Immediate, Underlying and Root Causes of Health and Safety Incidents

Health and safety incidents can have severe consequences for individuals and organisations. To prevent these incidents from occurring, organisations need to understand their causes. This article will examine the three levels of causation in health and safety incidents: immediate, underlying, and root causes.

Immediate Causes 

Immediate causes are the most visible and direct reasons for an incident. They are the events or actions that result in an injury or illness. For example, a worker may fall off a ladder, a machine may malfunction, or a chemical spill may occur. The immediate cause is often the easiest to identify, as the event directly led to the incident.

However, it is essential to note that immediate causes are often symptoms of more significant underlying issues. Therefore, identifying and addressing the underlying causes can help prevent future incidents.

Underlying Causes 

Underlying causes are the systemic and organisational factors that contribute to incidents. They are the conditions or events that create the opportunity for the immediate cause to occur. For example, inadequate training, poorly designed equipment, or insufficient safety policies and procedures can all be underlying causes.

Identifying and addressing underlying causes requires a more in-depth investigation than identifying immediate causes. For example, it may involve reviewing safety procedures, examining equipment maintenance records, and interviewing employees. By addressing underlying causes, organisations can significantly improve their safety culture and prevent future incidents.

Root Causes

Root causes are the fundamental reasons why underlying causes exist. They are the core issues that create a work environment where safety incidents are more likely to occur. For example, inadequate resources, communication, and a lack of safety leadership can all be the root causes.

Identifying and addressing root causes requires a comprehensive investigation into the organisation’s culture and systems. It may involve reviewing leadership practices, assessing the effectiveness of communication channels, and evaluating resource allocation. By addressing root causes, organisations can make fundamental changes to their safety culture and prevent incidents from occurring in the future.

The Domino Effect

Domino theories of accident causation suggest that accidents result from a chain of sequential events, like a line of dominoes falling over. When one of the dominoes falls, it triggers the next one and the next, eventually resulting in an accident, injury, or other loss.

Accident prevention strategies involve removing one of the dominoes from the chain to prevent the sequence from progressing to the accident.


A good accident investigation will identify the sequence of events and conditions that led up to the adverse event and identify the immediate (direct), underlying and root causes.

Accidents typically arise because of a combination of causes, so rather than a linear row of dominoes, it is better represented as a tree with multiple rows of dominoes coming together to cause the accident.

Health and safety incidents can have severe consequences, but they are often preventable. 

By understanding the three levels of causation – immediate, underlying, and root causes – organisations can identify areas for improvement and make changes that improve safety culture and prevent incidents from occurring. It is essential to not only address the immediate causes of incidents but also to delve deeper and address the underlying and root causes.