Design Failure Modes Effects Analysis - Issues Down, Margins Up

The previous blog outlined the steps in completing a DFMEA; today we will review how to complete a DFMEA template.

Hopefully you'll see how easy it is to consolidate issues, assign rankings and control / mitigate your risks.

The first portion of the template outlines the component name, function, potential failure modes and the potential effects of the failure.

Remember: there maybe more than one step, one failure mode and one effect per component.


Once each step, failure mode and failure  mode effect is listed for each component it is time to assign a severity number (on a relative scale of 1 to 10 - see previous blog for ranking definition).

With the Severity ranking complete the next step is to add the potential causes of each failure and the likelihood of their occurrence (on a relative scale of 1 to 10 - see previous blog for ranking definition).

Once you have the Severity and Occurrence Rankings complete it is time to outline the current process controls for each failure mode and the likelihood of detecting a failure (on a relative scale of 1 to 10 - see previous blog for ranking definition).

The next step is calculating the RPN - Risk Priority Number by multiplying the Severity X Occurrence X Detection.

Next rank the issues by RPN and address the issues from the highest Risk Factor on.

Next, implement some action plans and recalculate the Severity, Occurrence and Detection; the RPN number.  This is an iterative process; get the RPN values down and watch reliability and margins increase.