UVC radiation has the shortest wavelength and is almost completely absorbed by the ozone layer. As such, it doesn’t really affect the skin. However, UVC radiation can be found from such artificial sources as mercury arc lamps and germicidal lamps.
UVB radiation affects the outermost layer of skin (epidermis) and is the primary cause of sunburns. It is most intense between the hours of 10 a.m and 2 p.m. when the sunlight is at its brightest. It is also more intense during the summer months, accounting for around 70 percent of a person’s yearly UVB exposure. Because of is wavelength, UVB does not penetrate glass easily.
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