Application of the Single Failure Criterion to the Advanced CANDU Reactor (ACR)

Abstract

The Single Failure Criterion (SFC) is intended to address random failures by providing a measure of redundancy to ensure adequate reliability of important safety functions. In the traditional CANDU design practice, this is achieved by having two sets of systems that can perform the essential safety functions to satisfy a probabilistic safety goal, supplemented by implementation of redundancy in the special safety systems, comprising shutdown systems 1 and 2, the emergency core cooling system, and the containment system. To facilitate licensability in international markets, and to be consistent with international standards and practices, the accepted approach of applying the SFC within systems or groups of systems that perform the important safety functions required for the design basis events has been adopted. This paper provides an outline of how the SFC is applied to the ACR design.