Comparison of Dosimetric Methods Used in Environment

Abstract

Based on requirements felt in the domains of health physics and radiation protection, a study was made of the accuracy and sensibility of different practical methods utilized in dosimetry. The ionization chamber, the Nal true spectrum method, the method relying on the proportional counter, and soil sampling, were applied to measurements in various environments and in constant irradiation field. The three techniques first named yielded results agreeing quite well with each other in a field of constant exposure rate. The results obtained with soil sampling, using a Ge(Li) measuring system indicated that the small amount of 137Cs radionuclide remaining in the soil tended to give values somewhat higher than given by other methods. The small difference in incident radiation entering a detector between one placed in natural environment and one shielded with thin concrete could be distinguished by the Nal true spectrum method. The method utilizing the proportional counter also gave quite good results considering its small effective volume. In respect of both accuracy and sensibility, it can be concluded that the Nal true spectrum method is the best among the techniques taken up in the present study.