Some helpful hints for protecting yourself from sun's harmful rays

The U.S. Centers for Disease Control and Prevention offers these suggestions in ways to keep ultraviolet rays from damaging your skin:

Protection from sun exposure is important all year round, not just during the summer or at the beach. Any time the sun's ultraviolet (UV) rays are able to reach the earth, you need to protect yourself from excessive sun exposure. UV rays can cause skin damage during any season or temperature.

Relatively speaking, the hours between 10 a.m. and 4 p.m. during daylight savings time (9 a.m. - 3 p.m. during standard time) are the most hazardous for UV exposure in the continental United States . UV radiation is the greatest during the late spring and early summer in North America .

Remember: UV rays reach you on cloudy and hazy days, as well as bright and sunny days. UV rays will also reflect off any surface like water, cement, sand, and snow.

Q: What exactly are "ultraviolet rays"?

A: Ultraviolet (UV) rays are a part of sunlight that is an invisible form of radiation. UV rays can penetrate and change the structure of skin cells.

There are three types of UV rays: ultraviolet A (UVA), ultraviolet B (UVB), and ultraviolet C (UVC). UVA is the most abundant source of solar radiation at the earth's surface and penetrates beyond the top layer of human skin. Scientists believe that UVA radiation can cause damage to connective tissue and increase a person's risk for developing skin cancer.

UVB rays are less abundant at the earth's surface than UVA because a significant portion of UVB rays is absorbed by the ozone layer. UVB rays penetrate less deeply into the skin than do UVA rays, but also can be damaging.

UVC radiation is extremely hazardous to skin, but it is completely absorbed by the stratospheric ozone layer and does not reach the surface of the earth.

Q: How can I protect myself from the sun's UV rays?

A: When possible, avoid outdoor activities during midday, when the sun's rays are strongest. This usually means the hours between 10 a.m. and 4 p.m. You can also wear protective clothing, such as a wide-brimmed hat, long-sleeved shirt, and long pants.

For eye protection, wear wraparound sunglasses that provide 100 percent UV ray protection. And always wear a broad-spectrum (protection against both UVA and UVB rays) sunscreen and lip screen with at least SPF (sun protection factor) of 15. Remember to reapply as indicated by the manufacturer's directions.

Also, check the sunscreen's expiration date. Sunscreen without an expiration date has a shelf life of no more than three years. Exposure to extreme temperatures can shorten the expiration date or shelf life of sunscreen.

Q: What can excessive exposure to UV rays do to my health?

A: UV exposure appears to be the most important environmental factor in the development of skin cancer and a primary factor in the development of lip cancer.

Although getting some sun exposure can yield a few positive benefits, excessive and unprotected exposure to the sun can result in premature aging and undesirable changes in skin texture. Such exposure has been associated with various types of skin cancer, including melanoma, one of the most serious and deadly forms.

UV rays also have been found to be associated with various eye conditions, such as cataracts.