Tanning lamp

Tanning lamps (sometimes called tanning bulbs in the United States or tanning tubes in Europe) are the part of a tanning bed, booth or other tanning device which produces ultraviolet light responsible for tanning. There are hundreds of different kinds of tanning lamps most of which can be classified in two basic groups: low pressure and high pressure. Within the industry, it is common to call high-pressure units "bulbs" and low-pressure units "lamps", although there are many exceptions and not everyone follows this example. This is likely due to the size of the unit, rather than the type. Both types require an oxygen free environment inside the lamp.

Fluorescent tanning lamps require an electrical ballast to limit the amount of current going through the lamp. While the resistance of an incandescent lamp filament inherently limits the current inside the lamp, tanning lamps do not and instead have negative resistance. They are plasma devices, like a neon sign, and will pass as much current as the external circuit will provide, even to the point of self-destruction. Thus a ballast is needed to regulate the current through them.

Tanning lamps are installed in a tanning bed, tanning booth, tanning canopy or free standing single bulb tanning unit. The quality of the tan (or how similar it is to a tan from the natural sun) depends upon the spectrum of the light that is generated from the lamps.

High-pressure bulbs are 3 to 5 inches long and typically powered by a ballast with 250 to 2,000 watts. The most common is the 400 watt variety that is used as an added face tanner in the traditional tanning bed. High-pressure lamps use quartz glass, and as such do not filter UVC. Because UVC can be deadly, a special dichroic filter glass (usually purple) is required that will filter out the UVC and UVB. The goal with high-pressure tanning bulbs is to produce a high amount of UVA only. Unfiltered light from a high-pressure lamp is rich in UVC used in germicidal lamps, for water purification, but it damages human skin.

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