Seasonal variation of facial UV exposures in the shade

Abstract

The personal distribution of solar erythemal UV exposures to the face, head and neck was investigated for a public shade structure in the seasons of winter and summer. Calculated personal erythemal UV exposures in the shade during winter ranged from 0.3 SED per day for the top of the head to 1.8 SED per day for the chin. In comparison, erythemal UV exposures in the shade during summer ranged from 0.3 SED per day for the top of the head to 4.6 SED per day for the chin. Broadband global and diffuse erythemal UV was also measured on a horizontal plane in the open at five minute intervals during the winter and summer period. Cumulative daily global and diffuse erythemal UV exposures for winter were 22±3.8 SED and 14±3.0 SED, respectively. While, cumulative daily exposures for summer were 55±13.6 SED and 42±3.1 SED for global and diffuse erythemal UV respectively. From this research it can be concluded that anyone seeking shade under this common public shade structure for an extended period of time requires additional protection measures against damaging UV radiation.