Using Fault Tree Methodologies in Availability Improvement Studies at Southern Company Services

This paper describes the methodology used in two availability improvement studies that made extensive use of fault trees. The studies were done for Georgia Power Company´s Edwin I. Hatch Nuclear Plant, a General Electric boiling water reactor. The studies combined the classical methods of performing a reliability analysis; i.e., studying plant records of equipment performance, with the relatively newer fault tree methodologies. The fault tree provides a graphic, organized structure whereby the failure behavior of a system can be studied from a qualitative as well as a quantitative standpoint.