Sunburn
Sunburn is the skin's acute and painful response to overexposure to the sun. The skin turns red, becomes tender or swollen, and can blister, then peel. The minimum exposure to ultraviolet radiation (UVR) required to produce an initial level of reddening of the skin (erythema) varies with each person and is referred to as a MED, or minimal erythemal dose. Most white skin (skin types I, II, and III) will burn from the sun in less than twenty minutes in the summer or in geographical regions close to the equator. First degree burns can occur in less than two hours, and skin will blister - reaching second - and possibly third-degree burns - within eight hours.
The following table shows the time to create sunburn based on your skin type and the UV level.
Skin Type |
What is Your Reaction to One Hour in Midday Sun at Start of Summer? |
Typical Characteristics |
Time to Redden
when UV Index
6 or 8 or 10 |
| I |
Always burn, no tan |
Pale white skin, blue/hazel eyes, blond/red hair |
28 21 17 minutes |
II |
Usually burn, minimal tan |
Fair skin, blue/green/hazel eyes, blond/red/brown hair |
33 25 20 minutes |
III |
Mild burn, moderate tan |
Average caucasian skin |
44 33 27 minutes |
IV |
No burn, good tan |
Light brown skin |
58 44 35 minutes |
V |
Never burn, tan |
Brown skin |
89 67 53 minutes |
VI |
Never burn, always tan |
Black skin |
167 125 99 minutes |
Regardless of how they are acquired, sunburns and tans are forms of phototrauma, or injury to the skin from overexposure to, and absorption of, ultraviolet radiation (UVR).
Sunburns and sun tans mean skin damage has occurred. They should always be avoided.
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