ABSTRACT
Faults are analyzed through a graphical representation of causality known as Fault Tree Analysis (FTA). Faults are used to analyze the effect of failures on the system, subsystem, or operating environment (i.e., to facilities, equipment, or personnel). Failures are associated with a quantitative analysis of the design of the system. Hazards are assessed qualitatively, and must be analyzed and either eliminated or reduced to an acceptable level of risk through a mitigation process. The relationship between faults, failures, and hazards may best be understood as follows: not all faults are failures and not all failures present a hazard to the system.
