Advances in Modeling Radiation Dispersal Device and Nuclear Detonation Effects

ABSTRACT Computer models that predict the effects of Radiation Dispersal Devices (RDD) and nuclear detonations are important tools for helping prepare for, and respond to, these threats. This paper describes recent advances made by Lawrence Livermore National Laboratory (LLNL) and collaborating laboratories in order to more realistically simulate (1) downwind deposition and dose from an RDD, (2) nuclear fallout fractionation processes, and (3) indoor radiation dose and sheltering strategies for nuclear fallout. These modeling capabilities are intended to produce nearreal-time predictions to aid emergency preparedness and response by informing protective action decisions on sheltering, evacuation, relocation, and worker protection. These capabilities are developed for use in the Department of Energy (DOE) National Atmospheric Release Advisory Center (NARAC) at the LLNL, which also serves as the operations hub for the Department of Homeland Security led Interagency Modeling and Atmospheric Assessment Center (IMAAC)