Early in plant life,
Westinghouse HFB breakers were installed in various systems onsite, including safety-related applications. The design life of these breakers was 20 years, according to
Westinghouse. A portion of these breakers remained in-use at LaSalle and were installed more than 30 years ago. The licensee monitored breaker performance and tested these breakers routinely. Records show that failures of this type of breaker were researched and all of the previous failures at LaSalle have been attributed to manufacturing defects. While the lack of degradation-related failures for these breakers supported the disposition under the 50.65 Maintenance Rule, at this time, it is not clear that a lack of such failures provided adequate basis for an extension to the previously established design life. This issue is unresolved pending the inspectors review of additional information regarding the details of the components qualifications as noted in the original purchase order, in order for the inspectors to evaluate the acceptability of the licensees current method of extending the life of the component.
