Recommended Strengths for Sunscreen

Sunscreen is essential for people who will be exposed to the sun's rays because it protects the skin from

damage, according to the American Academy of Dermatology, the Nemours Foundation for KidsHealth and the Skin Cancer Foundation. Sunscreens are given numbers that correspond with the amount of sun energy it would take to burn skin once the sunscreen has been applied. It would take 15 times longer to get a sunburn than normal while wearing SPF 15 sunscreen, for example.

SPF 15

SPF 15 is the minimum strength recommended by the Skin Cancer Foundation. According to that group, SPF 15 is enough protection for adults with normal skin complexions. Experts at the Skin Cancer Foundation say that sunscreens containing SPF 15 block 93 percent of the sun's UVB rays. There is currently no way to measure how much of the sun's UVA rays are blocked by sunscreen, according to the American Academy of Dermatology. However, SPF 15 sunscreen may not be adequate during extreme conditions, such as the hottest parts of the day or in regions near the equator.

SPF 30

Sunscreen lotions, creams and sprays containing SPF 30 block 97 percent of the sun's UVB rays, according to the American Academy of Dermatology. SPF 30 is a better choice than SPF 15 for people with fair complexions, skin diseases or skin conditions.

SPF 50

Sunscreens containing SPF 50 offer only 1 percent more protection from the skin's UVB rays than SPF 30 sunscreens, according to the American Academy of Dermatology. SPF 50 sunscreens mean the skin is protected from 98 percent of these rays. These sunscreens might be best for use on the face or for people with skin diseases.