SCUBA diving masks often fog up as you enter water that is dramatically warmer or colder than the air temperature. A fogged SCUBA mask can impede your vision enough to make it necessary for you to abort your dive. You can prevent mask fogging with a store-bought mask defogger or you can save money by using simple household products.
You can clean your mask with a drop of toothpaste. Use the toothpaste you have around the house, as long as it is not a gel. Rub the toothpaste in circles around the mask’s lenses with your fingers, the same way you would with commercial defogger solution. Rinse the toothpaste out with clean water to ensure that no film remains on the surface of the mask’s lenses.
Johnson's Baby Shampoo
“Scuba Diving” magazine recommends using Johnson’s baby shampoo as an alternative to commercial defogger for cleaning your mask prior to a dive. This gentle solution works well on mask lenses and won’t scratch their surface. Rub a drop of the shampoo on your mask the way you would a drop of toothpaste or commercial solution, and remember to rinse your mask thoroughly to remove any film. Johnson’s Baby Shampoo is designed to be gentle on the eyes, so any shampoo you accidentally leave on your mask won’t irritate your eyes as much as a commercial defogger solution could.
If you find yourself on a dive boat with no commercial defogger, toothpaste or baby shampoo handy and no one to borrow some from, you can use your own spit to clean your mask. Many divers swear by this method, and “Scuba Diving” magazine agrees that it can work. Only use saliva as a last resort, however, because it can transfer bacteria into your mask. If you do use the saliva method, make sure to rinse your mask thoroughly before you put the mask on and again after the dive.