A comparative study of long-term measurements of natural gamma absorbed dose rate in outdoor air by TLD and GM detectors

Abstract

This paper investigates and compares two widely employed techniques for measuring natural gamma absorbed dose rate in outdoor air: the thermoluminescent dosimeter (TLD) and the Geiger-Mueller (GM) detector-based environmental radiation monitor (ERM). Over two decades (2003–2023), measurements were conducted at eighteen investigation sites having a wide variation of local dose rate values. The TLDs accumulated quarterly doses, while the ERMs recorded hourly dose rates. The comparison of mean dose rates obtained by the two methods agreed within ± 30% for all sites. A strong positive correlation was obtained between the two methods.