Model descriptions for OSCAAR version 2.0

Risk Analysis Research Group, Nuclear Safety Research Center

The Japan Atomic Energy Agency's Nuclear Safety Research Center is developing the Level 3 PRA code OSCAAR as part of its research on probabilistic risk assessment (PRA) for nuclear power plant accidents. OSCAAR is a computational code that evaluates the advection, diffusion, and deposition of radioactive materials released into the environment under various meteorological conditions, based on source terms obtained from Level 2 PRA. It can probabilistically assess the radiation doses and health effects to the public caused by these radioactive materials. OSCAAR can account for the dose reduction effects of protective measures implemented during an actual nuclear power plant accident, thereby contributing to the preplanning of countermeasures and plans to reduce the exposure of residents near nuclear power plants during an accident. This report is a manual explaining the analysis model used in OSCAAR code version 2.0.