Gas Masks don't filter against fires. The Carbon Monoxide displaces oxygen, that is why firefighters have to use tanks.
I don't have a mask. But I did parlay a couple of used suits. At the time I was thinking they would be good to wear when hunting because the activated charcoal in them would block my scent when hunting.
I do have a filter mask for sanding or spraying paint. But I don't think that will qualify as a gas mask.
If somebody was to give me an M17 mask. I would take it. Figure it would make a neat Halloween costume.
OBAMA-WORST PRESIDENT EVER....Even SKOORB would be better.