Failure Mode and Effects (and Criticality) Analysis
A failure mode and effects analysis (FMEA) or failure mode, effects, and criticality analysis (FMECA) is a reliability evaluation and design review technique that examines the potential failure modes within a system or function, or lower level in the system/function hierarchy, to determine the effects of failures on system/function performance. Each failure mode is classified according to its impact on system/function operating success and personnel safety.
FMEA/FMECA uses an inductive logic on a "bottom up" system analysis. This approach begins at the lowest level of the system/functional hierarchy and traces up through the system/functional hierarchy to determine the end effect on system/function performance.
The maximum benefit of performing a FMEA/FMECA is realized from an early application in the system's life cycle rather than after the system's design is finalized.
- Determines the effects of each failure mode on system performance.
- Emphasizes identification of single-point failures.
- Provides data for developing fault tree analysis and reliability block diagram models.
- Provides a basis for identifying root failure causes and developing corrective actions.
- Facilitates investigation of design alternatives to consider high reliability at the conceptual stages of the design.
- Aids in developing test methods and troubleshooting techniques.
- Provides a foundation for qualitative reliability, maintainability, safety and logistics analyses.
- Uses a documented, systematic, and uniform method.
- Can provide an early identification of single failure points and system interface problems.
- Provides a mechanism for verifying that switching between redundant elements is not jeopardized by postulated single failures.
- Provides an effective method for evaluating the effect of proposed to the design on mission success.
- Provides the criteria for early planning of tests to characterize the weaknesses of the design.
- Provides a basis for the safety analysis that is done as part of evaluating the safety characteristics of the design.
- Provides a basis for operational troubleshooting and for locating performance monitoring and fault-detection devices within the system.
- Highlighting areas needing corrective action.
- Ranking failures according to severity of equipment operation and personal safety.
- Identifying reliability and safety critical components.
- Visibility of system interface features and problems
- Locating performance monitoring and fault sensing test equipment or test points.