Effective dose of miners due to natural radioactivity in a manganese mine in Hungary

In this study, short-term radon (RnDP) and thoron (TnDP) progeny measurements and dose estimation were carried out in winter and summer in a manganese mine (Hungary). Gamma-ray dose rate originating from external sources and 222Rn and 226Ra contents of spring-water from a mine was also measured. During working hours RnDP and TnDP concentration values changed between 12.1-175 and 0.14-0.42 Bq m-3, respectively. The 222Rn and 226Ra concentration values in the karst spring-water were ∼6 Bq dm-3 and 16 mBq dm-3, respectively. The radiation dose resulting from the consumption of karst spring-water was negligible. The doses from the inhalation of TnDP and external gamma radiation were of the same magnitude, ∼0.1 mSv y-1, which was rather negligible related to the estimated radiation dose of 5 mSv y-1 from RnDP. (authors)