Why do we still have major process safety accidents?
I had an interesting argument about root cause analysis and process safety. The person I was arguing with thought that 5-Whys was a good technique to use for process safety incidents that had low consequences.
Let me start by saying that MOST process safety incidents have low actual consequences. The reason they need to be prevented is that they are major accident precursors. If one or more additional Safeguards had failed, they would become a major accident. Thus, their potential consequences are high.
From my previous writings (a sample of links below), you know that I consider 5-Whys to be an inferior root cause analysis tool.
- Why Did The Robot Stop? (Comparing 5-Why Results with TapRooT® Root Cause Analysis Results)
- A Critical Look at Root Cause (page 32)
- What’s Fundamentally Wrong with 5-Whys?
- Teruyuki Minoura (Toyota Exec) Talks About Problems with 5-Whys
If you don’t have time to read the links above, then consider the results you have observed when people use 5-Whys. The results are:
- Inconsistent (different people get different results when analyzing the same problem)
- Prone to bias (you get what you look for)
- Don’t find the root causes of human errors
- Don’t consistently find management system root causes
And that’s just a start of the list of performance problems.
So why do people say that 5-Whys is a good technique (or a good enough technique)? It usually comes down to their confidence. They are confident in their ability to find the causes of problems without a systematic approach to root cause analysis. They believe they already know the answers to these simple problems and that it is a waste of time to use a more rigorous approach. Thus, their knowledge and a simple (inferior) technique is enough.
Because they have so much confidence in their ability, it is difficult to show them the weaknesses in 5-Whys because their answer is always:
“Of course, any technique can be misused,
but a good 5-Whys wouldn’t have that problem.”
And a good 5-Whys is the one THEY would do.
If you point out problems with one of their root cause analyses using 5-Why, they say you are nitpicking and stop the conversation because you are “overly critical and no technique is perfect.”
Of course, I agree. No technique is perfect. But some are much better than others. And the results show when the techniques are applied.
And that got me thinking …
How many major accidents had precursor incidents
that were investigated using 5-Whys and the corrective
actions were ineffective (didn’t prevent the major accident)?
Next time you have a major accident, look for precursors and check why their root cause analysis and corrective actions didn’t prevent the major accident. Maybe that will convince you that you need to improve your root cause analysis.
If you want to sample advanced root cause analysis, attend a 2-Day or a 5-Day TapRooT® Course.
The 2-Day TapRooT® Root Cause Analysis Course is for people who investigate precursor incidents (low-to-moderate consequences).
The 5-Day TapRooT® Advanced Root Cause Analysis Team Leader Course is for people who investigate precursor incidents (low-to-moderate consequences) AND perform major investigation (fatalities, fires, explosions, large environmental releases, or other costly events).
See the schedule for upcoming public courses that are held around the world HERE. Just click on your continent to see courses near you.