Here's a hint on respirators guys. Cartridges (or masks themselves, if they don't have replaceable cartridges) that are rated to remove organic vapors ALL have limited lifespans. They don't somehow magically separate out the bad vapors and eject them indefinitely. They just use chemicals inside the cartridges that bond with the vapors as you inhale and keep them from getting to your lungs. But there is a limit to how much these cartridges can absorb. The other thing is that the cartridges don't turn off when you take the mask off. IE if you take it off and put it in a drawer in your shop for 3 months, odds are that when you take it out and put it back on, it's not going to be doing you any good beyond simply removing dust from the air you inhale. You need to read the usage guidelines that came with your mask or cartridges for the unopened expiration date, the max time of efficiency after opening, and the total hours of usage that the cartridges are rated for, and if any one of them is past, replace them. If you don't know what the cartridges you have are for, or don't know how old they are, or don't know how long since your opened them, for pete's sake, go get some new ones! All the good reasons you got a mask for in the first place are just as valid for getting a new set of cartridges if you need them. Once you have some new cartridges, rated for the specific hazard you are working with, take care of them. Seal the whole mask in a big ziplock bag when you are not wearing it, both to keep the interior clean and to keep the cartridges from filling up with chemicals out of the air while you are not using it.
A good rule of thumb is, if you are wearing a mask to keep from smelling something, and you still smell it, IT AIN"T WORKING! It's either too old, or not the right kind of cartridge in the first place.
