Natural radiation exposure in the vicinity of Spanish nuclear power stations.

Nationwide and regional surveys have been conducted to evaluate natural radiation exposure of people in the vicinity of the Spanish nuclear power stations. In these surveys, indoor radon, external gamma dose rates outdoors and indoors and radioactivity in soils were measured. Measurements of indoor radon concentrations were performed in 214 dwellings by using nuclear track-etched detectors. External exposure from terrestrial gamma rays outdoors and indoors were measured in a total of 596 points. Radioactivity in soil samples collected at 293 sampling sites are also reported in this paper. By taking into account all sources of natural radiation exposure, mean annual effective doses to the population in the surroundings of the six Spanish nuclear power stations have been estimated and compared with those coming from their normal operation.