Article

Monte Carlo simulation of lung counting efficiency using a whole-body counter at a nuclear power plant

¹ School of Physics and Information Technology, Shaanxi Normal University, Xi’an 710119, P.R. China
² School of Science, Xi’an Shiyou University, No.18, the Second Dianzi Road, Xi’an 710065, P.R. China
³ Xi’an Jiaotong University, No.28, Xianning Road west, Xi’an 710049, P.R. China
⁴ The Third Qinshan Nuclear Power Co. Ltd., Haiyan 314300, P.R. China

^* dongming-li@126.com

Received: 21 April 2015
Accepted: 27 November 2015

Abstract

In order to routinely evaluate workers’ internal exposure due to intake of radionuclides, a whole-body counter (WBC) at the Third Qinshan Nuclear Power Co. Ltd. (TQNPC) is used. Counting would typically occur immediately after a confirmed or suspected inhalation exposure. The counting geometry would differ as a result of the height of the individual being counted, which would result in over- or underestimated intake(s). In this study, Monte Carlo simulation was applied to evaluate the counting efficiency when performing a lung count using the WBC at the TQNPC. In order to validate the simulated efficiencies for lung counting, the WBC was benchmarked for various lung positions using a ¹³⁷Cs source. The results show that the simulated efficiencies are fairly consistent with the measured ones for ¹³⁷Cs, with a relative error of 0.289%. For a lung organ simulation, the discrepancy between the calibration phantom and the Chinese reference adult person (170 cm) was within 6% for peak energies ranging from 59.5 keV to 2000 keV. The relative errors vary from 4.63% to 8.41% depending on the person’s height and photon energy. Therefore, the simulation technique is effective and practical for lung counting, which is difficult to calibrate using a physical phantom.