Incident investigation causation models

If several safety professionals investigate a given hazards-related incident, they should identify the same causal factors, with minimum variation. That is unlikely if the thought processes they use have greatly different foundations. At least 25 causation models have been published. Since many of them conflict, all of them cannot be valid. A review of some of them is followed by a discussion of principles that should be contained in a causation model. 

I conducted workshops on selected incident reports they had sent me. To help the attendees explore the reality of accident causation, they were given copies of the exhibit A Systemic Causation Model for Hazards-Related Incidents shown in Chapter 10. It works as a reference base. The point to be made was this The employees in that entity could do a good job of investigation if management so required. 

Dr. Chapanis offered four axioms that deserve thought both in determining what incident causation model is to apply and in drafting an incident investigation report form. 

MORT Safety Assurance Systems by WilMam G. Johnson This text serves well both for incident causation model building and for incident investigation. The accident investigation chapter states that while accident investigation has always been a major element in safety, pre-accident hazard analysis is preferable (p. 347). 

When designing an incident investigation and analysis process, a determination must be made concerning the causation model on which the process is to be based. What the designer of the process believes are the facts about incident causation has to be established before an instmctional guide can be written or a training program developed. Consider these extremes. 

This section will provide an overview of an incident causation model that we believe will help you understand the investigation concepts for establishing the root cause of an incident. 

It is evident and convincing that several observers recognize the impact that management decisions have on what become causal factors for hazards-related incidents in the sociotechnical work environment— in the system in which work is done. Similarly, this author s review of over 1700 incident investigation reports results in the conclusion that decisions made at a board of directors and at senior management level must be given prominence in a causation model. Figure 13.1 depicts such a causation model. Comments in support of the model follow. 

Investigators can systematically analyze data from past incidents to identify lessons learned and develop incident stereotypes. This makes it possible to develop a model displaying the anatomy of a process-related incident using a conceptual framework. Figure 3-1 provides a tool to help us understand incident causation. 

Theoretical incident concepts and associated models have evolved from investigations into the how and why of case histories. Resulting insights have made it possible to better explain and understand incident causation. There are many other incident causation theories besides the ones presented in this chapter, such as the Process Theory. (See the additional references for this chapter.) Key theories on incident causation discussed in this overview are ... 

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