It’s an aggravating but common side effect of safety eyewear use. You’re involved in your task and everything is going well, when all at once you become aware of a reduction in peripheral vision. It had come on so gradually that you didn’t even notice it, but now you can’t see well at all. Before long the rest of the lens clouds up and you have no choice but to stop what you’re doing, remove the safety glasses, and wipe them down. Depending on where you are and what you’re doing, this can range from a minor annoyance all the way up to an extremely dangerous activity.
Don’t Let Your Prescription Safety Glasses Steam Up
The cause is humidity and temperature differential. The heat of your body temperature clashes with the exterior temperature of the glasses, and the longer you wear them, the more they steam up. Or maybe you move from a cold exterior to a heated interior (or vice-versa) and must deal with the resulting fog. There’s not much you can do to alter these conditions. What you can do is turn to an anti-fog coating to alleviate the effects.
An anti-fog coating uses molecular tension and cohesion dynamics to do its thing, and it works. Water molecules are near invisible in their smaller forms but coalesce into fog as they combine. An anti-fog coating prevents water droplets from merging. You’ll still see water appear on your lenses, but in a more clear form, and not as a vision-obstructing haze.
Anti-fog coatings can be obtained either as a liquid that is hand-applied to your lenses or in a permanent factory-applied version. The liquid is spread out over the lenses, buffed, and can last (depending on usage) up to a week before it needs to be reapplied. Wiping down your safety lenses, finger contact or other physical handling, and the flushing effects of condensation will all wear away at the temporary coating, causing you to have to reapply it more frequently.
A more convenient option is to go with Fog Free, a permanent chemically-bonded coating that is applied once when your lenses are cut and will not wear away. This coating can be applied to many different lens materials, such as polycarbonate, plastic, and high index lenses. It’s also compatible with photochromic lenses. If you’re in the market for new prescription safety glasses, and fog represents an occasional or constant annoyance, you’ll certainly want to consider adding the option of Fog Free to your lenses.