Understanding UV reflection in the urban environment

Abstract

[Abstract]: Outdoor workers in Australia are exposed to very high ambient levels of ultraviolet (UV) radiation. Studies have shown that up to 90% of outdoor workers experienced UV exposures in excess of the occupational UVR exposure standard. Surfaces that reflect UV have been shown to significantly affect UV exposures and vary with solar zenith angles (SZA) and orientation of the surface and surface type. This investigation shows that seasonal variation is just as important to UV exposures affected by reflected UV radiation. In fact, UV exposures received in cooler seasons appear to be affected more by reflected UV than in warmer seasons, despite higher levels of global UV. Such high ambient UV levels are proposed as the reason for the disparity between UV exposures measured in spring and autumn, due to proportions of direct and diffuse UV radiation, despite the use of a UV reflector that has a high UV reflectivity in comparison to natural surfaces (at least 20% in the UVB waveband).