After you create an Action in a System Reliability Analysis, you can assign a single Risk or multiple Risks to that Action. When you assign a Risk to an Action, a link is created between a System Risk Assessment record, which stores the GUID of the mitigated Risk in the Risk GUID field, and the Action. This allows the Action to mitigate the Risk. An Action may mitigate a Risk by changing certain properties, such as failure consequences or the failure distribution, of the Risk.
Actions mitigate Risks in different ways depending on the type of Action that is assigned to the Risk. The different types of Actions mitigate Risks in the following ways:
- Preventive Maintenance Action: Can mitigate the Time to Fail (TTF) distribution of the Risk by increasing the maximum operating time of the Risk, as defined by the fields in the Distribution record that defines the TTF distribution associated with the Risk. For example, the Replace Seal Action in Scenario B of the System Reliability Analysis Example mitigates the Seal Failure Risk by creating more operating time by replacing the existing seals, which have a smaller amount of operating time, with new seals that have a larger amount of operating time.
- Condition Monitor or Inspection Action: Can mitigate the consequences of failure by fixing potential failures before they occur. This allows proactive repairs, or planned corrections, to be made to the system instead of fixing a failure using an unplanned correction. Planned corrections can consume less Resources and lower the costs of a Scenario. For example, the Vibration Analysis Action in Scenario B of the System Reliability Analysis Example mitigates the Bearing Failure Risk by identifying a potential Bearing Failure and executing a planned correction, which requires less Resources and less Resource usage than executing an unplanned correction.
- Special Action: Can mitigate the failure consequences of the Risk, as defined in the Fixed Unplanned Correction Cost field of the System Risk record, and the TTF distribution, as defined by the Distribution record that represents the TTF distribution associated with the Risk. For example, the occurrence of the Redesign Impeller Action in Scenario B of the System Reliability Analysis Example mitigates the Impeller Failure by reducing the fixed unplanned correction cost and extending the TTF distribution of the Impeller Failure Risk.
Note: An Action does not have to mitigate a Risk, but associating an Action with a Risk and mitigating the Risk creates a more reliable system.
