How harmful is UV radiation?
Generally, the shorter the wave-length, the more biologically damaging UV radiation can be if it reaches the Earth in sufficient quantity. • UV-A reaches the Earth from the sun in the greatest quantities. Recent information suggests that UV-A can damage the skins immune system. UV-A from the sun passes right through the ozone layer to the Earths surface with little attenuation. • UV-B radiation is potentially very harmful. Fortunately, most of the sun’s UV-B radiation is absorbed by ozone in the stratosphere. • UV-C radiation is potentially the most damaging because it is very energetic. Fortunately, all UV-C is absorbed by oxygen and ozone in the stratosphere and never reaches the Earth’s surface.
