In last week’s Friday Fact, I mentioned a few tools that can be used to perform risk analysis. One of these is the FMEA, or Failure Mode and Effects Analysis. This tool is excellent for evaluating and forecasting the possibility of a failure mode during the life of a product.
FMEA is a systematic method of identifying and preventing product and process problems before they occur. Originally modelled as an off-shoot of Military Procedure MIL-P-1629, titled “Procedures for Performing a Failure Mode, Effects and Criticality Analysis” (issued in 1949), it was originally used to determine the effect of system and equipment failures. NASA further developed this tool in the 1960s to specifically look at safety issues. Today, it is the most widely accepted method of evaluation used throughout military and manufacturing industries. In the medical device industry, FMEA is part of the required validation and verification risk management used during the design process, as well as throughout production of the device.
There are two kinds of FMEAs: design and process. The dFMEA is used while a new product/process is in development; pFMEAs are performed after the process has moved into production. “Briefly stated, an FMEA is a long matrix that identifies potential failure modes, potential effects of failures, severities, potential causes, occurrences, and current process controls and detections. Taken together, these generate a risk priority number (RPN). The RPN is the multiplication of the severity, occurrence and detection.” (“No Finish Line”, Quality Progress magazine, April 2015)
A team is assembled to explore the potential failure modes of a specific process. This team should consist of at least a subject matter expert, subject matter novice, and a team lead – it may also include representatives from Quality Assurance and the customer. Typical team sizes are 4-6 people. After the team has identified potential issues, and scored the RPN, actions are then taken to sufficiently improve the product/process/safety of the items identified in order to reduce the RPN.
One of the strengths of this method is the ability to identify where and how a process might fail, as well as actions that need to be taken to prevent such an occurrence from happening. Another positive aspect of FMEAs is that it does not require a previous bad experience to solve potential issues. This approach can make an existing system more robust.