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Protecting your skin.
Use a sunscreen with an SPF of least 15 daily.
Wear protective clothing.
Stay out of the sun during the midday hours (10:00 a.m. to 3:00 p.m.).
Use a higher SPF when at higher elevations.
Set a good example for your children by always using sunscreen and wearing protective clothing.
Avoiding sunbathing and tanning salons. UV rays from artificial sources such as tanning beds and sunlamps are just as dangerous as those from the sun.4
Checking your skin regularly (skin self-exam), and having your health professional check your skin during any other health exams, or at least once a year.
Ultraviolet light rays (UVA and UVB)
The sunlight that reaches the earth has ultraviolet A and B (UVA and UVB) rays. These ultraviolet lights are the main causes of damage to the skin from the sun. UVA and UVB rays affect the skin's sensitivity to sun exposure in different ways.
UVA:
Can pass through window glass.
Is not affected by a change in altitude or weather.
Is present all day and every day of the year.
Penetrates deep into skin layers.
Is 5% of the sun's rays.
Is 20 times more abundant than UVB rays.
Affects long-term skin damage.
UVB:
Cannot pass through window glass.
Causes sunburn.
Causes tanning.
Helps the body with normal vitamin D production.
Varies with the season. It is more intense in the summer than in the winter.
Varies with weather conditions.
Is more intense at midday than in the morning or late afternoon.
Is more intense at high altitudes and near the equator.
Is 0.5% of the sun's rays.
Is protected against by the sun protection factor (SPF) in sunscreens.
Is related to over 90% of nonmelanoma skin cancer.
Is related to cataracts.
Sunscreens that say "broad-spectrum" can protect the skin from both UVA and UVB rays. Sunscreens come in lotions, gels, creams, and ointments
For more info just do a search on WebMD for keywords such as: tan, tanning, sunburn, etc