The problem is not new, as glasses always fog up when warm air meets cold: in other words, when you do sports and sweat, drink or prepare something warm, empty the dishwasher or get on the tram in winter. It usually only takes a few minutes for the water condensed on the lenses to disappear and your vision to be clear again. The situation is different when wearing mouth and nose protection, which is mandatory in public facilities and local transport as well as in all supermarkets due to the prevailing corona pandemic. Regardless of which respirator you wear, the lenses will always fog up. Unless you hold your breath - which of course wouldn't be a realistic solution to the problem. Instead, you could use an anti-fog spray for glasses, for example. Read here what it is and how it works.
In addition to the anti-fog spray for glasses or sunglasses, there are other tips that can help prevent your glasses from fogging up so quickly:
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