[Hellfighter]

if i remember right for the M17A1 it was like 8hrs of use it no longer any good.

there are two types filters one for training with and a combat model, basic they only last 8hrs.

break the seal don't matter you can still use it.

i would seal it back up best you can, vacuum seal better.

the air will get to it.

by the way never use any rubber cream or baby oil for it, baby powder is best for the mask keep it dry.

normal wear is ok rain and so on, but for maints on it baby powder.

you can clean it with light soap water and let it air dry out, after use baby powder on it help to keep skin rash down beside make it easy slid on and off.

10yrs Army Vet Infantry 77-87

*no bio-mask will help you from nuclear dust (dirty bomb) clouds. the only thing will stop that is lead and a lot of pure lead walls for sample. you need a lead suit to help in that area and 2-3min get it on.