Failure Modes and Effects Analysis

(see the PFMEA page for a Process Failures Modes & Effects template, instructions, and downloads)

FMEA (Failure Modes & Effects Analysis) was developed long before the DMAIC framework was created and is a powerful tool for preventing both design and process failures.

There are two distinct types of FMEA’s:  Design (DFMEA) and Process (PFMEA).

  • Design FMEA’s focus on how each element in the design could fail, starting with higher level systems, then moving into sub-systems and components.  Each potential failure is assessed using a Risk Priority Number (RPN), and design countermeasures are implemented for RPN values above a certain threshold value (more the RPN calculation below).
  • While DFMEA’s focus on how the design could fail to meet customer expectations, PFMEA’s focus on each manufacturing process step that will manufacture the design, and how each step could potentially fail to manufacture a product within specification limits.  The PFMEA approach also works extremely well for any process that delivers a specific outcome for a customer.  For example, a medical team might use a process flow diagram and PFMEA to quantify the risks associated with delivering the wrong medication to a patient.

Our PFMEA link shows the basic steps for conducting PFMEA’s, and the following DFMEA link provides a good overview of the DFMEA process.