PHOENIX — Ultraviolet light is a type of electromagnetic radiation. It's responsible for the glow in a black light poster, or the bronze on your skin from a summer tan.
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Overexposure to UV radiation will damage living tissue resulting in a sunburn.
Electromagnetic radiation beams down from the sun. It is transmitted in particles at different wavelengths and frequencies. This broad range of wavelengths is known as the electromagnetic (EM) spectrum.
For general purposes, this spectrum is divided into seven regions by order of decreasing wavelength and increasing energy/frequency.
The most common designations are radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV), X-rays and gamma-rays.
After exposure to UV rays, your body's natural defenses kick in. A pigment called melanin absorbs UV light and disperses it as heat.
If your body senses sun damage, it sends melanin into surrounding cells and tries to protect them from further damage.
This process results in the skin becoming darker.
If the exposure continues, UV radiation can overwhelm the body's defenses triggering a toxic reaction, or sunburn. The body recognizes this problem and rushes the area with blood to help with the healing process.
An easy way to remember this, melanin is natural sunscreen.
The UV Index is the expected intensity of ultraviolet radiation from the sun. It provides you with a guideline to know how much exposure the average person can tolerate before a toxic reaction.
However, the fine print is some people are more prone to radiation risks. Light hair, light eyes and family history may increase your likelihood of sun damage.
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