Annual average and seasonal variations of indoor radon concentrations in Piedmont (Italy) using three different detection techniques

One year survey of indoor radon concentrations was carried out in public buildings, schools and dwellings of the neighbouring small towns of Nichelino and Castagnole Piemonte, nearby Turin, Piedmont (Italy), as part of a long term assessment of local radon levels. Three kinds of detectors have been deployed for nearly 500 exposures: electrects, solid state nuclear track detectors and a continuous on-line monitor. A log-normal model was applied to estimate the fraction of dwellings with high radon concentration. The resulting effective dose-equivalent for the inhabitants of Castagnole Piemonte and Nichelino, calculated from the geometric means, is 0.7 and 0.5 mSv y - 1 , respectively.