Clinch-River Breeder-Reactor Plant System Reliability

The Reliability Program for the Clinch River Breeder Reactor Plant (CRBRP, a sodium-cooled fast breeder reactor) is an integral part of the overall CRBRP design philosophy of safety in depth. The purpose of this program is to assure that the likelihood of exceeding Nuclear Regulatory Commission dose guidelines at the plant site boundaries is less than 10-6 per operating reactor year. This goal is conservatively interpreted for the purpose of a design objective as the requirement not to exceed loss of coolable core geometry to the same maximum likelihood of 10-6 per reactor year. This requirement is allocated among shutdown systems, post-shutdown heat removal systems, and other systems whose failure could result in loss of coolable geometry, a potential initiating cause of dose limit violations. Assuring that the goal will be attained in the plant is based on reliability analysis, the redundancy and diversity inherent in the design, and the verification test program.