It will probably come as little surprise that something called failure modes and effects analysis (FMEA) evolved at the National Aeronautics and Space Administration, an environment where the interest in preventing failures is extremely high. FMEA was later popularized by the automobile industry and in recent years has become more widespread among Six Sigma practitioners. It is now seen routinely even in transactional functions.
What Is FMEA?
FMEA is a system for analyzing the design of a product or service system to identify potential failures, then taking steps to counteract or at least minimize the risks from those failures.
The FMEA process begins by identifying “failure modes,” the ways in which a product, service or process could fail. A project team examines every element of a service, starting from the inputs and working through to the output delivered to the customer. At each step, the team asks “what could go wrong here?”
Here are a few simple examples of failure modes related to the process of providing hot coffee at a truck stop:
•One of the inputs to that process is a “clean coffee pot.” What could go wrong? Perhaps the water in the dishwasher is not hot enough, so the coffee pot is not really clean.
•The first step in the process is to fill the brewing machine with water. What could go wrong? Perhaps the water is not the right temperature or the staff puts in too much or too little.
•An output from the process is a hot cup of coffee delivered to the customer. What could go wrong? The coffee could get too cool before it is delivered.
Of course, all failures are not the same. Being served a cup of coffee that is just hot water is much worse than being served a cup that is just a bit too cool. A key element of FMEA is analyzing three characteristics of failures:
1.How severe they are
2.How often they occur
3.How likely it is that they will be noticed when they occur
Typically, the project team scores each failure mode on a scale of 1 to 10 or 1 to 5 in each of these three areas, then calculates a Risk Priority Number (RPN):
RPN = (severity) x (frequency of occurrence) x (likelihood of detection)
The idea is to focus improvement efforts on the failures that have the biggest impact on customers. The highest scoring failure modes are those that happen a lot, that are bad when they happen, and/or that are unlikely to be detected. Difficult-to-detect errors obviously are more likely to get through to customers.
The team then completes the FMEA analysis for the highest-scoring failure modes and for any that get the highest severity scores, even if they do not score that high overall. Obviously, a business wants to make sure any possible disaster is prevented, even if it is unlikely to occur. “Completing the analysis” means looking at the potential causes for the error mode, identifying ways to detect the problem, developing recommended actions, and assigning responsibility for monitoring the process and taking action when warranted.