ANS 58.9

Abstract

This standard provides criteria for the designer which interpret the requirements of Title 10, Code of Federal Regulations, Part 50, "Licensing of Production and Utilization Facilities," Appendix A. "General Design Criteria for Nuclear Power Plants," with respect to design against single failure in safety-related Light Water Reactor (LWR) fluid systems [1]², Means of treating both active and passive failures are addressed for safety-related fluid systems following various initiating events. Current acceptable practice is used as a basis for these criteria. <br>Failure criteria for the electric power systems and the protection systems are provided in IEEE Std 308-1980 "IEEE Standard Criteria for Class 1E Power Systems for Nuclear Power Generating Stations', IEEE Std 279-1971 "IEEE Standard Criteria for Protection Systems for Nuclear Power Generating Stations" (N42.7-1972), IEEE Std 379-1977 "IEEE Standard for Application of the Single-Failure Criterion to Nuclear Power Generating Station Class IE Systems", and IEEE Std 603-1980 "Standard Criteria for Safety Systems for Nuclear Power Generating Stations", [2,3,4,5] Failures of structural components, such as braces, supports, or restraints, as well as occurrences involving common mode failures, are excluded. <br>² Numbers in brackets refer to corresponding numbers in Section 7, Reference.