Indoor Tanning in Norway - Statens strålevern

Appendix B – Measurement methods
Approvals
All approvals are based on type testing according to the European Standard, EN 60335-2-27 part 2:
”Particular requirements for appliances for skin exposure to ultraviolet and infrared radiation”. NRPA
has performed such tests since 1995.
The measurements at NRPA were performed with a temperature stabilized spectral radiometer of type
Macam SR9910 from Macam Photometrics LTD equipped with a double grating monochromator. The
front optics was an optical light guide with a 15 mm diameter cosine adapted teflon diffusor. The
bandwidth was 1.3 nm (FWHM), and wavelength increment 0.5 nm. The instrument was calibrated
with traceability to NIST (National Institute of Standards and Technology) via SP Swedish National
Testing and Research Institute. The wavelength and irradiance calibration of the instrument was
checked with a mercury lamp and a 1000W QTH-lamp, before and after the measurements. The
measurement uncertainty was within ±6 %. The measurements were performed at 24°C and with the
appliance supplied at rated voltage (in Norway: 230 VAC ± 10 %), as stated in the European Standard.
All fluorescent tubes have been seasoned for 50 hours (up to 1997) or 5 hours and facial lamps for 1
hour prior to the measurements according to the European Standard. The homogeneity and maximum
UV-irradiance in the sunbeds was found using a filter-radiometer radiometer (Solar Light Co PMA
2100, UVB sensor head PMA 2101). Since 1997, the approvals were based on the maximum UV
irradiance measured anywhere in the tanning device according to the European Standard. Up to 1997,
the mean irradiance was usually recorded, i.e. the mean irradiance measured over the surface of the
device or at a distance stated in the instructions for use.
Sunbed inspections: some sunbeds are easy to find and inspect, whereas others need closer inspection.
Inspection surveys
Irradiance measurements were performed according to the European Standard in a representative
selection of tanning devices in both inspection surveys. Two different radiometers were used; a large
double monochromator scanning spectroradiometer from Macam Photometrics LTD fitted with a
quartz optical light guide (one sigma level 6 %), and a broadband radiometer (Solar Light Co PMA
2100, sensor head PMA 2101 for the UVB and PMA 2110 for the UVA). The spectroradiometer was
irradiance-calibrated against 1000-watt quartz tungsten halogen lamps, traceable to NIST (National
Institute of Standards and Technology) via SP Technical Research Institute of Sweden. The
wavelength scale was calibrated to match known emission lines from a low pressure mercury lamp. As
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