Mask fog is one of the more annoying aspects of diving, especially if you have a bad case that just won’t go away no matter how many times you scrub it with your own saliva at the surface. While you can certainly purchase products rather inexpensively that are designed specifically to tackle this issue, there are actually products right in your own home that can eliminate mask fog just as well or better.
Toothpaste
You read that correctly: toothpaste, the good old fashioned cleanser you use on your teeth every day. The chemicals in the toothpaste lay a protective layer across the lens of the mask thus preventing mask fog from building up inside. Try to use the simplest toothpaste possible because highly abrasive toothpaste can sometimes scratch the lens. Rub the toothpaste across the inside of the lens with a finger or soft cloth until the lens is clear.
Lighter or Matches
When a mask leaves the factory, the lens will typically have a layer of residual chemicals from the production process that will ultimately cause fogging. In order to eliminate mask fog with this trick, carefully move the flame of a lighter or match across the inside of the lens until it turns black. Once the lens has cooled, wipe away the soot with a soft cloth. There’s no need to rinse the mask after using this method, but in order to ensure all the factory chemicals have been incinerated, you may need to do it more than once. If soot ceases to form, it is a good indicator that you got it all.
Baby Shampoo
The availability of this product in your house may depend on whether any babies are present, but it is easily found at any grocery store. Apply a few drops of baby shampoo and rub it around the entire lens, or use watered down baby shampoo inside a spray bottle, to easily eliminate mask fog. After application, rinse briefly and take care not to touch the inside of the lens to avoid your skin’s natural oils compromising the protective layer you’ve just created. Baby shampoo is more desirable for some divers than regular shampoo or dishwashing soap as it is gentler on the eyes in case there is any remaining residue.