------ UV400 Protection
Sunglasses offer protection against excessive exposure to light, including its visible and invisible components. The most widespread protection is against ultraviolet radiation, which can cause short- term and long-term ocular problems and various forms of eye cancer. Medical experts advise the public on the importance of wearing sunglasses to protect the eyes from UV for adequate protection, experts recommend sunglasses that reflect or filter out 99% or more of UVA and UVB light, with wavelengths up to 400 NM. Sunglasses that meet this requirement are often labeled as "UV400"
● Not all sunglasses block 100 percent of UV rays. If you're unsure about the level of UV protection your sunglasses provide, take them to your eye doctor or optician for an evaluation. Many eye care professionals have instruments such as spectrophotometers that can measure the amount of visible light and UV radiation your lenses block. Almost all sunglasses block a portion of HEV rays, but some tints block more blue light than others. Blue-blocking sunglass lenses usually are bronze, copper or reddish-brown in color.
●Remember to wear sunglasses even when you're in the shade. Although shade reduces your UV and HEV exposure to some degree, your eyes still will be exposed to UV rays reflected from buildings, roadways and other surfaces.
●Sunglasses are important especially in winter, because fresh snow can reflect 80 percent of UV rays, nearly doubling your overall exposure to solar UV radiation. If you ski or snowboard, choosing the right ski is essential for adequate UV protection on the slopes.
●Even if your contact lenses block UV rays, you still need sunglasses. UV-blocking contacts shield only the part of your eye under the lens. UV rays still can damage your conjunctiva and other tissues not covered by the lens. Wearing sunglasses protects these delicate tissues and the skin around your eyes from UV damage.