Failure Mode and Effects Analysis (FMEA) is a structured, step-by-step method used to identify and evaluate potential failures in a product, process, or system before they occur. It focuses on how something can fail (failure modes), why it might fail (causes), and what happens if it fails (effects).
In manufacturing and operations, FMEA is typically performed by a cross-functional team and follows a standardized sequence:
- Define the scope of the product, process, or system being reviewed.
- List functions and requirements for each step, component, or subsystem.
- Identify potential failure modes for each function (ways it might not meet requirements).
- Determine potential effects of each failure mode on the customer, process, or downstream operations.
- Identify potential causes and existing controls that detect or prevent each failure mode.
- Assign ratings for severity, occurrence, and detection, then calculate a risk priority metric (such as Risk Priority Number, RPN).
- Prioritize failure modes based on the ratings and define specific actions to reduce risk.
- Update the analysis after actions are implemented, revising ratings and documentation.
FMEA can be applied at different levels, such as design FMEA (DFMEA) for product designs and process FMEA (PFMEA) for manufacturing or service processes. It is often used alongside Root Cause Analysis (RCA): RCA investigates why an actual failure occurred, while FMEA anticipates and ranks potential failures so they can be addressed systematically.