[muffaletaman]

Compressed gasses intrigued me, BUT you have to make sure you can get away!

I did a little checking. Having worked in the oil drilling industry, we are concerned with H2S in sour gas wells. I have heard about people just getting a whiff of the gas and passing out immediately.

BUT here is what I found based on MSDS’s about gas toxicity. H2S isn’t so bad.

GAS - OSHA PEL - LC50
H2S - 20 ppm - LC50 444 ppm (rat)
CHLORINE - 1 ppm - LC50 293 ppm / 1 hr (rat)
PHOSGENE - 0.1 ppm - LC50 800 ppm (human)
ARSENIC PENTAFLOURIDE - As 0.01mg/m^3 - LC50 20 ppm / 1 hr (rat)

So maybe forget the gases - stick with the tire iron or shotgun, depending on your situation and skill-set / training...

[yefragetuwrabrumuy]

LD/50s are good for estimating lethality, but it’s a lot harder to judge incapacitation.

I once got a small whiff of chlorine at a public pool and it was pure, unadulterated agony, followed by sucking on an oxygen tank for a long time (no idea how long, as time became very relative.)

But you also need to consider the shock value of a face full of chlorine, along with the ease in which it can be obtained. Just a bit of pool sodium hypochlorite and acid.

“It is estimated that there are about 3300 accidents needing hospital treatment caused by sodium hypochlorite solutions each year in British homes (RoSPA, 2002).”

[Smokin' Joe]

Maybe so, but 1000 ppm of H2S and you are done, unless removed and resuscitated within a couple of minutes. Lower concentrations cause unconciousness, burning of the mucosa and eyes, and the smell can be nauseating, even though the olfactory nerves are shut down in short order. Because it is soluable in oil or water, a saturated solution could be squirted/sprayed on the attacker and would result in (at the least) a readily identifiable suspect (odor), and at most a dead one (especially if he fled to an enclosed area as the gas was coming out of solution).

It also has a broad flammable/explosive range.

If the objective were removal of a threat, it could be effective.

While this is not a reccomendation, it is interesting to consider.

(Yep, 30 years in the patch.)