A survey to map areas with elevated indoor radon levels in Veneto

CRR, the Regional Center for Radioactivity, is monitoring Veneto, a region in the north-east of Italy, to trace a map of areas with elevated indoor radon levels. This survey is based on analysis of territorial distribution of radon concentration in dwellings. Maps of potential risk are searched in the upper part of the region based on the indication of a previous survey. Percentage of dwellings exceeding reference levels are estimated on the base of log-normal data distribution. Normalizations to ground floor or average housing type are produced. Preliminary results indicate the existence of three areas with elevated indoor values. Radon levels often seem to be well correlated with geology.