The 5 Whys: A Simple Tool to Aid in Accident Investigation

July 7, 2023

This blog post was written by Marc Dunker, a League of Minnesota Cities loss control consultant. 

Accident review or investigation is an effective means of determining why workplace injuries occur, and it can be also be a tool for reducing reoccurrence. But how do you fit that process into an already heavy workload? Keep it simple and to the point by utilizing a root cause analysis tool such as the “5 Whys” method.

The “5 Whys” is about as simple a root cause investigation tool as I have seen. Read this PDF for more details on the 5 Whys method and a worksheet to help you conduct an analysis.

Find the facts, not the fault

A worksheet to guide a root cause investigation using the 5 Whys method.
Download this worksheet to help you use the 5 Whys method during an accident investigation.

The 5 Whys method is simple; you literally just start asking “why”-based questions. In the example in the PDF linked above, an employee has crushed his finger in a drive belt pulley. The example leads us to the conclusion that the injury could have been prevented if a machine checklist had been used as part of a hazard assessment. Notice how we didn’t blame the worker?

In some cases — in fact, in many cases — you may find you ask more than five whys and you get more than one possible root cause. That’s okay! The objective is to learn what happened and how to prevent it from being repeated — so ask, listen, and learn. The key to a successful review is to find the facts, not the fault. Remember, this exercise is meant to determine what caused an incident, not who caused it.

Can you see how the 5 Whys method could help you gain insight into your workplace accidents and near misses? This tool can also help lead a conversation about an injury without causing the injured worker to feel defensive or like he is in the hotseat. It’s a tool anyone can use regardless of their loss prevention or safety experience. It can reduce injuries in the workplace, improve the safety culture of your city, and lower your insurance costs. Not to mention, it helps fulfill your MnOSHA AWAIR program requirement of accident investigation.

Contact your loss control consultant for help

If you need help applying the “5 Whys ” in your city, or if you need help with other safety or loss prevention processes, contact your League of Minnesota Cities loss control consultant. We’re happy to help.