A woman wears a face mask and warm winter clothes, with fog on the inside of her glasses. Share on Pinterest
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A sudden fog on your glasses means one of two things: You’ll either need to wait for the fog to clear from your lenses, or you’ll have to take off your glasses.

Either option presents an obvious problem. You can’t see properly, which could be a momentary inconvenience or a serious risk, depending on what you’re doing when your glasses fog up.

And, lately, with mask-wearing, due to the COVID-19 pandemic, your glasses are likely fogging up a lot more than they used to.

Fortunately, there are some proven methods that can help keep your glasses fog-free, even when you’re wearing a face covering. Read on to learn more about these techniques, as well as which methods to avoid.

Waiting for spectacle fog to clear isn’t always practical. If you’re driving, teaching, using tools, or treating patients, for example, you need clear vision at all times.

Ideally, any antifog method you use on your glasses should keep your lenses clear for an extended length of time, not just a few minutes. Additionally, it should be safe to use on the surface of your glasses.

Bearing this in mind, here are some tips that have shown to be both effective and eyewear-safe.

1. Use a nose clip

If your glasses are fogging while you’re wearing a mask, it may be because your mask doesn’t fit properly. You may want to look for a mask with an adjustable nose clip.

Once your mask is in place, pinch the nose clip to tighten the mask over the bridge of your nose. A snug-fitting mask will help keep puffs of warm breath from fogging your lenses.

If your masks don’t have nose clips, you can purchase self-adhesive silicone nose clips online or stitch in a homemade version of your own using:

  • pipe cleaners
  • paper clips
  • twist ties

Buy self-adhesive nose clips online.

2. Wash with soapy water

Just before you don your specs, wash them with a mild detergent or liquid soap. If you have time, air dry them. If you need to put them on right away, gently pat the surface dry with a soft, low-lint cloth.

Researchers have found that a very thin layer of soap molecules will remain on your glasses, forming a transparent coating that inhibits fog formation.

3. Spritz with antifog lens spray

A number of commercially available antifog sprays can coat your glasses with a see-through film that keeps fog from forming. Many are formulated for use on eyeglasses, personal protective equipment, swim goggles, and diving masks.

Look for a brand that won’t damage protective coatings on your eyewear. Steer clear of sprays made to defog auto headlights, These products aren’t intended for use close to your eyes and skin.

Buy an antifog spray online.

4. Tuck in your mask

The American Academy of Ophthalmology recommends two other strategies for keeping your breath from fogging glasses.

Slide your glasses a little further down your nose so more air can flow between your glasses and your mask, or wear your glasses over the top edge of your mask.

Depending on the style of your glasses, you may be able to inch your mask upward a bit and lower the bottom rim of your glasses over your mask. The weight of your glasses may keep air from escaping upward.

5. Secure your mask with skin-safe tape

If your skin isn’t too sensitive, you may find that a slender strip of skin-safe adhesive tape will keep your mask in place and seal the upper edge to prevent misting of your glasses.

Some people have had success with athletic tapes, which are meant to be used on skin. You could also try an adhesive bandage.

Use care with this method, though. Tape — even the kind designed for medical use on skin — can injure the delicate skin around your eyes and nose.

6. Try antifog wipes

If you want a quick and handy method, consider shopping for some antifog wipes. Some are prepackaged, single-use wipes, and others are coated microfiber cloths that can be re-used.

Antifogging sprays and wipes have been used successfully in medical settings during the COVID-19 pandemic.

Buy single-use wipes and coated microfiber cloths online.

Polyethylene terephthalate (PET) film

In a 2020 study, researchers tested an antifog film applied to the inside of surgical goggles. They found that the film reduced the clarity of their sight and caused large droplets to form on the inside surface, further impairing their vision.

Toothpaste

Sometimes touted as an antifog home remedy, toothpaste may keep fog from forming, but the small abrasive grains in some products, especially those with baking soda, can scratch the surface of your glasses. Those scratches could distort your field of vision long after the fog has lifted.

Vinegar

Vinegar won’t stop your glasses from fogging, and it could damage antiglare or scratch-resistant coatings on your lenses.

Saliva

Saliva isn’t hygienic, and it doesn’t contain any properties that would stop water from condensing on the surface of your eyeglasses.

Multiple studies have reported that hand sanitizer is an effective antifog agent in a hospital setting. It’s important to note that these studies were conducted on surgical goggles, not eyeglasses.

Many hand sanitizers contain a high concentration of alcohol, which isn’t recommended for eyeglasses because it can damage protective coatings on the lenses.

Fog is a form of condensation. Condensation happens when warm air hits a cooler surface. This causes misty droplets of water to form on a surface.

Condensation on your glasses can happen when you step out of the cold outdoors and into a heated room, or when you step out of an air-conditioned space into humid summer conditions.

And, as already mentioned, it can happen when your warm breath rises up from under a mask or face shield and hits the cool lenses of your glasses.

Fog might not be the only thing impairing your vision. To make sure you’re seeing clearly, follow these steps for cleaning your specs:

  • Start with clean hands. If you have traces of lotion or other products on your skin, it may smear on your lenses.
  • Rinse with warm water. If your home or office has hard, mineralized water, opt for distilled water to rinse surface dust off your glasses.
  • Clean with a microfiber cloth. After the initial rinse, wipe the lenses with a soft cloth.
  • Spritz on your cleaner. If you’re using dish soap to prevent fogging, a single drop will suffice. Cover the surface with soap, then rinse the glasses thoroughly.
  • Let them air dry. Air drying your glasses can help preserve more of the fog-reducing surfactant film. Or you can gently rub your lenses with a dry microfiber cloth or use canned air to dry them.

Whether you’re indoors or outdoors, wearing a mask or not, fog can form on the lenses of your glasses. Foggy glasses are not just an annoyance, they can keep you from seeing clearly while you’re doing important tasks.

To keep your glasses fog-free, you might:

  • adjust the fit of your mask so it’s clamped securely across your nose
  • wash your lenses with soapy water
  • spray or wipe on an antifog product
  • lower your glasses so they rest across your mask
  • use skin-safe adhesives to seal your mask

Using products that aren’t formulated for eyewear isn’t recommended. Products like toothpaste and vinegar may damage the coatings on your lenses. There are better, more effective methods that will allow you to see clearly while keeping your eyeglasses in good working order.