Fault Tree Analysis (FTA) can be used to help determine component failure modes. As-sume the top level event of the Fault Tree is how a component may fail to meet its intended function. Then the next level down will identify the causes as part failure modes.
Enter the potential failure mode(s) for each function listed in Column 9. Potential failure modes should be described in �physical� or technical terms, not as a symptom noticeable by the operator. (To track the failure modes, it may be beneficial to assign them a number.) Do not enter trivial failure modes, i.e., failure modes that will not, or cannot, occur.
General types of failure modes for the functional approach include:
Failure to operate at the prescribed time
Failure to stop operating at the prescribed time
Intermittent operation
Wear out
General types of failure modes for the hardware approach include: