Accident Causation Model

Below is a simplified model of accident causation. Simplified but including the main phases or chain of events that lead to accidents - from the Management System on the left to the Consequences on the right. Simplified but perfect for communication purposes!

While the model shows the accident causation sequence, it can also be used for accident analysis. In that case it must be read from right to left.   

The model was originally developed by Heinrich/Lateiner during the thirties of last century. At that time "Management System" was labelled "Ancestry - Social Environment" while "Basic Causes" was called "Fault of Person". Obviously not something you could manage very well in an industrial environment.

Frank E. Bird Jr. renamed the domino's and made clear the relation between the undesired event and its consequences and the Management System via Direct and Basic or "root" Causes. It was Mr. Bird who showed the way by making the accident sequence a manageable and controllable matter.

The model above is a simplified reflection of the real life situation but powerful for communication purpose: it relates the management system to the event and the results thereof, either good or bad, depending on the quality of the system.

I have tried to make the model "better" so it may appeal more to professional safety people and have added one domino at the end of the sequence. I ended up with the following model:  

The text on the domino's is a little different from the 2-D model but, without any further explanation, I think you get the idea about the complexity that accident causation models can have. I included the "barrier concept" between the event and the initial loss. I also realized that the final loss depends on the actions to reduce loss and added the emergency services as well as Post Event Planning (PEP) intended to get the operation back to normal as soon as possible. Please note that I only have one management system at the far left end. Obviously there could be more than one  - not preferable but often practice following various certification processes.

There are more causation models ranging from simple to complex. If too simple, you can do little with it, if too complex it may be difficult to explain. What is important is that the model has communication value - particular to explain the model to management and employees. Also important is that the model has broad international acceptance. The 5-domino model has both - the history goes back to the original Heinrich model about 80 years ago and the Bird model from the sixties of last century.

In 1990 I did a study for the Dutch Ministry of Social Affairs covering about 15 - 20 different models to include: Heinrich, Bird, Mort, Swain, De Reamer, Adams, Kjellen, Hudson/Reason and others but concluded that the 5-domino model (Heinrich/Bird) was most suitable. The Bird model relating the management system to the unwanted event is the one that provides opportunities for managing safety (or other business aspects).