Contribution of the Exposure Pathways After a Severe Accident

A radiological dose assessment calculates the amount of radiation energy absorbed by a potentially exposed individual as a result of a specific exposure. Public can be exposure from several exposure pathways. External doses occur when the body is exposed to radioactive material outside the body. When making the emergency preparedness for severe accident from NPPs, therefore, we need to have comprehension about those exposure pathways. Thus, in this study, an evaluation of external and internal dose from radioactive materials during severe accident was performed to find out exposure pathway from which the dose has the highest value for several radionuclides. The basic study to make out the relation between exposure pathways and dose from them was performed. In the emergency phase, the most affecting nuclide type on public was noble gas, especially "1"3"3Xe, and the dominant exposure pathway was could shine. Also, in the long term-phase, the most affecting nuclide type on public was fission product, especially "9"0Sr, and the dominant exposure pathway was water ingestion. The information of the dose composition from exposure pathway obtained in this study might be basic data for making emergency preparedness plan for severe accident. In the future, assessment of the source term is expected to enhance the reliability of dose assessment during severe accidentThis work was support by Nuclear R&D Programs of Ministry of Science, ICT and Future Planning of Korea (Grant No. 2012M2A8A4025914