HID/High-Pressure Tanning

HID/High-Pressure Tanning

by Patricia E. Reykdal and Donald L. Smith

Traditional vs. New-Era HID/High-Pressure Sunlamps
The first HID/high-pressure (HP) systems available in America were “traditional” units that utilized absorption filters that removed most of the UVB wavelengths and, since they only had sunlamps in the canopy, required that the tanner flip over in the middle of the session. Many of the new-era units utilize absorption filters that allow more UVB photons to be transmitted, and most of them provide 360 degrees of coverage— which means the client tans both sides of the body at the same time. However, it is the difference in the transmission properties of the absorption filters used in the new-era systems that primarily differentiates them from traditional HID/HP systems.

Graph 1. As you can see from the graph below, the new-era HID/HP system has both a “right shift” of photons into the tanning-power region and a “left shift” of photons into the erythemal region that primarily determines the Te (4 MED) time of the unit. Thus, the new-era HID/HP system has a shorter Te time and more tanning power than does the traditional HID/HP system.

Graph 2. This graph shows why the new-era HID/HP sunlamps have much shorter Te times than do traditional HID/HP sunlamps. As you can see, the new-era HID/HP sunlamp has more photons in the 286 nm-302 nm wavelength area, and that explains why the former has a Te time of 12 minutes and the latter has a Te time of 22 minutes. (Keep in mind that the newera HID/HP unit has 360-degree coverage [i.e., sunlamps in both the bench and canopy] while the traditional HID/HP unit only has sunlamps in the canopy. Thus, the new-era HID/HP system has a MET [maximum exposure time] of 12 minutes while the traditional HID/HP system has a MET of 12 minutes per side.)

Graph 3. As you can see from the graph below, both traditional and new-era HID/HP systems have very short Tt (tanning) times when compared to traditional low-pressure sunlamps, which explains why these units are so popular with clients. Keep in mind that since the traditional HID/HP system requires that the tanner flip over halfway through the 24-minute session, the Tt time of 6.3 minutes must be doubled; thus, the Tt-Te time ratio is 1.9. The new-era HID/HP system has 360-degree coverage and it has a 2.4 Tt-Te time ratio. by Patricia E. Reykdal and Donald L. Smith Tanning HID/High-Pressure Tanning HID/High-Pressure Reader Service No. 57

Graph 4. What about stimulation of vitamin D? As you can see from the graph below, the traditional HID/HP system has a low ability to stimulate the production of vitamin D—you must tan for more than four times the MTI—while the new-era HID/HP system has a very good vitamin D-effective (vD-eff) time. In addition, as everyone knows, traditional HID/HP systems also have a limited ability to stimulate the production of the melanin required for future tanning sessions, which is why savvy salon owners recommend clients alternate between tanning in a traditional HID/HP system and a higher-UVB low-pressure system.

Graph 5. How do traditional and new-era HID/HP sunlamps compare to traditional and new-era low-pressure sunlamps? As you can see from the next graph, the new-era 160-watt sunlamp 1) has significantly more power than the 400-watt HID/HP sunlamp; 2) comes very close to spectrally matching the 620-watt HID/HP sunlamp; and 3) comes much closer to matching the 1,000-watt HID/HP sunlamp than does the traditional 160-watt sunlamp. Thus, in a hybrid tanning system whereby both HID/HP and low-pressure sunlamps are utilized, combining HID/HP sunlamps and new-era 160-watt sunlamps will provide a much better tanning environment than is possible when a traditional 160-watt sunlamp is combined with an HID/HP sunlamp.

The Bottom Line
New-era 160-watt sunlamps come much closer to spectrally matching HID/HP sunlamps, and both “new era” modalities (low-pressure and HID/HP) have significant benefits, i.e., more tanning power and vitamin-D stimulation power and much less potential to cause skin damage and immunosuppression when compared to both “traditional” modalities. That is good news for salon owners, clients and the indoor tanning industry.