What You Should Know About UV Rays

Stepping into the Sun’s rays on a warm summer day enlivens the spirit, as we feel the warm embrace of a star that is essential for sustaining life. Without the Sun’s gravitational pull our solar system wouldn’t exist and there would certainly be no life on Earth.

Spending time outside is crucial to our happiness and existence, and who doesn’t like a nice summer tan? However, it is important to be cautious as the Sun is a powerful star. The rays emanating from the Sun can harm our fragile human bodies if we aren’t careful. Our skin does the best it can to protect us from outside harm, including the Sun’s rays. By assisting our skin in these efforts, we can prevent skin cancer and other harmful diseases caused by excessive UV radiation.

The Sun’s UV rays travel all the way to our planet and with Earth being the third planet closest to the Sun, we feel the rays strongly. There are 3 types of UV rays, UVA, UVB, and UVC. UVC rays are the most dangerous UV rays, but luckily our atmosphere absorbs them before they can reach us. UVA and UVB penetrate the atmosphere and “play an important role in premature aging, eye damage (cataracts), skin cancers, and suppress the immune system,” according to the Skin Cancer Foundation. So what is the difference between UVA and UVB?

UVA RAYS

UVA rays are so strong they can penetrate glass! UVA rays penetrate our skin layers deeper than UVB rays can. When damage is done to the dermis from UVA radiation, premature wrinkling and skin aging occurs. Unfortunately, UVA rays are the dominant tanning ray. A tan occurs on the skin due to injury to the skin’s DNA. The skin darkens as it attempts to prevent further damage. Tanning booths use UVA rays 12 times stronger than that of the Sun to create this damage in a short amount of time.

UVB RAYS

UVB rays penetrate the epidermis, the top layer of the skin. These rays are the primary cause of skin reddening and sunburn. NASA reports that 95% of UVB rays are absorbed by the ozone in Earth’s atmosphere. UVB ray intensity varies depending on the season, location, and time of day.

UV INDEX

The World Health Organization, the United Nations Environment Programme, and the World Meteorological Organization created a UV Index to raise awareness of risks of excessive exposure to UV radiation. This Index rates locations on Earth on a scale of 0-15, 15 being the highest risk for UV exposure, and 0 being the least. Look up your area’s UV ray rating through the National Weather Service. With this knowledge, you can better prepare yourself for how much protection you need to stay safe.

Sources:

NASA

Skin Cancer Foundation

World Health Organization