In the 1990s, regulations in some countries (. Sweden, France) limited to the maxi- mum proportion of UVB in the UV output of tanning appliances. However, in practice, the UV output and spectral characteristics of tanning appliances vary considerably. Surveys in the United Kingdom on tanning appliances operated in public or commercial facilities revealed sub- stantial differences in UV output, mainly for UVB, for which up to 60-fold differences in output have been observed (Wright et al., 1996; McGinley et al., 1998). The proportion of UVB in total UV out- put varied from to 4%, and thus emission spectra similar to that of the sun in the UVB range were sometimes.
