Open AccessVolumetric radioassay of lead bricks being considered for unrestricted release
Author(s) -
R.J. Gehrke,
S.J. Losinski,
G.L. Seal
Publication year - 1995
Language(s) - English
Resource type - Reports
DOI - 10.2172/33115
Subject(s) - detection limit , brick , radionuclide , monte carlo method , conventional pci , environmental science , scintillation , nuclear engineering , lead (geology) , radiochemistry , detector , materials science , nuclear medicine , physics , statistics , mathematics , nuclear physics , chemistry , engineering , geology , medicine , optics , composite material , geomorphology , psychiatry , myocardial infarction
The hardware, software, and a protocol have been developed for the screening of lead bricks for free release or recycle from the Idaho National Engineering Laboratory. The procedure for measuring the background from a sampling of ``clean`` lead bricks and for deducing the decision limits (in pCi/g) have been developed. At the decision limit, a radioactive lead brick would be detected with 95% confidence if it were present. The total and peak efficiencies of a 2.54-cm diameter {times} 2.54-cm high NaI(Tl) scintillation detector for the counting geometry of the present study were measured with a mixed radionuclide standard and calculated with a Monte Carlo program, CYLTRAN. The deduced decision limit for the counting conditions of the present study were 0.0588 pCi/g by analyzing the entire spectrum and 0.256 pCi/g by analyzing the 661-keV peak region for a 900-second count