NRC Approach to PWR Sump Performance Resolution

Abstract

NRC regulations in the US Code of Federal Regulations require that the emergency core cooling systems in a nuclear power plant must provide the capability for long-term cooling of the reactor core. As set forth in 10 CFR 50.46(b)(5), the emergency core cooling systems must have the capability to remove decay heat so that the core temperature is maintained at an acceptably low value for the extended period of time required by the long-lived radioactivity remaining in the core. For US plants that are licensed to the General Design Criteria in Appendix A to 10 CFR Part 50, General Design Criterion 35 specifies additional emergency core cooling system requirements, such as fuel and clad damage that could interfere with continued effective core cooling. Similarly, for plants licensed to the General Design Criteria, General Design Criterion 38 provides requirements for containment heat removal systems, and General Design Criterion 41 provides requirements for containment atmosphere cleanup. Many licensees credit a containment ...