I absolutely disagree with your comment that " Not one mask will do the job for all WMD threats."

As a member of one of three federal teams that responds to chemical and biological events (we are on a deployment now) we use off the shelf equipment that is available through Lab Safety. Nothing magic just full faced powered respirators, chemical filter cartridges, and TYVEK suits, rubber gloves and boots.

Military masks are in fact effective for the range of chemical and biological agents that we are concerned about. HOWEVER, surplus masks are just that, surplus. Declared surplus due to age, defects, damage, and overuse. The filters are not fresh and in most cases are training filters, not "war" filters. Nor have they ben maintained or stored properly.

I would not risk my life with a surplus parachute or a surplus protective mask. Avoid them like the plague.

People try to make this stuff far more complicated than it really is. You just need to keep the chemical vapor away from you until it evaporates or is neutralized by the sun. I cannot envision the release of a contagious infectious organism such as smallpox, as it will spread back to the third-world paradise that it came from and kill the people that released it.

Regards