Studies on the Natural Background Radia1'ion in Italy

The exposure rate due to the gamma-ray natural background in some representative areas of the Country was studied by means, of a portable high-pressure iQuization ch."mlber. In ali limited area such study was integrated by a survey 0n the quality of ba.ckgrowlC! radiation, carried out by gamma spectrometric measurements. . The spectrometric study permitte<;l the determination of the contrilbutions to the total by the individual natural radioactive series and by cosmic rays, while the iouometric method measured the total values of the gamma exposure. The measurement areas were chosen on the basis of joint geological and demograph£cal considerations: they are, in fact, representative of tile main geological formations, prcferentiaUy chosen in the parts of the peninsula. characterized by a significant population density. The results of the measurements are therefore indicative of the ma.ximum range of gamma exposure to which the Italian population is subjected from natural causes . . This range appears to be rather wide, in close correlation with the geologic features oli the soil, the values of exposure rate ranging from a few p.R/hr on the alluvia up to 50--60 .uR/hr on the volcanic rocks. . The authors also measured the exposure rate due to gamma-ray background in a large city, as an introduction to a future investigation of the contribution to the exposure rate by the building materials of roads and houses.