Useful Resources

TapRooT Website
TapRooT is a trademarked root cause analysis tool / system which has been adopted by many big companies around the world.
Wikipedia entry on Root Cause Analysis
Wikipedia provides some useful insight into different root cause analysis tools.

Root Cause Analysis

The most effective solution to a problem addresses the root causes rather than merely addressing symptoms.  Root causes are the underlying reasons why a problem occurs.  Root cause analysis (RCA) seeks to determine not only what occurred or how it occurred, but also why it occurred.  By directing corrective action at root causes, you can reduce the likelihood that the problem will recur.

Take for example an incident where an operator accidently opens the wrong valve during start-up, causing a large spill of material.  A superficial analysis of this incident may conclude that human error was the cause, and recommend counselling and re-training for the individual involved.  A more thorough root cause analysis, however, may find underlying conditions that contributed to the human error – eg. poor labelling of the valves, poor lighting in the area, task being done in a hurry because they were short-staffed, unclear procedure etc.  Addressing these underlying causes will help reduce the risk of this or similar incidents happening again.

Root cause analysis is not a single methodology; there are many different tools and processes available. Some common techniques include:

  • 5 Whys
  • Failure mode and effects analysis (FMEA)
  • Ishikawa or Fishbone diagram
  • Causal factor tree analysis

All these techniques aim to help you drill down below the obvious symptoms to discover the underlying and controllable reasons for the problem.  Many involve using charts or diagram to help visualise the issues.

A general process for performing RCA involves the following steps:

  • Define the problem.
  • Gather data and evidence.
  • Identify all issues that contributed to the problem.
  • Track issues back to their most fundamental cause, and identify those that are within the organisation’s control.
  • Develop and implement solutions.