Dosimetric investigation of the solar erythemal UV radiation protection provided by beards and moustaches

摘要

A dosimetric technique has been employed to establish the amount of erythemal UV radiation protection provided by facial hair considering the influence of solar zenith angle (SZA) and beard/moustache length. The facial hair reduced the exposure ratios to approximately one third of those to the sites with no hair. The variation of the exposure ratios over the different sites was reduced compared to the case with no beard. The ultraviolet protection factor (UPF) provided by the facial hair ranged from 2 to 21. The UPF decreases with increasing SZA. The minimum UPF was for the 53-62o range. The longer hair provides a higher UPF at the smaller SZA, but the difference between the protection provided by the longer hair compared to the shorter hair reduces with increasing SZA. Protection from UV radiation is provided by the facial hair, however it is not very high, particularly at the higher SZA.