>When we say nearby how nearby are we talking about? Like in the same room
>or just within a few feet?
Same room, garage, basement, drafty shed, or even just nearby
downwind. It's probably the chlorine more than anything else. I've had
the most problem with the translucent jugs of pool acid, while the heavy
white jugs of acid seem to keep it sealed pretty well. Also a problem
with when I've left the etchant uncovered (duh), then it can freely get
loose and rust things, fog optics/glass, ruin anodized finishes, etc.
I recall a post, here or somewhere else, where someone said that
etchant/acid fumes ate the heads off all the nails on the inside of their
shed. I'd expect that to have taken a LOT of fumes and a substantial
period of time.
I'd say that the best place to store etchant would be in a plastic
bottle with the air squeezed out - then there's those ketchup squeeze
bottles again - in a five gallon plastic bucket with a bunch of
neutralizer in the botton as someone mentioned, either baking soda or
sodium carbonate from the pool store, somewhere outside, safe from prying
children.
Of course, that's "best", and I'm sure there's folks who just have
it under the sink with the other more horrible corrosive poisons. Hint:
If you can smell it, it's getting out, and you don't want that.
If you're only working with a half pint or so, go with the squeezed
ketchup bottle and keep it somewhere drafty (if possible), it shouldn't
be a huge deal. I just happen to have a talent for activating Murphy's
Law ("Anything that can go wrong, will go wrong, most likely when
everyone is watching"), that's why I wear shoes and seatbelts.
-Gary