Method for Measurements of Terrestrial Ultraviolet Radiation on Inclined Surfaces in Personal Dosimetry Field Studies

Understanding personal ultraviolet radiation (UVR) exposure is essential for the evaluation of the health risks and benefits; however, personal dosimetry could be challenging in large-scale or/and long-term population studies. Alternatively, personal exposure could be simulated using three-dimensional models and lifestyle surveys together with data on a body position with respect to the sun. These models require a real-time input on local environmental UVR. The main challenge in using this method is retrieval of the diffuse irradiance as it requires an often-expensive tracking of solar position. In this study, a hypothesis that UVR measured on a vertical plane in the north direction can be used in the UK as a proxy for diffuse radiation was tested against direct measurements and compared with models based on solar tracker data in Chilton, UK, (51.57 degrees N) in June-July 2018. The statistical analysis over 17 days under all weather conditions showed that for 45 degrees and 90 degrees tilted surfaces the proposed method performed as well as the best of the models based on solar tracker data. A proposed system could offer a portable and low-cost alternative to measurements of diffuse radiation by solar tracking radiometers for spatial distribution of terrestrial erythema effective UVR in population field studies.