UV-C defines the ultraviolet radiation within the wavelength range of 200-280 nanometers. While the UV-A (400-315 nm) and UV-B (315-280 nm) exposure from the sun or sunbeds have some associated dangers, UV-C, also produced by the sun is the shortest of the ultraviolet wavelengths and is almost entirely filtered out by the atmosphere before reaching the surface of the earth. However, while people have little or no natural exposure to it, it has been artificially produced and successfully utilized as a bactericide and germicide for decades. It can kill or inhibit the growth of microorganisms such as viruses, bacteria, fungi, and other pathogens, providing a chemical-free alternative to other disinfection methods like the use of chlorine.

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