Common cause failures and cascading failures in technical systems: Similarities, differences and barriers

Many technical systems continue to increase in size and complexity, with more interactions and interdependencies between components. Dependent failures, such as common cause failures and cascading failures, are becoming important concerns to system reliability. Both failure types may lead to the unavailability of multiple components at the same time or within a short time interval. Although many researchers have studied common cause failures and cascading failures respectively, there is little comparison of the two concepts. This paper investigates the similarities and differences of these two failure groups, with focus on the conditions and nature of initiations and propagation of such failures. Moreover, a comparison is also made about suitable barrier strategies that can either prevent or reduce the consequences of failure. The paper concludes the study with a demonstration of reliability modeling for common cause- and cascading failures.