The technique using two detectors for assay of radioactive waste drums
was given by Cesana et al. (1993). In this paper a modification to th
is method is proposed. In comparison with the former it has some advan
tages as: the statistical and maximum systematic errors are smaller, a
ctivity in a drum can be estimated quickly, and its use is more conven
ient in practice. (C) 1997 Elsevier Science Ltd.