In workplace health and safety, root cause analysis is a valuable process for identifying why an incident, near miss, or non-conformity with the law occurred. Rather than stopping at the immediate or surface-level cause, it helps uncover underlying issues that led to the event. By understanding these root causes, organisations can take effective action to prevent similar incidents in the future.
What is root cause analysis?
Root cause analysis is a structured method used to examine incidents, accidents, or system failures. It looks beyond the obvious and asks what underlying factors allowed the near-miss or incident to happen. This might highlight gaps such as lack of training, unclear procedures, poor communication, or equipment faults. The ultimate goal is not to assign blame but to identify and correct systemic weaknesses.
In health and safety management, a root cause analysis forms part of a proactive approach to risk reduction. It encourages continuous improvement and supports an organisation’s legal duty to protect workers from harm under the Health and Safety at Work etc. Act 1974.
Why is it important to find the root cause?
When organisations fail to identify the true cause of an incident, they risk repeating the same mistakes. Correcting only the immediate issue (for example, replacing a broken piece of equipment) may not address underlying organisational or behavioural factors.
A thorough root cause investigation allows employers to:
- Prevent recurrence by addressing systemic issues
- Improve safety culture through learning and transparency
- Strengthen compliance with legal duties and internal policies
- Demonstrate due diligence during inspections or enforcement actions
James Reason’s ‘Swiss Cheese Model’ illustrates how accidents occur when weaknesses in multiple safety barriers align, allowing an incident to pass through all defences. Root cause analysis helps identify why those gaps exist so they can be closed. Similar ideas include the domino theory, where one failure triggers another, and the iceberg model, which shows that visible incidents often stem from hidden underlying issues.
Does the law require root cause analysis to be undertaken after an incident?
While UK health and safety legislation does not explicitly require a “root cause analysis", it effectively expects employers to take an equivalent level of investigative action. Under the Management of Health and Safety at Work Regulations 1999, employers must assess risks and implement control measures. When an incident occurs, it is necessary to review those controls to ensure they remain effective.
Additionally, under RIDDOR (Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013), certain incidents must be reported to the Health and Safety Executive (HSE). The HSE’s guidance emphasises that thorough investigations are essential for preventing future accidents, and a root cause review is an accepted method for meeting this expectation.
In practice, failing to investigate properly can be seen as neglecting the duty to manage risks, which could lead to enforcement action or prosecution following serious incidents.
What techniques can be used to undertake a root cause analysis?
There are several structured techniques used to perform a root cause analysis. Two of the most common are the "5 Whys" method (developed by Sakichi Toyoda) and the "Fishbone Diagram" method (developed by Kaoru Ishikawa).
The 5 Whys approach involves repeatedly asking “why” after identifying each cause until the fundamental issue is revealed. For example:
- Why did the worker slip? – Because the floor was wet.
- Why was the floor wet? – Because of a leaking pipe.
- Why was the pipe leaking? – Because maintenance was delayed.
- Why was maintenance delayed? – Because inspection schedules weren’t followed.
- Why weren’t schedules followed? – Because staff were not trained on the maintenance system.
By the fifth “why?”, the true root cause (inadequate training) becomes clear. Depending on the complexity of the organisation and the severity of the incident, asking “why?” more than 5 times may be appropriate. However, 5 is a good rule of thumb.
The Fishbone Diagram is a visual method that helps teams categorise potential causes under key headings such as People, Processes, Equipment, Environment, and Management. By mapping these factors, investigators can identify patterns or connections that might otherwise be overlooked.
How can iCOR support organisations in undertaking a root cause analysis?
Conducting a thorough root cause analysis requires access to accurate and organised information. iCOR provides a smarter way to manage health, safety, and environmental compliance data. By centralising documents such as risk assessments, training records, inspection results, and incident reports, the platform makes it easier to find evidence when investigating why an event occurred.
With all compliance data stored in one secure, traceable system, organisations can quickly retrieve relevant information to support their root cause analysis.
Book a demo here to learn how iCOR can help you ensure that your investigations are evidence-based, effective, and efficient.