Here we go again...used a full face respirator and sanded for about a half an hour outside...i was sanding down some areas on the boat..it is a chemical respirator and when I opened up the cartridges etc...there was nothing in the mask or in the cartridge areas that resembled the white fiberglass...clean as a whistle...Am I okay by doing this...or is there another mask I should be using...thanks guys...just being mental again...