When and why do glasses fog up? Surely at school you studied such a thing as condensation. So, its culprits are high air humidity and a sharp temperature drop, when glass gets from a warm and humid room into frost and vice versa. Glasses fog up: what to do? You have several options for dealing with weather conditions. Option number 1 "Chemical". You can purchase a special product that removes fogging on glass, absorbs moisture and repels it. Such a product must be applied evenly on the inner surface of the glass - it will collect all the moisture in the form of drops, which then flow down. The only drawback of this option is the quick wear of the lenses. Option number 2 "Simple". Excellent protection against moisture - antifog for glasses in the form of wet wipes or spray. How to treat your glasses from fogging is up to you. A few more tips: -If your eyesight allows you to walk on the street without glasses, then it is better to put your eyepieces in a bag, in a special case. -Before putting on your glasses in a warm bus, office or store, we advise you to wipe them with a regular or special cloth. This will remove moisture and warm the glass to room temperature.