Spectral characterization of three wearable electronic ultraviolet radiation dosimeters

Excessive exposure to ultraviolet (UV) radiation poses significant public health risks, including DNA damage and skin-related pathologies. This necessitates accurate studies and quantification of UV-radiation exposure. Various wearable UV dosimeters have been developed to address these needs, particularly for outdoor workers. For measuring erythemal irradiance, recommendations from the World Meteorological Organization exist but standardized methods for characterization and calibration of wearable UV dosimeters are currently limited. At Aalto University and at Physikalisch-Meteorologisches Observatorium Davos, three commercial electronic UV dosimeters were evaluated for their spectral responsivities using conventional measurement methods and traceability chains. The first device closely mimicked erythemal action in UV-A and UV-B regions. Two of the measured devices were found to have a higher relative responsivity of over 0.9 in the 300 nm to 310 nm range. Results were used to calculate correction factors for measuring erythemal radiance at varying solar zenith angles and ozone levels under cloud-free conditions. Typical correction factors ranged from 0.98 to 1.2. The results of the two laboratories were in good agreement for the most accurate device but deviated due to the properties of the two other devices. The measurements revealed challenges posed by these devices in terms of data management, measurement times, and deployment, highlighting the need for standardized characterization methods.