Types of UVR

Ultraviolet radiation is split into three parts:

·     UV – A, low energy (400-320 nm).  UVA is thought to contribute to premature aging and wrinkling of the skin and has recently been implicated as a cause of skin cancer.  UVA damages the dermal structures, ie collagen and elastin, turning them from strong springy spider web networks, to thick and bumpy structures like rotted elastic, - hence aging and loss of elasticity in the skin.

·     UV – B, medium energy (320-290 nm).  UVB is more dangerous than UVA and has been implicated as a major cause of skin cancers, sunburning and cataracts. 

·     UV – C, high energy (280-200 nm).  UVC is extremely dangerous but does not reach the earth’s surface due to absorption in the atmosphere.  Most of the radiation below 290 nm is absorbed by the ozone in the upper atmosphere.  Depletion of this layer increases the amount of UVC reaching ground level.