What Is FMEA?
Failure Mode and Effects Analysis (FMEA) is a structured, bottom-up methodology for identifying all the ways in which an asset or system can fail — and systematically evaluating the consequences of each failure mode. Originally developed in the aerospace industry in the 1950s, FMEA has since become one of the most widely applied tools in reliability engineering across virtually every asset-intensive sector.
FMECA (Failure Mode, Effects, and Criticality Analysis) extends FMEA by adding a quantitative criticality assessment — ranking each failure mode by its probability and severity to produce a prioritised action list.
The FMEA Process
| Step | Description |
|---|---|
| 1. Define Scope | Identify the system, subsystem, or component to be analysed |
| 2. Identify Functions | Document what the system is required to do and to what standard |
| 3. Identify Failure Modes | List every way in which each function could fail |
| 4. Identify Effects | Determine the consequences of each failure mode at system level |
| 5. Identify Causes | Determine the root causes that could lead to each failure mode |
| 6. Assign Severity, Occurrence, Detection Ratings | Score each failure mode to calculate Risk Priority Number (RPN) |
| 7. Develop Actions | Define recommended preventive, predictive, or redesign actions for high-RPN items |
FMEA vs RCM: Complementary Tools
FMEA and RCM are closely related but not identical. RCM is a decision-making process that uses failure mode analysis as its input. FMEA is the analytical tool that provides that input. Many practitioners use FMEA as the analytical foundation within a broader RCM process — leveraging FMEA's structured failure mode identification and FMECA's criticality ranking to prioritise where RCM decision-making should focus.
Common Applications
FMEA/FMECA is applied across a wide range of contexts: maintenance strategy development; design review and new asset commissioning; safety case development; management of change assessments; and reliability improvement programmes. Optimal's reliability engineers are experienced practitioners in FMEA/FMECA methodology, having applied it across oil and gas, mining, power generation, manufacturing, and nuclear sectors.
Ready to apply these insights? Contact Optimal at enquiries@optimal.world or book a discovery call to speak with one of our experts.