Incident investigation causal factor determination

Post incident—through investigation of hazards-related incidents for causal factor determination... 

Causal factor determination varied greatly as to quality In some of companies, it is poorly done. How poorly It was necessaiy to report to some of the safety directors who provided investigation forms that on a scale of 10, their incident investigation systems scored a 2. (See Chapter 11, Incident Investigation Studies of Quality.)... 

Of the 15 variations of incident investigation reports received, six promote an overly simplistic and inappropriate approach to causal factor determination. They reflect this instmction, although somewhat ancient, given in a publication of the American National Standards Institute, the Method of Recording Basic Facts Relating to the Nature and Occurrence of Work Injuries—Z16.2. 

It is a too common practice that persoimel with safety in their titles place their signatures, indicating acceptance and approval, on incident investigation reports that are far from adequate, particularly concerning causal factor determination. 

In some entities, it is required that an incident investigation team be selected and gathered if the results of the incident were serious or could have been serious under other circumstances. Reports prepared by investigation teams (12 of them were received) were a pleasure to read. Every one reflected an understanding of multiple causation and pursued several routes in causal factors determination and in selecting corrective actions. 

Whittingham asserts that in some organizations, a blame culture exists whereby the focus in the investigation of incidents resulting in severe consequences is on individual human error, and the corrective action taken occurs at that level, rather than within the system that may have enabled the human error. He stresses that placing responsibility for the incident on what an individual did or did not do results in overly simplistic causal factor determination. 

Although it is suggested that, in the study proposed, the reality of the design and engineering, operational systems, and cultural causal factors be identified and analyzed, safety professionals should not be surprised if the incident investigation reports are inadequate for in-depth causal factor determination. Mention was made previously of my studies of over 1200 incident investigation reports and that I found, in many instances, that causal factor determination was dismal. 

In Chapter 3, Serious Injury Prevention, I commented on studies made of over 1200 incident investigation reports to assess the effectiveness of the incident investigation systems in place. I said that on a scale of 10, with 10 being best, some companies scored a 2, that causal factor determination was poor, and that opportunities to re-adjust the focus of preventive efforts to the benefit of workers and employers were lost. Observations were not made in that chapter on a rationale that may explain why incident investigations are often superficial. 

The team reviews causal factors against investigative checkiists to determine why that factor existed at the time of the incident. A combined what if/pheckfist approach may be used. 

Once the evidence has heen collected and a timeline or sequence diagram developed, the next phase of the investigation involves identifying the causal factors. These causal factors are the negative occurrences and actions that made a major contrihution to the incident. Causal factors involve human errors and equipment failures that led to the incident, hut can also he undesirable conditions, failed harriers (layers of protection, such as process controls or operating procedures), and energy flows. Causal factors point to the key areas that need to he examined to determine what caused that factor to exist. 

Checklist analysis tools can be a user-friendly means to assist investigation teams as they conduct root cause analysis.h) Each causal factor is reviewed against the checklist to determine why that factor existed at the time of the incident. The Systematic Cause Analysis Technique (SCAT)(9> is an example of a proprietary checklist tool. 

Some investigators review each of the causal factors to determine the immediate causes (unsafe acts or rmsafe conditions) of the incident, as an... 

The existence of an indeterminate number of root causes may help explain some of the frustration that is occasionally expressed with standardized incident analysis procedures and software. In spite of their structured approach, these systems are fundamentally subjective. For example, one technique helps the investigation team list many of the possible causes that led to an event. Some of these causes are then identified as causal factors which are then developed into root causes. Yet the determination as to which causes are causal factors will necessarily depend on the... 

The incident investigation report recorded the causal factor as employee failed to follow the established lockout/tagout procedure. Later, it was determined that the distance to the power shut off was 216 feet. In that work situation, where fatigue had become a factor, it was judged that the design of the lockouf/tagout system whereby the power shut off was not immediately accessible encouraged the employee s... 

Setting the above knowledge and proposals together leads to integrated incident investigation procedure which is stUl based on the timeline development, causal factor identification and causal factor chart development, but which allows the determination of different Incident Cause Level for each of multiple causes. If the Incident Cause Level of specific cause is outside the internal safety management, the apph-cation of non-hnear analysis method is recommended. 

Post incident, through investigation of hazards-related incidents and exposures to determine and eliminate or control their causal factors... 

Postincident Stage where investigations are made of incidents and exposures to determine the causal factors that will lead to appropriate interventions and acceptable risk levels. 

The incident investigation report recorded the causal factor as employee failed to follow the established lockout/tagout procedure. Later, it was determined that the distance to the power shut off was... 

---