UV Light: What it is, and Why Protection is Needed

UV (Ultraviolet) radiation is a component of light that does not fall within the visible spectrum of light. Thus, even on cloudy days when there is little perceptible sunlight, your eyes can be exposed to UV rays.

There are three categories of UV radiation, which each have different levels of risk to you.

UVC

While UVC rays have the highest energy of the UV radiation varieties, and are theoretically the most dangerous for your eyes, the planet’s natural ozone layer in the atmosphere blocks almost all UVC rays and prevents them from reaching us.

UVB

UVB rays, however, are only partially filtered out by the ozone layer, with a portion making its way to us on the surface. Low doses of UVB rays are responsible for suntans, though overexposure can lead to the far less desirable sunburn, in addition to raising the risk of skin cancer. Too much UVB exposure can also lead to premature aging of the skin in the form of discolorations and wrinkles.

They can lead to eye problems as well. Too much UVB exposure can lead to photokeratitis, pinguecula , and pterygium.

UVA

UVA rays, which are lower energy than UVB and UVC, and which are closest to visible light, are particularly dangerous because they can pass through the cornea and into the retina of the eye.

Too much UVA radiation exposure can lead to the development of several types of cataracts, and may be linked to macular degeneration as well.

Levels of UV Risk

The UV index created by the National Environmental Protection Agency and the National Weather Service gives you a color-coded warning system to keep people aware of the level of UV risk on any given day.