Contribution of functional analysis to failures deductive analysis

Before studying the dependability of a system, it is necessary to know its architecture and the way it works. Though the functional analysis stage is fundamental, since it affects the success of preventive studies of faults, few efforts have been devoted to it. In the same way, there is very little literature about the building process of fault trees. The development stage of fault trees generally depends more on analysts´ expertise than on a rational and scientific approach. In this paper the authors suggest a methodological approach based on functional analysis that allows the building of the fault tree of unwelcome events. This approach rests on a detailed analysis of systems in order to set up a structured and hierarchical study of their faults. Through its rationalised expert approach, it enables analysts to be as exhaustive as possible as to the study of disruptions affecting systems operating process