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Types of UV Rays

Ultraviolet rays, or UV rays, are a type of radiation that is invisible to the naked eye due to their wavelengths being shorter than visible light. These powerful rays are part of the electromagnetic spectrum, or light spectrum, that are emitted from sources such as the sun, tanning beds, black lights, halogen lights and sunlamps. The ultraviolet rays impose increasingly more damage upon a recipient as the wavelength decreases. UV radiation is subdivided into three wavelength ranges.

  1. UV-A Rays

    • UV-A rays are the most common UV radiation exposure you will most likely receive. UV-A rays account for up to 95 percent of the radiation that reaches the Earth's surface and are 30 to 50 times more prevalent than UV-B rays although less intense. UV-A rays penetrate the skin more deeply than UV-Bs and have been known to play a major part in skin aging and wrinkling. UV-A rays can damage skin cells called keratinocytes in the basal layer of the epidermis, which contribute and may possibly initiate the development of skin cancers. Tanning booths and sunlamps primarily emit UV-A rays.

    UV-B Rays

    • UV-B rays are the most destructive form of UV radiation due to the ability to cause photochemical damage to cellular DNA. These wavelengths are the primary cause of skin reddening and sunburn and usually damage the skin's superficial epidermal layers. UV-B rays provide vitamin D synthesis within the body, but these rays can cause harmful effects due to overexposure such as erythema, cataracts and the development of skin cancer. The majority of solar UV-B rays are blocked by the ozone in the atmosphere

    UV-C Rays

    • UV-C rays are shortwave radiation waves that pose the maximum dangers and cause the most destruction. The sun emits UV-C rays, but these rays tend to not be witnessed in nature since the majority of the wavelengths are absorbed in the ozone layer of the atmosphere. UV-C rays from the sun normally do not affect people due to the absorption. There are man-made UV sources that emit UV-C rays, such as arc welders which can be a hazard to your eyes. UV-C injury can be extremely painful but can usually clear up in a day or two.

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