A pretty basic question – but one of interest to tan biz newcomers: What is a low-pressure sunlamp?
In the tanning salon business, low-pressure sunlamps are most prevalent by a large margin. They are usually five- or six-foot, linear glass tubes that utilize fluorescent technology. The term “low-pressure” (LP) refers to the pressure contained within the glass tube. This pressure amounts to somewhat less than one atmosphere; actually, a slight vacuum. When an LP lamp breaks, it collapses or implodes, as the external positive atmosphere rushes to fill the space within the lamp at negative atmosphere.
When low-pressure lamps receive the proper electrical voltage and current, an arc is created from one end of the lamp to the other. This arc vaporizes a small amount of mercury in the lamp, resulting in ultraviolet emissions. The mercury’s UV emissions excite a thin coating of phosphor (or a blend of phosphors) on the inside of the lamp wall. The phosphor used to make the sunlamp determines its output; the phosphor converts mercury output to the UV tanning spectrum common to LP sunlamps (Figure 1). Most of the UV emissions are not visible; this is the UV needed to stimulate the tanning process in our skin. A small amount of the emissions are visible; but while only a small portion of the visible light assists in the pigment darkening process (a cosmetic tan), it is a handy way to tell that the sunlamp is functioning.
The output from LP sunlamps is a combination of UVB (280-320 nanometers), UVA2 (320-340nm) and UVA1 (340-400nm), plus the small component of visible light described earlier. Differences in the effectiveness of one lamp type to another are modified through adjustment of the phosphors. UVB stimulates melanin production and can burn the skin if overexposed; UVA2 acts a lot like UVB, with melanin production and some pigment darkening; it is also closely associated with elastosis (photoaging, wrinkles). UVA1 penetrates deeper past the surface of the skin and is primarily responsible for pigment darkening. The newer low-pressure lamp models focus on providing enough UVB to stimulate the melanin and aid in production of vitamin D, plenty of UVA1 and less of UVA2.
Got questions or comments about this topic? Suggestions for future articles? Email sales@wolffsys.com or call Team Wolff at 800.959.6533.
