Cleaning computers after fire

[Bill Freeman]

Greg Rundlett writes about computers that have experienced fire stress.

	I have only a few points to make beyone what I've read in
other responses.

	If you do wind up trying to use the old units, don't let a few
months of proper operation make you complacent about frequency of
backups and or mirroring on a new machine.  The chemical environment
may have been corrosive, and may have started, for example, connector
problems, that won't show up for a while.

	A related warning: Corrosive residue can be transfered.  Never
put any parts from the old machines into the new ones.  Don't
temporarily install new parts in the old machines and then put it in
the new ones.  Do any disk copying over the network, or via USB, and
never plug the end of the cable that went into the old box into any
new box.  Ethernet cables that connect to new hardware should be new,
and if they plug into a hub that went through the fire, keep track of
the potentially "contaminated" ends.  A little red nail polish makes a
good marker.




	The troubles with any cleaning strategy begin with choosing a
solvent (DI water is a solvent too).  Your looking for something that
will dissolve the crud, but none of the good stuff.  Sadly, there are
so many different materials in a PC that it's hard to know if even
water is safe.  On the other hand, some of the fire residue can be
really resistant.  Also, dissolved crud may be simply washed INTO
anything porous (some insulation and poorly sealed PWBs, for example).

	If I were going to try to save one of these, I'd start with
compressed air.  Be sure you remove any visible residue, gently
scraping with a soft wooden stick if needed.  Take everything apart
that can easily be reassembled (obviously, don't open HDs).  You CAN
get into the power supplies if you try.  I'd avoid using a liquid
solvent without much better information than you seem to have gotten
here.  And remove and discard all fans before you start, replacing
them with new ones when you think the parts that you are keeping are
as clean as possible.

	Considering the labor involved, and how cheap new stuff is
today, it may well not be worth it.

	Good luck,

							Bill