Uv (ultra violet) radiation, Uv meds – DAVIS Vantage Pro Console User Manual

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Appendix A: Weather Data

reading gives a measure of the amount of solar radiation hitting the solar
radiation sensor at any given time, expressed in Watts /sq. meter (W/m

Solar radiation requires the solar radiation sensor.

UV (Ultra Violet) Radiation

Energy from the sun reaches the earth as visible, infrared, and ultraviolet
(UV) rays. Exposure to UV rays can cause numerous health problems, such
as sunburn, skin cancer, skin aging, and cataracts, and can suppress the
immune system. The Vantage Pro can help analyze the changing levels of
UV radiation and can advise of situations where exposure is particularly
unacceptable. UV radiation requires the UV radiation sensor. The Vantage
Pro displays UV readings in two scales: MEDs and UV Index.

CAUTION:

Your station’s UV readings do not take into account UV reflected off snow, sand, or water,
which can significantly increase your exposure. Nor do your UV readings take into account
the dangers of prolonged UV exposure. The readings do not suggest that any amount of
exposure is safe or healthful. Do not use the Vantage Pro to determine the amount of UV radi-
ation to which you expose yourself. Scientific evidence suggests that UV exposure should be
avoided and that even low UV doses can be harmful.

UV MEDs

MED stands for Minimum Erythemal Dose, defined as the amount of sunlight
exposure necessary to induce a barely perceptible redness of the skin within
24 hours after sun exposure. 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. See “

” for a description of skin types.