Basic Fault Tree Analysis Technique

The fault tree analysis (FTA) technique is proven to be an effective tool for analyzing and identifying areas for hazard mitigation and prevention while in the planning phase or anytime a systematic approach to risk assessment is needed. FTA is used as an integral part of a probabilistic risk assessment. This chapter covers the very basics of FTA. The NASA Fault Tree Handbook with Aerospace Applications is a complete guide to FTA. Fault trees show graphically the interaction of failures and other events in a system. Basic events are depicted at the bottom of the fault tree and are linked via logic symbols (known as gates) to one or more of the top (TOP) events. These TOP events represent hazards or system failure modes for which predicted reliability or availability data is required. Typical TOP events might be: total loss of production, explosion, toxic emission, and safety system unavailable.