Accident Causation Models

Accident Causation Models

Many models of accident causation have been proposed, ranging from Heinrich's domino theory to the sophisticated Management Oversight and Risk Tree (MORT).

The simple model shown in Figure 1 attempts to illustrate that the causes of any accident can be grouped into five categories - task, material, environment, personnel, and management. When this model is used, possible causes in each category should be investigated. Each category is examined more closely below. Remember that these are sample questions only: no attempt has been made to develop a comprehensive checklist.

Figure 1: Accident Causation

Task

Here the actual work procedure being used at the time of the accident is explored. Members of the accident investigation team will look for answers to questions such as:

· Was a safe work procedure used?

· Had conditions changed to make the normal procedure unsafe?

· Were the appropriate tools and materials available?

· Were they used?

· Were safety devices working properly?

· Was lockout used when necessary?

For most of these questions, an important follow-up question is "If not, why not?"

4. Please, analyzethe basic investigation stages.

The accident investigation process involves the following steps:

· Report the accident occurrence to a designated person within the organization

· Provide first aid and medical care to injured person(s) and prevent further injuries or damage

· Investigate the accident

· Identify the causes

· Report the findings

· Develop a plan for corrective action

· Implement the plan

· Evaluate the effectiveness of the corrective action

· Make changes for continuous improvement

As little time as possible should be lost between the moment of an accident or near miss and the beginning of the investigation. In this way, one is most likely to be able to observe the conditions as they were at the time, prevent disturbance of evidence, and identify witnesses. The tools that members of the investigating team may need (pencil, paper, camera, film, camera flash, tape measure, etc.) should be immediately available so that no time is wasted.

5. Please, give the estimation of algorithm of investigation.