Jul 08, 2023

Why Your Glasses Get Foggy and How to Stop It

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Humidity is just one of many factors that can cause your glasses to fog. Here's what causes fogging and how to fix it.

Eyeglasses have a straightforward task: to help you see better. When fog gets in the way, they do the exact opposite. For the more than 166 million Americans who wear prescription eyewear, foggy glasses are a common nuisance -- sometimes even a dangerous problem. Here's why it happens and what you can do to keep your glasses from fogging up.

Foggy glasses are the result of condensation, the simple chemical process that occurs when water vapor cools down enough to turn from a gas back into its liquid state. This can happen quite suddenly when there is a drastic difference between the temperature of a surface and the surrounding humid air.

If your lenses are cool and you step into a warm area, condensation will occur when the warm air touches your glasses, as Cleveland Clinic reported. So, if you've been outside on a cold winter day and walk into a heated room, your glasses might fog up immediately. The same thing can happen when you step out of the air conditioning into hot, humid summer air.

For many, the problem of glasses fogging up became especially common during the COVID-19 pandemic. Masks direct your warm, moist breath upward onto your glasses, and when those glasses are cool, you're likely to see fog.

Foggy glasses can be more than just an irritating distraction. If they occur at the wrong moment -- when you get ready to walk down a flight of stairs in an entryway, for example -- they can be a safety hazard. Thankfully, you can do a few things to defog your glasses quickly or even prevent them from fogging up in the first place.

As with any other everyday nuisance, people are quick to come up with their own solutions to their glasses fogging up. However, some of these tactics can actually make the problem worse or even damage your lenses. Avoid using any of the following remedies for preventing foggy glasses:

Foggy glasses can stop you in your tracks or put you in harm's way. If you typically use eyewear, it's important to know how to prevent foggy lenses or quickly fix the problem when it occurs. With a few anti-fog products, a good microfiber cloth and proper techniques for wearing a mask with glasses, you'll keep fog at bay and ensure you always have a clear view.

Get a fog-resistant coating on your lensesTreat your lenses with anti-fog productsUse the soap-and-water trickMake sure your glasses aren't too tight when wearing a maskSeal your mask tightly around your noseKeep a lens cloth with youToothpastePolyethylene terephthalate filmHand sanitizer