There are three types of UV light, A, B, and C; they are reviewed. DNA damage from UV light is a concern and the dose makes the difference. UVA is the tanning ray and is responsible for tanning the skin; it does not burn. UVB and C penetrate deeper and can be a problem if we burn. We need UVB to make vitamin D. UVC light is filtered by the ozone layer and protects us.
