Depends on exposure: Most people with black skin will have a skin protection factor naturally of about a 3-4, depending on depth of color. An SPF 15 filters out approximately 93 percent of all incoming UVB rays. SPF 30 keeps out 97 % and SPF 50 keeps out 98% of the harmful rays, but all products take about 20-30 minutes to become effective and should be reapplied after 2-3 hours to maintain protection.
Answered 12/15/2015
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A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
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