What is Root Cause Analysis (RCA)?

Root Cause Definition

Root Cause Analysis (RCA) is a set of analyzing and problem-solving techniques targeted at identifying the actual root cause or the reason that caused the problem. The need for RCA stems from the fact that the elimination of the symptoms of the problems is not alone sufficient to address the problem, it has to be addressed at the cause level. If you solve a problem at this root level, it is highly probable that you can prevent its recurrence. A root cause is just what it sounds like, it deals with the “root” of the problem.

 Here is an example:

A tennis court looks sloppy because weeds are growing in the cracks:

• Cutting the weeds only eliminates the symptom as it may grow back.
• Killing/removing the root will eliminate the problem.

If there are more than one root causes discovered after analysis, all the causes have to be addressed at sufficiently satisfactory level for the success of the RCA. A root cause analysis is considered successful when the problem does not recur again such as:

• Filling the crack will prevent the problem from recurring.

RCA is mainly a reactive type of action where the corrective and the analysis takes place after the event or problem happens. The most common approach to solve problems for us is to rush and find an immediate action to solve the problem. This approach will not help in the long run. Here we are not taking any steps to understand the reason why it occurred. We are not taking any steps to prevent it from occurring again. A better approach would be to think beyond the obvious and find an effective way to eliminate the root cause that led to this problem.

Online Training – Online Root Cause Analysis Training

Steps in Root Cause Analysis

• Gather data
  • Define the problem/non-conformance clearly.
  • Once a candidate for RCA (or the problem or the non-conformance) has been identified, gather sufficient information about it.
  • Ask What, How and When about the problem and document it.
• Perform the analysis
  • Use any of the root cause analysis tools & techniques for performing the analysis.
  • Use your logic and choose the best possible way to solve the problem in a simple, effective, and least expensive method. Take care to eliminate the non-probable causes.
• Implement the solution
  • Recommend and implement the best solution.
  • Also, take care to see that these corrective actions do not induce any other or related unforeseen problems. Check that the problem does not recur.
  • Use the data from the learning and analysis of the RCA and use it in the Continual Improvement programs.

Can we really eliminate the Root Cause?

Even though we recognize that it may not be always able to remove the root cause completely, we will most likely be able to prevent its recurrence.

Where is it useful?

RCA can be used in any field across any domain where an organization uses safety-based, production-based, process-based, failure-based, and software-based systems. What are the tools and techniques used in RCA?

The most common tools and statistical techniques used in RCA are:

• Fishbone (Ishikawa) diagram – used during brainstorming, exercises when many possibilities of the resolution exist.
• Pareto chart – used to classify the problems based on the Pareto principle which says 80-% of the problems have 20% of the causes.
• Cause and Effects diagram – used to find the causes and effects of all possible causes of the problem.

Buy ISO 10017 – Guidance on statistical techniques

Examples where RCA can be used or candidates for RCA

• Resolution of health and safety related worker concerns in a manufacturing setting.
• Fixing non-conformances from an audit or review findings in a software development company.
• Seepage of water from the AC duct on the shop floor of a supermarket.
• Number of bugs in software detected in a software test review.