Jun - 28 - 2011

Sun protection against UV radiation

The sun emits electromagnetic radiations and 99% of this radiations reach the Earth as ultraviolet rays,heat and light. Heat and light are indispensable to life but too much UV can make irreparable damages on the skin and health.

The U.S. Department of Health and Human Services classify the UV rays and tanning beds as human carcinogen. It should come as no surprise to us that the UV are the main cause of wrinkles,age spots,premature aging skin and the risk of skin cancer.

What are UV rays

UV rays represent energy coming from the sun traveling in wavelenghts. Long wavelengths have less energy that the short oneself rays are shorter than infrared rays so they have more energy than the visible ones. This makes UV rays more harmful than infrared rays. Long period exposed skin at UV can cause cell deformaties by altering the genetic code and damage the cells. The effect of the skin are wrinkles,photo aging and, the worst, skin cancer.
There are 3 main types in the UV ray spectrum:UVA, UVB and UVC and they are classified according to the range of their waves.

UVA rays

UVA rays exert the least energy and have the longest wavelength from all the UV rays. They represent 95% of the radiations from the sun ranging from 320 to 400 nanometers. Because of their long wavelengths they enable them to penetrate the skin deeper than the UVB rays. Their effects are consistent throughout the day. They can cause skin aging,wrinkles and age spots if the exposure is unprotected.

UVB rays

UVB rays range from 290 to 320 nanometers. The ozone layer absorbs much of the UVB rays but still some find their way to Earth. The intensity of UVB rays varies according to location, season and time of the daybed rays are strongest between the hours of 10 AM and 4 PM and in mid summer. Prolonged exposure to UVB rays will cause damage to the skin’s superficial epidermal layers,skin reddening and sunburn. The ugly effect is that skin cancer may develop.

UVC rays

UVC rays are the most damaging because they are the shortest of the UV rays. Prolonged exposure to UVC rays can cause eye problems such as cataracts


The Environmental Protection Agency says that UV radiations ca cause this:

• Immune System Suppression
• Skin cancer
• Cataracts and other eye damage such as pigmentation
• Premature skin aging and other skin problems

How to protect yourself against the UV radiation:

• Whenever possible, choose shade during the midday hours when radiation is the strongest
• Wear clothing to protect exposed skin like long sleeves
• Wear a hat with a wide brim to protect the face, head, ears and neck
• Wear sunglasses that block as much as possible the UVA and UVB rays
• Always use a sunscreen with a Sun Protection Factor of 15 or higher

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