Influence of differences in model parameters observed in Europe and Japan, on the effective dose predicted by the European model for inhabited areas (ERMIN)

Hirouchi, Jun ; Charnock, T.*

ERMIN (EuRopean Model for Inhabited Areas), which was compared and validated with other models by EMRAS II program, is a code that provides a module to two European nuclear accident decision support systems and calculates doses for people in inhabited areas contaminated by radionuclides. Parameters in ERMIN are principally based on observations after the Chernobyl accident. However, these parameters may differ among countries. In order to understand the uncertainty and variability of calculated doses when applying ERMIN elsewhere, it is important to investigate the degree of influence of each parameter on doses. Therefore, in this study, the parameters in Japan obtained by our literature surveys were compared with those used in ERMIN. We calculated doses using the values and uncertainties of those parameters and investigated the differences in doses and the influence of each parameter on doses. The results showed that the retention parameters, soil migration parameters, air exchange rate, and indoor deposition rate have a significant influence on the dose assessment.