I have COPD so I always use a mask when I mow the lawn..
I needed to get the mowing so I could go fishing but I was out of mask.. No problem, I found a used one in the barn that look to be in good shape.. So, I used it.. BAD mistake..! Lung infection... It took over two weeks to get the gunk out of my lungs...
Boys and girls, NEVER reuse an old face mask..!
Mold infection?
Ay..!! I would have tried cleaning/rinsing it first.
Just the dust laying around would be a mess