RCFA Eliminates Repeat Failures

When assets, processes, or procedures are not working, a root cause failure analysis is the best way to solve the problem.

Root Cause Failure Analysis (RCFA) is a data-driven methodology designed to identify the root cause, not symptoms, of what started an issue and use that information to develop and implement change that prevents it from happening again.

RCA (Root Cause Analysis) identifies factors that resulted in the failure. RCFA finds the root cause of the failure. The approach can be used on assets, processes, services, and product investigations. Most people use the terms RCA and RCFA interchangeably. The opportunities and challenges are similar in all types of facilities.

As with many reliability and maintainability functions, doing RCFA basics well and following a standardized process will lead to ongoing improvements. There are several reasons facilities have not realized a fully functional RCFA process:

• Failure to use a clearly defined problem statement

• Not using a standardized information-collection process that distinguishes between fact and opinion

• Not holding people accountable to complete the RCFA process with a follow-up to confirm that the fix was the correct root cause

• Jumping too quickly to implement a fix based on previous experience

• Not having sufficient data or quality data

• Focusing on the equipment while ignoring contributing culture issues

• Not having enough system thinking and team cross-functional input, typically because a single person is very knowledgeable about the equipment and is impatient

• Not performing enough predictive/condition-based maintenance to find and eliminate random-failure events

• Too many people having an “it’s not my issue” attitude versus a small-team, plant-floor, continuous-improvement approach that enables a “problem-solving mentality.”

These tools and techniques should be employed to support the RCFA process:

• 5 Whys: Repeatedly ask why until you get to a root cause. Most people are familiar with this and use it on the plant floor.

• Pareto chart: Data analysis (charting) tool that identifies the most important factors (about 20%) that contribute to a majority of the problems.

• Fishbone diagram: This technique, also known as a “cause and effect” or “Ishikawa” diagram, is a good visual method to categorize the potential causes of a problem. There are dozens of templates for various industries with the most common categories being
environment, machines, measurement, methods, and people. The templates allow you to change/add categories as needed.

When performing RCFA, understand the basics and dive into the various levels of issues caused by machine/equipment breakdowns, human error, dysfunctional/hidden issues, and process/systems. Know when to perform an RCFA. Use multiple RCFA-related tools and techniques, such as Change Analysis, Barrier Analysis, FMEA, Logic Tree, Fault Tree, Process Mapping, and Correlation & Scatter Diagrams, to get to the real root cause.

The next Root Cause Analysis course taught at UT-Knoxville (utk.edu) is September 10 to 12, 2024. More than twelve different tools/techniques will be covered. EP

Based in Knoxville, Dr. Klaus M. Blache is director of the Reliability & Maintainability Center at the Univ. of Tennessee, and a research professor in the College of Engineering. Contact him at kblache@utk.edu.