Definition(s)
Common-Cause Failure
Failures of different items resulting from the same direct cause, occurring within a relatively short time, where these failures are not consequences of another. NOTE Components that fail due to a shared cause normally fail in the same functional mode. The term common mode is, therefore, sometimes used. It is, however, not considered to be a precise term for communicating the characteristics that describe a common-cause failure.
Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global Standards
Common Cause Failure
Failures of different items resulting from the same direct cause, occurring within a relatively short time, where these failures are not consequences of each other.
Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global Standards
Common Cause Failure
failures of different items, resulting from a single event, where these failures are not consequences
of each other
Note 1 to entry: It is generally accepted that the failures occur simultaneously or within a short time of each other.
Note 2 to entry: Common cause failures can lead to common mode failures.
Note 3 to entry: Common cause failures reduce the effect of system redundancy.
Note 4 to entry: Explicit and implicit CCF are defined in 5.4.2.
Source: ISO/TR 12489:2013(E) Reliability modelling and calculation of safety systems. Global Standards