Abstract
The aim of the present study is the development of the reliable calibration method for lung counting systems. In this study, a lung set that was constructed using a lung equivalent material was developed to simulate various source distributions within the lung. Counting efficiencies of a lung counting system were also evaluated for heterogeneous distributions of Pu and 241Am within the lung. The size of the developed lung set is similar to that of the lung for the JAERI phantom, the IAEA Asian torso phantom. The mass density of the lung set is 240kgm-3. It was found that counting efficiencies of the lung counting system for Pu/241Am loaded lung's apex are one tenth/three tenth of those for the homogenous distributions within the lung.
