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The relationship between ICAM and 5 Whys

The Incident Cause Analysis Method (ICAM) is a popular and widely applied workplace incident investigation method. It has come a long way since its BHP evolution (original author) in 1998 and has been further developed by Safety Wise Solutions (Safety Wise) through a suite of manuals and training packages. Today Safety Wise has trained more than 70,000 people globally in ICAM in 7 languages and across 43 countries.

However, the usefulness of ICAM as a tool is only as good at its ability to respond to industry needs and requirements as well as keep up to date with contemporary incident investigation practice.

This article clarifies a recent update to the ICAM process as well as addressing one common misconception about ICAM: namely its relationship to 5 Whys. Some users believe that conducting a 5 Whys analysis is a necessary step when conducting an ICAM investigation. Safety Wise believes this to be a redundant step and here we explain why.


The 5 Whys technique is a structured question asking technique that is typically applied to each event sequence in a timeline to identify a potential root cause.

The basic premise of the approach is to repeatedly ask the question ‘Why?’ until an organisational deficiency/root cause is identified. The technique was originally developed by Sakichi Toyoda and was used by the Toyota Motor Corporation in managing production issues, however, the technique can also be used in incident investigations.

The ‘5’ in 5 Whys is based on empirical observations of the number of times ‘Why?’ must typically be asked to resolve the problem or identify the safety issue, though in practice it can be more or less than the suggested 5 times.

The following example illustrates the 5 Whys process.

Of note, the 5th why in the above example identifies a root cause, which can be linked to one of the 16 organisational factor types in ICAM.


The 5 Whys technique is useful in that it forces the investigator(s) to separate symptoms from causes and root causes. For example, the technique helps to look beyond human error as a simplistic cause and look further afield at the underlying reasons that led to the error(s). This can assist in preventing band aid solutions.

However, there are some limitations to the 5 Whys approach:

  • There are no hard and fast rules about the lines of questioning to explore.

  • How many times should ‘Why?’ be asked can be unclear.

  • Outcomes are not always repeatable.

  • Investigators tend to stop at symptoms (or indicators) and not fully explore the underlying system deficiencies.

  • The technique limits the scope of the investigation to the occurrence.

These limitations can be significant, and readers are directed to a comprehensive critical review of 5 Whys published by Alan Card in 2017 in the BMJ Quality and Safety Journal.

In summary, the main issue with 5 Whys is that it does not have the sophistication to allow for comprehensive analysis of more complex incident investigations and therefore is only generally recommended for low severity risk level incidents such as minor injury, first aid, minor equipment damage etc.

The recommended scope and types of investigations are shown below. Where the risk level is minor a 5 Whys or ICAM lite is recommended. At moderate to critical risk levels, ICAM is recommended – this does NOT have to include 5 Whys as a step.

Of note when Safety Wise conducts independent investigations for its clients, we do not use 5 Whys as we typically are conducting investigations into high potential, significant injury or fatality/multiple fatality events. ICAM is a better analysis process for events that are more complex in nature. Our incident investigation report template does not even contain a 5 Whys section for this reason.


So why do some people mistakenly believe that to conduct an ICAM investigation you also have to perform a 5 Whys? I blame this on a BHP legacy issue. In other words, this is what was originally a requirement for ICAM investigations within BHP and by default was adopted by other organisations. It is only in the last few years, that Safety Wise has sought to clarify that 5 Whys is an optional extra when an ICAM investigation is being conducted.


Conducting BOTH a 5 Whys and ICAM analysis in the same investigation is considered redundant for the following reasons:

  • 5 Whys is designed to produce a root cause or organisational factor. But the same organisational factors are produced via ICAM – hence a double up.

  • Conducting a 5 Whys as part of timeline development may take several hours for the investigation team to complete. These are hours that would be better spent on getting the transition from the PEEPO data collection to the ICAM analysis step right. Essentially the 5 Whys step becomes unnecessary.

In summary, ICAM users are advised to conduct either a 5 Whys investigation (for low-risk events) or an ICAM for higher-level risk events. Doing both in the same investigation is so 1998! It’s time to move on people.

In consideration of the above, Safety Wise is currently updating its signature 2-day Lead ICAM course which amongst other updates, clarifies the relationship between 5 Whys and ICAM. 5 Whys is not part of the course material unless a client specifically requests this.

The new updated Lead ICAM course is expected to be rolled out around late 2021. But for those 5 Whys lovers – don’t panic we also offer a standalone 5 Whys course!

Interested in Knowing More?

Further information on Safety Wise’s Incident Cause Analysis (ICAM) Training is available from our website:

Additional ICAM Related Services

Safety Wise also offers the following additional services for sites that adopt the ICAM investigation analysis method:

  • Quality review of incident investigations using ICAM

  • Trend analysis of organisational factors contributing to serious incidents

  • Participation in investigations as an external / independent party


ABOUT THE AUTHOR- Dr Graham Edkins (Business Development Manager)

Graham was involved with the original development and rollout of the ICAM process while representing Qantas as Head of Human Factors in the late 1990's. Nearly 20 years later Graham's belief in the practical utility and continual improvement of ICAM as a bespoke incident investigation analysis tool for any workplace has not wavered.

Graham's commitment to improving the quality of incident investigations for high-risk industries originally stemmed from safety investigation roles in rail, aviation and for the Commonwealth Government as a Transport Safety Investigator. This commitment continued during his time as the Rail Safety Regulator for Victoria and as a Senior Executive with the Civil Aviation Safety Authority. What these roles have taught Graham is that it's possible to develop error-tolerant systems through data driven but practical strategies.

In his role as Business Development Manager for Safety Wise, Graham is involved in the ongoing improvement of the ICAM product and driving the quality application of its use within client organisations. With a focus on delivering practical and sustainable results, Graham is highly sought after as an expert on safety behaviour change, error management and the proactive application of ICAM.


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