To distinguish americium-241 in human lungs from
translocated activity in the tracheobronchial lymph
nodes (TBLN), two intrinsic germanium detectors were
collimated with 0.3-cm lead sheeting.
A tissue-
equivalent phantom containing either 620 nCi (22.9 kBq)
in the lungs or a 2200 nCi (81.4 kBq) TBLN point source
was counted; as...