Why Does Spit Keep a Scuba Mask From Fogging?

Before diving, a diver applies spit or commercial defog solution to the inside of his mask to keep it from fogging. But why does it work? A client asked me this once, and my answer was, "I have no idea, good question!" I imagine a majority of divers do not know the answer either. How mask defogging works

_{Scuba Masks}

• 6 Things to Know About Scuba Masks
• Illustrated Guide to Mask Styles and Features
• Using Corrective Lenses with Scuba Masks

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