As the issue of training safety, or the lack thereof, and the oft heard rebuttal of "suck it up" to training regulations, here's the full details on HC smoke....
From B-GL-385-007/PT-001 [unrelated portions removed]
Sect 5-21
The safety precautions for the various smoke pots are as follows:
a. wearing a gas mask is mandatory in the presence of hexacloroethane (HC) smoke
b. personnel must don gas masks before using smoke and remain masked until the smoke has dissipated
c. the smoke must not be directed towards military or civillian establishments or towards trenches containing personnel who are not protected or unable to don masks
d. [snip]
e. smoke must not be directed towards fibua sites casemates or vehicles in which it cannot disperse easily
f. before using hexachloroethane smoke, all personnel not involved in training will leave the area
g. personnnel who are not taking part in exercises where hexacholoroethane smoke will be present must, prior to the start of each exercise, receive a briefing on the health hazards and mandatory preventative safety precautions
From the Agency for Toxid Substances and Disease Registry http://www.atsdr.cdc.gov/tfacts97.html
How can hexachloroethane affect my health?
Mild skin irritation has been reported by workers at a munitions factory who were exposed to low levels of hexachloroethane. The workers were wearing protective clothing that greatly reduced exposure. No other information is available concerning health effects in people exposed to hexachloroethane.
Based on animal studies, hexachloroethane in air can irritate your nose and lungs and cause some buildup of mucus in your nose, much like an allergy. It can also irritate your eyes and make them tear.
If you breathe high levels of hexachloroethane vapor, your facial muscles may twitch or you may have difficulty moving. However, these effects have been seen in animals exposed to levels far greater than those found during its use or those expected in areas near a hazardous waste site.
Hexachloroethane is not a very toxic substance. If you are exposed to a large amount for a long time, your liver could be affected. There is also a slight chance that your kidneys could be damaged. Animal studies have not shown hexachloroethane to cause birth defects or to affect reproduction.
End result, occaisonal accidental exposure to HC smoke won't kill you, howver, if you're going to be using it, the rules say wear a gas mask, and it's toxic, so wear a gas mask. The Grenades and Pyrotechnics Manual lists a number of smoke pots, most of which to the best of my knowledge,
are no longer in use, and I can't find an updated copy which lists current pyro, however, as far as I know, the "lime green" smoke pots do still use HC smoke, while the "forest green" smoke "grenades" as well as the coloured marker smoke do not use HC smoke. If it was a lime green coloured smoke pot of some sort, the individuals were likely exposed to HC smoke.
