RADIOACTIVE QUANTITY MEASURING METHOD FOR RADIOACTIVE SOLIDIFIED WASTE

摘要

PROBLEM TO BE SOLVED: To measure radioactive quantity of a drum can radioactive solidified waste with accuracy even with concentration maldistribution and radioactive positional maldistribution inside the solid. ;SOLUTION: In this method, a gamma ray emitted from a drum can radioactive solidified waste 'A' placed on a rotating elevating platform 1 is detected by a germanium detector 7 with a collimator 5 for each of a plurality of virtual slices virtually divided along the vertical axis, and the measured radioactive quantity of each of the virtual slices is integrated to have total radioactive quantity. In this case, two direct radiation peak counting rates with different typical radioactive nuclear species energy are measured per virtual slice to determine a peak counting rate ratio, a damping factor of the peak counting rate per radioactive nuclear species is determined from the peak counting rate ratio, and a direct radiation counting rate measured for each of the radioactive nuclear species is corrected using the above damping factor to measure each of the radioactive nuclear species quantity for each of the virtual slice.;COPYRIGHT: (C)1997,JPO