UV MEDs
MED (Minimum Erythemal Dose) is defined as the amount of sunlight exposure neces- sary to induce a barely perceptible redness of the skin within 24 hours after sun expo- sure. In other words, exposure to 1 MED will result in a reddening of the skin. Because different skin types burn at different rates, 1 MED for persons with very dark skin is different from 1 MED for persons with very light skin.
Both the U.S. Environmental Protection Agency (EPA) and Environment Canada have developed skin type categories correlating characteristics of skin with rates of sunburn.
TABLE
Skin Phototype | Skin Color | Tanning & Sunburn history | |
|
|
| |
1 - Never tans, | Pale or milky white; | Develops red sunburn; painful swelling, | |
always burns | alabaster | skin peels | |
2 - Sometimes tans, | Very light brown; | Usually burns, pinkish or red coloring | |
appears; can gradually develop light | |||
usually burns | sometimes freckles | ||
brown tan | |||
|
| ||
3 - Usually tans, | Light tan; brown, or | Rarely burns; shows moderately rapid | |
olive; distinctly | |||
sometimes burns | tanning response | ||
pigmented | |||
|
| ||
4 - Always tans; | Brown, dark brown, or | Rarely burns; shows very rapid tanning | |
rarely burns | black | response |
44
