Performance evaluation of active dosimeters for area workplace and individual monitoring based on historical and aggregated calibration data

Dosimeter type-testing and verification, in addition to regular calibration, ensures the acquisition of high quality dosimetry data and optimization of radiation protection. Historical and aggregated calibration data of active dosimeters for individual and area workplace monitoring from several Standard Dosimetry Calibration Laboratories was collected and evaluated in terms of variation in response due to radiation-based influence quantities. These data can be used to support future update and harmonization of type testing standards. Dosimeter performance was examined in a wide range of dose rates, covering several orders of magnitude within the measurement ranges, and from 33.3 keV to 1.25 MeV photon energies, respectively. The results were evaluated against limits of variation defined in type testing standards IEC 61526:2024 and IEC 60846-1:2009 for active personal and active ambient dosimeters, respectively. Most commonly used dosimeters complied with the standard requirements, with some state-of-the-art models exhibiting excellent performance and small response variations within standard stated limits, even beyond the minimum rated ranges. However, some units had pronounced variation in response, up to +68 % for active personal dosimeters and +75 % for active ambient dosimeters. Additionally, devices with inappropriate energy compensation were identified, having an over-response up to +650 %. These findings confirm the importance of type testing of dosimeter models, along with verification and regular calibration of individual units. Performance indicators showcase that most dosimeters comply with the standards, while some behaved far better, allowing for possibility of proposing a category of radiation protection field instruments with lower uncertainties.