Glasses protect the eyes from bright light and ultraviolet rays, as well as mechanical injuries. It is never unnecessary year-round weather, and the protection of eyes is a necessity, especially during high-mountain hiking and hiking. As the height increases, the intensity of UV rays increases as well if we add 80% of the light reflecting here, we will have a retina burn and risk of getting so-called “snow blindness.”
So: Ultraviolet is an invisible light for the human eye that radiates from the sun, it has a shorter wave than the purple – 180-380 nm. In small doses, it causes sunburn and, in most cases, it damages the cells, causing primary damage to the light-sensitive eye circles. There are three types of ultraviolet light: UVA 315-380 nm wavelength, UVB 280-315 nm and UVC180-280 nm most dangerous for living organisms.
Currently, UV-380 and UV-400 glasses are most common, with the first to provide adequate protection, and the second one with a backup. This type of development can be trusted only by well-known certified manufacturers. The biggest mistake you can afford is to get flaws, tinted glasses with suspicious protection from ultraviolet rays. In this case, more UV radiation than the bluff than if you did not wear glasses at all.
The sun glasses are classified in categories 0-4.
Eyeglasses 1-2 class are not glamorized glasses, including yellow and orange lenses. Suitable for gloomy weather. The unchanged requirement is the protection from ultraviolet rays.
Glasses with 3rd degree protection 92-88% prevent light and are considered the optimal option.
Glasses with 4th grade protection allow 3-7% light penetration, they use pilots, boilers, metalworkers and, of course, those engaged in high-mountaineering. It’s for people who have sensitive eyes and spend a lot of time in the sun.
It is desirable to have a few glasses or changing lenses.
Go to the mountains and protect your eyes.