Neutron dose estimation by 24Na measurements in the triage of exposed individuals after criticality accidents: a case study of the Tokaimura criticality accident.
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引用次数: 0
Abstract
We investigated the neutron dose estimation for the triage of personnel involved in criticality accidents by conducting 24Na measurements via the whole-body measurement method. For a case study, we examined the September 1999 Japan Nuclear Fuel Conversion Co. criticality accident (internationally known as "the Tokaimura accident"). We investigated the neutron-induced radionuclides produced in worker C's body due to the irradiation of the primary pulse. A total of 87 radionuclides were identified, with activities ranging from 1.3 × 10-19 Bq to 6.9 × 106 Bq for worker C by Monte Carlo simulations. The radionuclide with the highest activity was revealed by calculation results: 28Al (t1/2 = 2.2 min) 6.9 × 106 Bq. The specific activity of 38Cl reached a level that was three times that of 24Na. These radionuclides would severely affect the 24Na measurement in the whole-body measurements performed in the immediate post-accident period. Spectrometry would be preferable for determining 24Na specific activities by whole-body measurements at accident sites.
期刊介绍:
Radiation Protection Dosimetry covers all aspects of personal and environmental dosimetry and monitoring, for both ionising and non-ionising radiations. This includes biological aspects, physical concepts, biophysical dosimetry, external and internal personal dosimetry and monitoring, environmental and workplace monitoring, accident dosimetry, and dosimetry related to the protection of patients. Particular emphasis is placed on papers covering the fundamentals of dosimetry; units, radiation quantities and conversion factors. Papers covering archaeological dating are included only if the fundamental measurement method or technique, such as thermoluminescence, has direct application to personal dosimetry measurements. Papers covering the dosimetric aspects of radon or other naturally occurring radioactive materials and low level radiation are included. Animal experiments and ecological sample measurements are not included unless there is a significant relevant content reason.