With most of the United States engulfed in a heat wave and
summer in full swing, overexposure to sunlight can occur easily due to outdoor
activities. Overexposure is an underlying cause for harmful effects on the
skin, eyes, and immune system, not to mention skin cancer. Four out of five
skin cases of skin cancer can be prevented experts believe, as UV damage is
mostly avoidable.
Simple precautions can assist in protecting your body from
overexposure while outdoors. Shade, clothing and hats provide the best
protection and applying sunscreen to those parts of the body that remain
exposed. Keep these simple tips in mind, especially for those with children.
- Limit your time in the midday sun
- Watch for the UV Index
- Use shade wisely
- Wear protective clothing
- Use sunscreen
Understanding SPF
Sunscreens use the measurement Sun Protection Factor (SPF)
to convey the degree to which you will be protected from sunburn and UVB rays. SPF
is a measure of how long you can stay in the sun without burning. The average
light skinned person can stay in the sun about 15 minutes with no sun
protection before they start to suffer minor sunburn. The SPF number is then
multiplied by this number to determine how long the average person can stay
outside.
- SPF 15:15 minutes x 15 = 225 minutes before burning (3.75 hours)
- SPF 30:15 minutes x 30 = 450 minutes before burning (7.5 hours)
- SPF 50:15 minutes x 50 = 750 minutes before burning (12.5 hours)
- SPF 100:15 minutes x 100 = 1500 minutes before burning (25 hours)
A lower SPF may protect you for short periods in the sun,
but a sunscreen with higher SPF also filters more UVB rays from sunlight.
Another important factor to look for in sunscreens is a broad spectrum
sunscreen which protects against both UVA and UVB rays. UVA rays penetrate more
deeply and are associated with long term aging of skin. UVB rays cause the
immediate damage we know as sunburn.
- SPF 15 blocks about 93% of UVB rays
- SPF 30 blocks about 97% of UVB rays
- SPF 50 blocks about 98% of UVB rays
- SPF 100 blocks about 99% of UVB rays