Protect yourself from excessive exposure to the ultraviolet rays (UV) of the sun. Exposure to UV radiation has increased over the years due to the depletion of the ozone layer, a naturally-occurring gas that filters the sun's UV radiation. For some people, overexposure to UV rays can lead to skin cancer, cataracts and weakened immune systems. To protect against sun-related damage, follow these rules:
:: Wear sunglasses that provide 100% of UVA and UVB protection greatly reduce sun exposure that can lead to cataracts and other eye damage.
:: Use a sunscreen with UVB & UVA SPF of 50. Apply it liberally to all exposed areas of your body, particularly your ears, face, back and neck. Reapply every 2 hours when working, playing, or exercising outdoors; even waterproof sunscreen can come off when you towel off sweat or water.
:: Listen to the weather reports. The UV Index, developed by the National Weather Service and the Environmental Protection Agency, provides a forecast of the expected risk of overexposure to the sun and indicates the degree of caution that you should take when working, playing or exercising outdoors. Weather predictions in print and broadcast media announce the UV Index daily.
::  Stay clear of the midday sun as much as possible. The sun's UV rays are strongest between 10 a.m. and 4 p.m. If you're spending the day at the beach, take refuge under a beach umbrella during those hours when the sun's rays are most intense.
:: Dress Up. Wear light, long-sleeved shirts and ankle-length pants if you're going to be out in the sun for long periods of time and you'd rather not wear sunscreen. A wide brimmed hat will shade your face, neck, ears and eyes. 

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