A review of defences against common cause failures in reactor protection systems

Redundancy is essential for achieving fault tolerance and higher dependability attributes. Redundancy by means of replication of identical units is widely used and under the assumption of random failures, it proves to be beneficial also. But common cause failures (CCFs) are threat to such redundancy schemes. With the increasing use of computer-based/electronic programmable systems in critical applications, CCFs are becoming major contributors to systems failures.