Audi quattro Owners Club
 Phone: 07785 302803   Fax: 0870 0883933