Fault tree analysis of the EBR-II reactor shutdown system

Conference · Tue Dec 01 04:00:00 EST 1992

OSTI ID:10117657

Kamal, S A; Hill, D J

As part of the level I Probabilistic Risk Assessment of the Experimental Breeder Reactor II (EBR-II), detailed fault trees for the reactor shutdown system are developed. Fault tree analysis is performed for two classes of transient events that are of particular importance to EBR-II operation: loss-of-flow and transient-overpower. In all parts of EBR-II reactor shutdown system, redundancy has been utilized in order to reduce scram failure probability. Therefore, heavy emphasis is placed in the fault trees on the common cause failures (CCFs) among similar mechanical components of the control and safety rods and among similar electrical components in redundant detection channels and shutdown strings. Generic beta-factors that cover all types of similar components and reflect redundancy level are used to model the CCFs. Human errors are addressed in the fault trees in two major areas: errors that would prevent the automatic scram channels from detecting the abnormal events and errors that would prevent utilization of the manual scram capability. The fault tree analysis of the EBR-II shutdown system has provided not only a systematic process for calculating the probabilities of system failures but also useful insights into the system and how its elements interact during transient events that require shutdown.

• Research Organization: Argonne National Lab., IL (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 10117657
• Report Number(s): ANL/CP--75950; CONF-930116--24; ON: DE93004803
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210500
22 GENERAL STUDIES OF NUCLEAR REACTORS
220600
220900
CONTROL ELEMENTS
EBR-2 REACTOR
EXCURSIONS
FAILURES
FAULT TREE ANALYSIS
LOSS OF FLOW
POWER REACTORS
BREEDING
REACTOR CONTROL SYSTEMS
REACTOR SAFETY
REACTOR SHUTDOWN
RELIABILITY
RESEARCH
TEST
TRAINING
PRODUCTION
IRRADIATION
MATERIALS TESTING REACTORS
SCRAM
TRANSIENTS