Reusing disposable dust masks?

is it bad to reuse disposable dust masks. Is it bad to share it with someone else?Reusing disposable dust masks?
unless either of you have has any illness that can be transfered easily, either by contact or via bodily fluids, sharing shouldnt be a problem. as for re-using them, i would advise against that. it doesnt cost much to use fresh ones, and for the sake of keeping your lungs clean, i wouldnt take the chance.