Assessment of Uncertainties in Early Off-Site Consequences from Nuclear Reactor Accidents

A simplified approach has been developed to calculate uncertainties in early off-site consequences from nuclear reactor accidents. The consequence model (SMART) is based on a solution procedure that uses simplified meteorology and involves direct analytic integration of air concentration equations over time and position. This is different from the discretization approach currently used in the CRAC2 and MACCS codes. The SMART code is fast running, thereby providing a valuable tool for sensitivity and uncertainty studies. The code was benchmarked against both MACCS version 1.4 and CRAC2. Results of benchmarking and detailed sensitivity and uncertainty analyses using SMART are presented.