One of the earliest formal theories of accident causation was developed by Heinrich in 1931. He analysed 75,000 accident reports from companies insured with Travelers Insurance Company and developed the “domino” theory of accident causation (cited in Bamber, 2003).

Heinrich concluded that 88 per cent of all accidents were caused by unsafe acts of people, 10 per cent by unsafe conditions and that 2 per cent were caused by acts of God (e.g. “natural” accidents).

Based on his findings, Heinrich identified five factors in the accident sequence. These are social environment and ancestry, fault of the person (carelessness), unsafe act and/or mechanical/physical conditions, the accident, and finally, the injury itself.

Social environment and ancestry included the social learning of custom and practice in the workplace, as might be evidenced in an apprentice learning from his master. The “carelessness” factor included negative personal characteristics of the individual; however they might have been acquired.

Unsafe acts or physical conditions were the errors or technical failures, which led directly to the accident which resulted in the injury. In essence, removal of the unsafe act or condition would prevent the accident.

Heinrich’s theory of accident causation is a simple linear sequence of events. It explains “what happened”, but it doesn’t provide much information on why the accident occurred.

In addition, the model essentially lays accidents firmly at the door of the unsafe act or mechanical condition – without examining any underlying or contributory factors.

This early theory has been superseded by more sophisticated theories of accident causation, but Heinrich’s terms “unsafe act” and “unsafe condition” are still very much in use.

A more complex domino theory suggests that adverse events have immediate causes, underlying causes and root causes. The immediate causes are the actual agents of injury or ill health – the blade, the substance or the fumes.

The underlying causes of a workplace accident are the unsafe acts and unsafe conditions which gave rise to the immediate cause, such as where a guard is removed, the window closed or the ventilation switched off.

The root causes of the adverse event are the failures from which all other failures stem. For example, a failure to adequately assess risk, incomplete analysis of training needs, lack of monitoring and control.

Elimination of underlying and root causes potentially prevents a whole series of adverse events, while addressing immediate causes would only prevent recurrence of the specific adverse event which arose.

This model is more sophisticated than that proposed by Heinrich, but many safety and accident theorists would nevertheless dispute the existence of a “root cause” as being too simplistic.

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Unknown said...

Sometimes accidents at workplace occur due to the negligence the employer or third party in such cases the worker who is injured should make a compensation claim and has to prove that the injury, illness or disease was caused as a consequence of the carelessness of another party. If you consult an experienced personal injury solicitor then assist you with the right process how to make a personal injury accident claims so that you should get the compensation.

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