Prevent fogging glasses when using dust mask
Anyone who wears glasses and has tried to use a dust mask while breathing hard in cold weather know it won’t be long before you can not see. Even if you buy the nicer dust mask with two straps and the metal nose bar you still end up with a gap across the bridge of your nose. The warm moist air quickly condenses on your glasses.
I have found a way to prevent this problem. I first trim the extra material from the top of the dust mask just above the metal strip (see red line on photo). Put on the dust mast and adjust the nose strip. Then cut a small strip of one inch wide waterproof medical tape (see photo). It should be about 1.5 to 2 inches. Place the tape across the top of the dust mask below your eyes.
The waterproof tape will not come off when you sweat and it will not allow the air to come up under your glasses. I use this method a lot and it has proven very successful.