As scientists, Stacy and Dale should have known you can't wear a hazmat respirator with a beard. Dale and Geoffrey would have been required to shave before entering any hazardous area that requires the use of a respirator. Respirators of that style require special glasses frames to hold glasses secure in their mask. Stacey and Dale had to remove their glasses to don their masks. Given a need to wear a mask, you can't just pop the respirator on or off to put your glasses on or take them off.