[Corvettaholic]

I want to a couple experiments with nitric acid, but having a thingy full of acid.. its gonna give off fumes that are bad for me, I assume. So for safety, I'm going to work outside in my backyard, is this enough to mitigate the fume hazard? I also have my M40A1 gasmask with a charcoal canister, great against CS gas, but will this offer any fume protection? I got a bunch of questions for this experiment, but I'll post those next week, cause I'm about to take a much needed 3-day rest break!

[jdurg]

Make sure you are upwind from the HNO₃ when you do anything with it.  Nitric acid is really nasty stuff that will turn your skin yellow and leave nasty burns in your flesh.  It also has a nasty tendency to turn organic compounds into things that go boom.  So just be really careful and make sure you have thick gloves on and a face mask.  The gasmask may be a bit of overkill, but I preach the "better safe than sorry" rule.  (I always exaggerate every chemical "incident" I experience since it usually leads to some relaxation when what I thought was really bad turned out to be nothing).  

[Mitch]

Sounds fine. Gas mask is probably overkill, just work so the wind won't spew the fumes over you.

[Corvettaholic]

I don't have goggles or a breathing mask, but I figured my army issue equipment should be fine. Since the thing is rated to protect me from sarin and VX, I figure it should work out fine. I also have my tinted inserts which I guess are supposed to be sunglasses, but they'll work to dampen bright stuff. I really should invest in a welder's mask for future stuff. Also, I'm trying to figure out a good container to use to contain the nitric acid. Glassware works okay? I'm sure I can find some used lab equipment for a good price. I assume my cast iron spaghetti pot won't work.

[hmx9123]

You need to be quite careful when working with nitric acid, especialy if concentrated.  The burns it leaves on the skin are painful but only topical.  The real danger is if you do something stupid like put organics or different metals into it.  Then it releases a lot of NO₂ and that is very toxic (on the 10s-100s ppm level, IIRC).  A gas mask won't do s#*$ for the nitric--nitric acid eats rubber at an astonishing rate, and you'd need a filter specifically for NO₂.  I've got a cylinder of NO₂ gas here, and when I tried to buy a regulator, they told me that I should really just stick with a stainless steel needle valve for two reasons: 1. the pressure of the gas is pretty low and 2. the needle valves were a lot cheaper to replace and the NO₂ would tear both it and a regulator up.

For small quantities, the mask with an NO₂ filter might work out OK, but if you generate a lot of NO₂ on accident, you're going to be in trouble.  It is not recommended that you use nitric acid outside of a decent fume hood.  Outside is not a terribly good idea, especially in an enclosed area.  Upwind will be OK until the wind direction changes.

The only container that will work for you is glass.  Make sure it's Pyrex, too, because if you use soft glass, and you your solution heats up (as it is bound to if you put anything in it) it will have a good chance at cracking.

Also, are you buying nitric acid?  I only know of one place that sells con nitric to the general public, and it's pretty shady.  If you're making your own, then you're in for even more of a NO₂ fume ride.

Of course, the fumes from con nitric alone really suck, so don't breathe them either.

[jdurg]

Yeah, the smell of nitric acid is kind of weird.  It has a bleach-like odor, but it is quite distinctly not bleach.  I guess it's too unique to describe.  It's like trying to tell someone what bleach smells like when they've never smelled it before.  

[Corvettaholic]

Yeah, I'm in no rush to breathe in fumes. I'm gonna leave this idea alone until I'm properly up to spec on safety. Besides, if the fumes ate my gas mask, I'd be in a load of trouble with the army. The nastiest thing I've ever accidentally inhaled was chlorine gas, and it was rather unpleasant.

[Scratch-]

Don’t they use NO₂ to knock people out during operations? Somebody told me that the problem about it is getting enough oxygen to the patient while giving them the NO₂.

[jdurg]

Nope.  They use N₂O.  (Nitrous oxide, not nitric oxide).  If they used nitric oxide, the patient would die shortly after the gas was administered.

Also, the whole issue with the oxygen is the same with any anesthetic.  Anesthesiologists need to make sure that enough anesthetic is administered to knock them out, but enough oxygen is given as well to keep them alive.  When moronic teenagers and college kids try and inhale nitrous oxides from balloons, they will generally give themselves faaaaaaaaaaaaaaar more than is considered safe and that is when problems occur.