U.S. NRC Containment Integrity Programs

The US Nuclear Regulatory Commission (NRC) is sponsoring a set of programs whose objectives are to provide the data base required for the qualification of methods for predicting the response of containment buildings for light water reactors (LWR) during severe accidents (those beyond design basis events) and extreme earthquakes. This set of programs is examining the modes of containment failure that result in the release of radioactive materials beyond the containment boundary. These modes include structural failure of the containment building, leakage through or past the penetrations (electrical or mechanical), failure of containment isolation systems, or failure of the base mat by the molten reactor core. The first two modes of failure, which are being studied by Sandia, are discussed in this paper.