Tanning Bed Use
The goal of a tanning bed is to replicate the effects of the sun and its UV light waves on the user's skin. Two different types of tanning beds use this method to tan: vertical and horizontal. Vertical tanning is more affective in delivering UV lights. Because the user's body is not lying horizontally on a horizontal tanning bed, it doesn't tend to have one side blocking the amount of UV exposure. Folds in the skin from lying on the clear bed floor surface could cause imperfection in the evenness of the tanning.
Function
The beds incorporate multiple long fluorescent bulbs that contain mercury, a coating of phosphorous and inert gases. The bulbs are fueled by electricity. This electricity sparks the mercury, causing it to lose its stability. The mercury then reacts by releasing energy in the form of UV radiation. It must do this in order to stay stable in light of the presence of electricity. The phosphorous coating is there to filter out the necessary wave lengths of light that the user doesn't need to tan.
Effect on Skin
The human skin is made up of multiple layers, the dermis and epidermis. The entire tanning process takes place on the epidermis, which is the outer layer. The UV light hits the skin directly and causes the melanocytes in the skin to react into producing a skin pigmenting agent known as melanin. This pigment rises through the surface and is absorbed by the skin cells surrounding it. Once this melanin comes in contact with the UV light, it darkens the color of the skin. However, this process doesn't happen immediately. Melanin production usually takes time and multiple periods of UV exposure in order to noticeably darken the skin.
