@article{oai:repo.qst.go.jp:00047180, author = {Tani, Kotaro and Shutt, Arron and Kurihara, Osamu and Kosako, Toshiso and 谷 幸太郎 and 栗原 治}, issue = {3}, journal = {Radiation Protection Dosimetry}, month = {Feb}, note = {Monitoring preparation for internal contamination with actinides (e.g., Pu, Am) is required to assess internal doses at nuclear fuel cycle-related facilities. In this paper, the authors focus on skull counting in case of single-incident inhalation of 241Am and propose an effective procedure for skull counting with an existing system, taking into account the biokinetic behavior of 241Am in the human body. The predicted response of the system to skull counting under a certain counting geometry was found to be only about ~1.0×10-5 cps Bq-1 one year after intake. However, this disadvantage could be remedied by repeated measurements of the skull during the late stage of the intake due to the predicted response reaching a plateau at about the 1000th day after exposure and exceeding that in the lung counting. Further studies are needed for the development of a new detection system with higher sensitivity to perform reliable internal dose estimations based on direct measurements.}, pages = {381--386}, title = {Skull counting in late stages after internal contamination by actinides}, volume = {163}, year = {2015} }