In the event of a radiological emergency, early and reliable knowledge of radioactivity concentrations is important information for
organising countermeasures to protect the general public and emergency workers. This is ensured by all European countries in
operating airborne radioactivity and dose rate early warning networks. To increase the provided information, the development of new
secondary standards based on scintillation detectors for the measurement of ambient dose rate equivalent was initiated in 2014. This
paper shows the state-of-the-art of uncertainties and characteristic limits of low dose rate measurement that can be achieved by
scintillation-based detector (CeBr3) and gas-based detectors (a high-pressure ionisation chamber, HPIC). The comparison of the
devices shows the performance and the metrological potential of the CeBr3 detector: Its uncertainty is already very close to the
uncertainty of reference values. Looking at the question how to select a reference instrument, the CeBr3 detector with a special data
evaluation is even superior to the HPIC and qualifies therefore as a modern secondary standard: Providing both, dose rate and nuclide
information.
Röttger, A. & Kessler, P. (2019). Uncertainties and characteristic limits of counting and spectrometric dosimetry systems. Journal of Environmental Radioactivity, 205-206, 48–54. https://doi.org/10.1016/j.jenvrad.2019.04.012
