FMEA | Failure Mode & Effects Analysis
Definition
FMEA is short for Failure Mode and Effects Analysis. FMEA is an analytical quality method that is mainly used in the automotive industry (including supplier industries), but is now also used in other industries in the regulated environment (such as medical technology or aviation) to prevent errors.
The aim of the FMEA is to avoid errors in advance, especially if the consequences of the error can affect life and limb. This means that possible causes of defects are identified in the early stages of product development, the consequences of defects are evaluated, and avoidance and detection actions are defined. This helps companies to avoid costly product modifications or even product recalls. The later defects are discovered, the more time-consuming and expensive it is to correct them.
Key Figures of the FMEA
SOD
Severity, Occurrence and Detection are figures used for risk assessment. Based on evaluation catalogs, integral values are assigned usually between 1 and 10.
RPN
The risk priority number is calculated by multiplying the significance, probability of occurrence and probability of detection:
RPN = S x O x D
The RPN, as the name implies, is used to prioritize all identified risks in order to derive a prioritization of the necessary improvement potentials.
AP
Action Priority is a metric developed as part of the 2019 AIAG/VDA Handbook. This replaces RPN and maps the need for improvement actions - also based on SOD. Based on the action priority, all combinations of B, A and E are considered individually and classified into high, medium and low action priority.
Types of FMEA
- Design-FMEA (DFMEA, partly called Product-FMEA)
- Prozess-FMEA (PFMEA)
- Reverse-FMEA (RFMEA)
- FMEA MSR
- System-FMEA
Norms and Standards
There are many different norms and standards for FMEA, always depending on the context of the application. As product complexity grows, so do the demands on FMEA: each component must be considered individually, and a separate FMEA may be required for each component. Therefore, norms and standards are constantly updated and adapted to new challenges and technologies.
An excerpt of relevant norms and standards:
- DGQ Band 13-11 (automotive industry)
- SAE J1739 (automotive industry)
- AIAG/VDA Handbook (automotive industry)
- IATF-16949 (automotive industry)
- IEC 60812 (elektronic industry)
