Glossary Of Terms: Lamps

TM. Represents time for melanogenesis in a typical sunbed.

T12. Refers to the diameter of the lamp, where T equals the diameter of the glass in 1/8-inch steps (12 X 1/8 = 1.5 inches).

Ultraviolet light (UV). Refers to light waves below 400 nm.

• UVA1—ultraviolet light waves between 340nm and 400nm; oxidizes melanin on and beneath the skin surface.
• UVA2—ultraviolet light waves between 320nm and 340nm; stimulates melanin production, some erythema and pigment darkening; closely associated with elastosis (photo-aging or wrinkles).
• UVB—ultraviolet light waves between 280nm and 320nm; stimulates melanin production; primary agent for erythema.
• UVC—ultraviolet waves between 200nm and 280nm; powerful light not used for tanning; generally for germicidal uses, etc.

UVB percent. Refers to the ratio of UVB to UVA.

VHO lamps. VHO, or “very high output,” lamps feature high power consumption—generally between 140 watts and 160 watts, but can be more than 200 watts—as well as electrodes with a cooling zone at each lamp end.

Watt (W). The measure of power consumption and heat, but not necessarily output.