New Scuba Diving Masks:
Used Scuba Diving Masks:
Masks should be treated with a defogging agent before every dive. If treatment with a defogging agent does not prevent the mask from fogging, it is possible that some residue is left over from the manufacturing process. Try the toothpaste or flame tricks to remove the remaining residue.
Any agent that prevents condensation from adhering to the inside of the mask's glass will keep the mask from fogging. See why defogging agents work. There are numerous options:
1. Spit: Spit on the inside of the mask and rub it around with your finger. Dunk the mask briefly in fresh water. The goal is to leave thin layer of saliva on the inside of the glass. Spitting does not work well if the mask dries out before diving, so use this technique immediately before the dive.
2. Commercial Defogging Agents: Commercial defogging agents are specifically designed to coat a mask's lens, and many divers find these products more effective than spit. Put a few drops of the defogging liquid in the mask, rub it around with a finger, and rinse briefly with fresh water. Remember, the idea is to leave a thin layer of the defogging agent inside the mask, so do not rub out the defog when rinsing the mask.
3. Baby Shampoo: Baby shampoo can be used just like commercial defogging solution. Many divers carry a bottle of watered-down baby shampoo with their dive gear. A few drops rubbed into the lens and then briefly rinsed out will keep a mask from fogging. Baby shampoo is preferable to standard shampoo, as it is generally hypo-allergenic, less irritating to eyes, and biodegradable. Baby shampoo smells good, too.
4. Glycerin Soaps and Dish Washing Detergents: Glycerin soaps and dish washing detergents can be used the same way as baby shampoo. Put a few drops on the inside of the mask, rub them in, and rinse briefly. If a mask leaks, it is possible that the water will carry whatever defogging agent is used into the diver's eyes. The one problem with these products is that they really burn the eyes. Glycerin soap and dish washing detergents sometimes are not biodegradable. Be sure to not dump any non-biodegradable defogging agents into the water.
5. Toothpaste: Rub a non-abrasive toothpaste on the inside of the mask lens until it coats the glass completely. Rinse the mask gently with fresh water until the lens is clear. If a diver is highly sensitive to minty fragrances, the air inside the mask may burn his eyes or cheeks during the dive. Before diving for the first time after using toothpaste as a defogging agent, wear the mask for a few minutes to make sure the fragrance is not irritating.
6. Potatoes: A cut potato rubbed on the inside of a mask lens has been said to keep a mask from fogging. Rub the potato on the glass, rinse briefly, and dive. This method is a bit of a diving urban legend, but feel free to test it out the next time there is a potato and a knife handy before the dive.