Daniel C. McCarthy, News Editor
New legislation in France has put a limit on the permissible amount of radiation in the ultraviolet B (UVB) range from sunlamps. Many officials charged with examining the UVB output of the approximately 12,000 lamps regulated under the legislation will be using the Sola-Hazard handheld UV spectroradiometer, which incorporates Solatell technology from 4D Controls Ltd.
Not all UV is equal
In 1995, France's Commission Internationale de l'Eclage published research indicating that radiation in the UVB region (280 to 320 nm) had more deleterious effects on the skin than that from the ultraviolet A (UVA) region (320 to 400 nm). The commission found that very small amounts of UVB radiation can cause damage to the skin and that it also may play the greater role in causing skin cancers. UVA, while also hazardous, provides all the benefits that attract people to sunlamps at a much reduced risk
New research published by the Brookhaven National Laboratory in Upton, N.Y., supports the French commission's assertion that UVB reacts more readily with skin, but it contends that UVA may be more responsible for the development of melanoma (see Biophotonics International, March/ April 1998, p. 12).
The commission's research set passage of the French legislation in motion. The French authorities selected the Solatell technology over the other commercially available radiometric instruments to test for compliance because of the difficulty in measuring the relatively low intensities of UVB emitted from a sunlamp compared with the high intensities of UVA radiation and visible light. Radiometric units are generally broadband and either are unable to differentiate between UVA and UVB, or they use filters that are not accurate enough for this application.
The Solatell technology is a newly patented optical arrangement incorporating a mirror that reflects only the UV spectrum, a diffraction grating that splits the UV into its wavelengths and a 512-pixel UV-enhanced detector array that detects the intensity of each wavelength. The device is calibrated for wavelength and intensity and thus is able to accurately measure the UVA and UVB present in a light source.
"The Sola-Hazard gives a simple pass or fail test of whether or not the UVB emitted from a lamp exceeds the French regulations," said Brenda Shrewsbury of 4D Controls. The device also displays the intensity of the lamp's UV output in textual and graphical format.