Risk Assessment: Tools, Techniques, and Their Applications

14.3 Fault Tree Construction

The goal of fault tree construction is to model the system conditions that can result in the undesired event. The analyst must acquire a thorough understanding of the system before beginning the analysis. A system description should be part of the analysis documentation. The analysis must be bounded, both spatially and temporally, in order to define a beginning and endpoint for the analysis.

The fault tree is a model that depicts graphically and logically represents the various combinations of possible events, both fault and normal, occurring in a system leading to the top event. The term event denotes a dynamic change in state that occurs to a system element. System elements include hardware, software, human, and environmental factors.