From: Judy Seigel (jseigel@panix.com)
Date: 02/23/03-02:18:38 AM Z
On Sat, 22 Feb 2003, Joe Smigiel wrote:
> ... Is it possible to generate
> lethal hydrogen cyanide gas by mixing glacial acetic acid into potassium
> ferricyanide crystals? Anyone is able to walk into photo stores, buy a
> pound of potassium ferricyanide and a gallon of glacial acetic acid, no
> questions asked. Am I correct in respecting this combination as
It's possible, & I've done it -- accidentally. The problem is I don't
remember WHICH common photo chemicals it was, but could well have been
those two... Certainly I've seen many warnings (since then, this happened
when I was very new in photography) about X & Y... some of the warnings on
this list. I think it's an (any?) acid with the k fe.... It was when I was
doing a lot of toning, mixing & experimenting... I left a tray of whatever
it was to use the next day... and when I took the cover off, got a breath
of it. Very, very bad.
As for glacial acetic alone -- I recall an article in I think it was
Popular Photography describing several incidents of the container
exploding. In one case the person was driving a car when the gallon of
glacial exploded next to him.
But then I've had a demi of pepsi explode on me in a supermarket on a hot
day... I got a small cut from broken glass -- of course better pepsi (coke
even) than acid.
> Several toner formulas call for both ingredients in very dilute
> solutions. But, I see it as a possible (though unlikely) scenario that
> an inexperienced worker could mix the pure acid with the crystals.
> Anyone storing them together? I keep them far apart.
Speaking of which, a friend of mind had a bottle of exploding potassium
ferricyanide -- that is somehow the iron got static electricitied... and
when she opened the bottle the grains flew all around the room. (Yes it
happened, to several people,according to photog. formulary, which had the
energetic crystals).
Speaking of storage, it may be just psychological, but I store acids on
one shelf and alkali's on another on the other side of the room. It makes
me feel better...I've found, meanwhile, that some acids weep... The labels
on the bottle of hydrochloric acid and ALL the bottles around it turn to
powder -- no matter how tightly the lid is on. I've taped up the cap and
it still happens.
> Glacial by itself is quite dangerous. Is there any good reason for it
> to be sold in photo shops?
You remind me to lay in a demi, assuming they will close it off. There
are many formulas which call for glacial, many where you want more
concentration-- not to mention that for carrying & storing you're lugging
a heavy load of WATER with the 28%. That is, if you use any amount of it.
(It's used in a lot of toners and bleaches.)
> I'm appalled sometimes at the lack
> of knowledge photographers with many years experience have with regard
> to the chemistry of photography or general housekeeping in the darkroom.
The knowledge of anything "darkroom" grows dim to absent. I found students
weren't quite sure what was a highlight and what was a shadow. They just
tried different filters until they got a look they liked.
> A general FAQ posted each week to this list outlining potential chemical
> dangers of our processes and methods seems a reasonable way to inform
> newbies and the curious.
It shouldn't come automatically with the same subject line every week... I
don't think "alt-photo reminder" or whatever the title for that would win
the sweeps for everyone reading it... I'd suggest rather that it arrive
when signing up -- and maybe at RARE intervals afterward... with a NEW
title, like "update," & then something else.
> Precisely. Does the photographer wishing to engage in potentially dangerous
> processes not also bear some responsibility to inform him/herself, at least
> of the obvious or common dangers? Can an author not assume at least that
> much common sense in his/her readers, or should ALL relevant safety
> precautions be contained in EVERY published article on photographic
> processes? They all carry some risk - you could choke on hypo crystals, you
> know.
We simply tune out stuff that's on autopilot, or resent it -- it's like
nagging. We also do things we KNOW are dangerous, which is one of our
civil liberties. I don't mean particularly in the darkroom. I mean like
jaywalking, and crossing between moving subway cars. I think of the day I
bought a bag of grapes on the street, and being hungry & thirsty ate some
in the subway -- An old guy sitting on the next bench bawled the hell out
of me for eating fruit that wasn't washed.
Which is to say guidelines are useful if thoughtfully done-- if they're
done as in fear of a lawsuit (as the hazards books seem to be) they're
useless.
Oh, and speaking of mercury, colleague of my husband thought he had some
dread disease, swelling, pain, whatever.... turned out he had mercury
poisoning from eating canned tunafish every day. Canned salmon is safer
-- lower on the food chain.
J.
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