Comparative study of Dutch and German emergency-management models for near border nuclear accidents

Four institutes, all of which are involved in nuclear-emergency management in the Dutch-German border region, have compared their short-range dispersion and radiological dose models using scenarios consisting of single-station meteorology and two dispersed radionuclides. After adjustment of some of the parameters, the consequence of the differences in parameters on the effective dose was quantified at several stages from source to exposure. Results for the neutral stability class agreed within a factor of four. Variations in wet deposition of radioactive material, giving rise to external radiation from the ground, can cause significant variations to the effective dose. Furthermore, the way the different emergency-management tools model the atmospheric dispersion for a stable stability class in the horizontal plane can generate large differences. Finally, the methodology of calculating cloudshine is not comparable among the models, which causes the effective dose near the source to show large deviations for high emission sources.