Radon exposure levels of the staff in the drinking water supply facilities in Bavaria, Germany

摘要

Within the framework of a study covering the whole of Bavaria, water supply facilities were investigated as to radon concentrations in groundwater and indoor air and as to the radon exposure levels to which the staff working in these buildings were subjected. An inquiry sheet was sent to all drinking water supply facilities in Bavaria (Germany). Two thousand six hundred facilities were asked to provide detailed information about their facility and the duration of stay and about typical work processes. Over 500 water supply facilities were selected to take a 1 -1 ground water sample and to expose track-etch detectors in order to get the mean room concentration of the main working places. Tn addition, for a period of 2 months, the personnel had to wear a track-etch detector whilst they were in the supply facilities in order to get an estimate of their individual exposure level. In the east Bavarian crystalline region, indoor radon gas concentrations of up to 300 kBq/m~3 were observed. About 10% of the processing plant workers of this region get an annual effective dose of more than 20 mSv. The application of effective means to reduce the radon exposure levels of these persons is in progress.