Message-ID: <39BFCA7A.D92F03D1@bellsouth.net>
From: John De Armond
Newsgroups: rec.crafts.glass
Subject: Re: Acid deaths
Date: Wed, 13 Sep 2000 14:42:02 -0400

dennisbrady@my-deja.com wrote:

> The big difference is that with skydiving the risks are pretty obvious.
> Specifically, the probably of an uncomfortably sudden impact with the
> ground.  If you want to just reach the ground from an aircraft, there
> are other options to pick from.  The concern many of us posters have is
> that far too many people are experimenting with HFC because the risks
> are not so obvious and they don't know that there are "other ways to
> reach the ground".  I hope the various comments here have at the least
> make a few more people aware of the hazards.

I watched the last HF fear orgy and now this one with a mixture of
sadness and disgust.  The HF that I've used for the past 35+ years
certainly isn't the demon that people here (who probably have never
actually used it) claim.

The fact is, in the concentration a glass artist would use (I use
35%), the acid is NOT a virulently corrosive substance like the
mineral acids.  It will cause burns, it will cause deep necrosis and
it will cause intense pain from calcium fluoride crystal formation
in the tissue - but only if you leave it in contact with the skin.
One can dip the finger in it (I have, just to see what would
happen), calmly walk over to the sink and rinse it off and suffer NO
EFFECT.  Period.  Strong mineral acid left in contact with the skin
for the same length of time would cause serious burns.

It is a specious and spurious straw man argument to cite what
concentrated HF will do because there is NO use for such acid for
glass work.  This is like trying to terrorize someone into not
enjoying a camp fire because forest fires involve combustion.

If one wants the effects on glass that HF provides, there simply
isn't any substitute.  The perfluoride etch creams come somewhat
close but if one really wants the HF vapor frost, one must use HF.

Use gloves and safety glasses or a face shield, good ventilation or
outdoors, have some neutralizing cream on hand if you must (I don't)
and treat the container as if it contained boiling water.  Pretty
much the same rules of the road for any hazardous material.

Glass people can be amazing.  They use very hazardous materials such
as acetylene and hydrogen, high pressure oxygen, hundreds of pounds
of molten glass, lead, toxic patinas and so on with hardly a second
thought.  Yet they cower on the ground trembling in fear at the mere
mention of HF.  Amazing!!!

John

Message-ID: <39C1CCA5.93AC7845@bellsouth.net>
From: John De Armond
Newsgroups: rec.crafts.glass
Subject: Re: Acid deaths
Date: Fri, 15 Sep 2000 03:15:49 -0400

Sam Gaylord wrote:

> The real problem with HF, is that in lower concentrations, as posted
> by someone who stuck his finger in it, it does not cause immediate
> pain.  If you contact HF with the skin, it may be an hour later
> that you start feeling pain, at which point your only option is a
> painful stay in the local ER.  If you use sensible safety percautions,
> wash off and neutralize any that contacts your skin, follow other
> safety rules, it's not bad.  But it still poses a very POTENTIAL
> hazard.

Not quite.  I've spattered 35% HF on my skin and not noticed it
until it started tingling.  Wash it off and the incident is pretty
much over.  I can recall only once where contact was long enough to
start forming calcium fluoride crystals with the resulting pain that
lasted for awhile.  I certainly did NOT go to the emergency room.
Frankly, a bee sting hurts a lot worse.

OF COURSE the stuff will cause nasty, lingering burns if one
saturates a significant portion of the body with HF and leaves it
there.  If one were to be working with gallons of the stuff, I might
consider that a valid risk.  But for the average artist who might
buy a liter of the stuff and then dispense out a few CC into a
plastic pan to fume a hunk of glass with, get real.  This worst case
scenario that everyone seems to love to parrot just ain't gonna
happen.  Weigh the risk of ANYTHING serious happening with this
quantity of HF against those of getting burned with fire or hot
glass or blowing one's self up with a gas leak or getting shocked in
contact with exposed kiln heating elements.

*** Editorial mode on

What is it with you people?  You parrot these Nth-hand myths about
HF with all the authority one would get from first-hand experience.
I'll lay odds that most of you have never even seen a bottle of the
stuff.  Worse are the regurgitations of horror stories industrial
accidents involving many gallons of highly concentrated HF and
implying some relationship to the stuff we glass people use.  'Bout
like citing a natural gas pipeline explosion as justification for
not using a friggin' bench burner!  This is ridiculous, folks!
Harbor your private phobias if you must but please, let's stick to
the facts when influencing others.

*** Editorial mode off

John