Preventive action, recommendations development process

The process of developing recommendations is summarized in Figure 10-1. Starting with the set of multiple causes determined previously in Chapter 9, each cause is evaluated individually to consider actions that would prevent (or satisfactorily mitigate) a recurrence. Ideally, each recommendation should cover just one item and spell out precisely what action is recommended. 

Critical items List The purpose of the FMEA is to identify and evaluate failure modes and the possible system effects of those failures. Since the potential for undesirable effects must be eliminated or controlled, the FMEA also provides recommended actions that must be taken to accomplish this goal. As part of this analysis process, the FMEA identifies any and all items within the system that, if a failure were to occur, would have a critical effect on the operation of that system. Therefore, to facilitate evaluation and analysis of these system effects, a critical items list is developed. The list provides detailed descriptive information on each item. It will explain its overall function within the system, as well as the function of any components that may make up that item. The failure mode determined as critical is then listed along with the potential effect(s) of such a failure. If an item on the critical items list is to be accepted as is, then acceptance rationale must be provided. Such rationale may include an explanation of any existing or planned design limitations that will prevent the failure during actual system operations, or the provision of excessive factors of safety that will render such fail-ure(s) extremely improbable. Another area for evaluating acceptance is the history, or lack thereof, and any known failures of systems similar in nature and operation. 

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