DFMEA stands for Design Failure Mode and Effects Analysis, and PFMEA stands for Process Failure Mode and Effects Analysis. They are both FMEA and use the same methodology.
So what is the difference between DFMEA and PFMEA? The main difference is objective. While DFMEA focuses on design problems, PFMEA focuses on process problems.
Example: DFMEA for the pencil design and PFMEA for the pencil production process. A same problems (failure or failure effect) can be seen in DFMEA and PFMEA: broken pencil with regular usage.
But DFMEA and PFMEA will focus on the different causes
- DFMEA: Incorrect material is specified (wood type is weak)
- PFMEA: Incorrect material is used by the operator (choose the wrong type of wood in production)
To manage this problem in both DFMEA and PFMEA, the actions are also different
- DFMEA: Material test for pencil design before design approval.
- PFMEA: Instruction, mistake proofing, or inspection applied in production to prevent or detect the wrong material used by the operator
However, DFMEA should cover all the potential failures that can occur in production if the failures are the result of bad design. For example, the wrong part is assembled because it has a similar shape to the correct part. If DFMEA cannot eliminate or reduce the risk of these failures (by applying poka-yoke in design, for example), PFMEA should take care.