Fault Tree Analysis

This chapter uses the fault tree approach to analyze in more detail the basic event combinations that could lead to the top event, to assess the probability that such an event might occur and to reflect on the positioning of the safety barriers. The analysis via fault trees is a deductive method. The authors are concerned with identifying all the combinations that could lead to that event. A reliability diagram or “success diagram” consists of representing a system by blocks generally corresponding to components, functions or sub-systems. The chapter uses a model-based approach for the risk analysis that facilitates the building of the fault tree. The common cause failure (CCF) analysis is a very important aspect that must be considered in risk analyses because CCF significantly increases the vulnerability of a system.