Your goggles can fog up in two different ways, do you know them?

Ski goggles try to prevent fogging in a variety of ways.
First of all, most lenses have a dual-pane structure to reduce the thermic shock between the cold weather and your warm face, and they have an anti-fog layer on the inner side of the inner lens.

So fogging can be of two kinds:

1. Inside of the inner lens, and that is a fog that you can touch. In this scenario, the cases are two: either the anti-fog layer is ruined, or the conditions are so harsh that you got to the limit of your anti-fog.

2. But there is a second kind, though, that happens more often and that is reversible. And that is fogging in between the double-pane structure, so why does this happen?
   The double-pane structure isn’t sealed, because there needs to be a way for the lens to compensate for pressure changes, so there is a very small hole on the gasket. 
   The hole is really small and usually protected by the frame so humidity doesn’t easily get into the structure. 
   But, if you leave your goggles inside a wet pouch, or closed inside the car with all your wet gear for a long amount of time, humidity might make its way into it.
   The good news is that solving this is super easy: you can simply dismount the lens from the frame, and leave it in a warm, ventilated place for at least 24 hours. 
   If you want to avoid this kind of fogging in the first place, simply make sure to store your goggles in a dry place.

By understanding these two types of fogging and taking a few simple precautions, you can keep your goggles dry and your vision sharp on the slopes. Treat your gear well, and it will reward you with better performance all season long.