Ultraviolet Radiation

An Ultraviolet meter is used to tell people how long they can be in the sun without protection at different times throughout the day before sunburn is likely. Each day the intensity of the sun's UV rays are calculated on a scale of 1-15. The higher the number on the scale, the more intense the UV radiation is, and therefore the more rapidly sun damage to your skin begins. Five categories are used to describe the strength of UV radiation:

Minutes before skin is damaged

On most days the UV radiation reaches its peak intensity at approximately 1 p.m. At this time sun exposure should be limited.

The Food and Drug Administration (FDA) and the American Academy of Dermatology have described six skin categories, listed below.

FDA Skin Type	Skin Reaction to the Sun	Description	Skin Category
I	Always burns easily, never tans, extremely sun sensitive	Red-headed, freckles, Celtic, Scottish, Irish	Light
II	Always burns easily, tans minimally, very sun sensitive	Fair-skinned, fair-haired, blue-eyed Caucasians	Light
III	Sometimes burns, tans gradually to light brown, minimally sun sensitive	Average skin	Medium
IV	Burns minimally, always tans to moderate brown, minimally sun sensitive	Mediterranean-type Caucasians	Medium
V	Rarely burns, tans well, skin not sensitive to sun	Middle Eastern, some Hispanics and some African-Americans	Dark
VI	Never Burns, deeply pigmented, skin not sensitive to sun	African-Americans	Dark