Root Cause Analysis Methods

The most common root cause analysis methods are as follows  

Events and causal factor analysis identifies the time sequence of a series of tasks and actions and the surrounding conditions leading to an occurrence. 

Change analysis is used when the problem is obscure. It is a systematic process that is generally used for a single occurrence and focuses on elements that have changed. 

Barrier analysis is a systematic process that can be used to identify physical, administrative, and procedural barriers or controls that should have prevented the occurrence. 

Energy sources Hazardous materials Unsafe acts Unsafe conditions Inadequate policy and/or decisions Environment and/or personal factors 

Management Oversight and Risk Tree (MORT) Analysis is used to identify inadequacies in barriers and controls, specific barrier and support functions, and management functions. It identifies specific factors relating to an occurrence and identifies the management factors that permitted these 

Human Performance Evaluation identifies feetors that influence task performance. The focus of this analysis method is on operability, work environment, and management factors. Man-machine interfece studies 

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In the second case study, variation tree analysis and the events and causal factors chart/root cause analysis method are applied to an incident in a resin plant. This case study illustrates the application of retrospective analysis methods to identify the imderlying causes of an incident and to prescribe remedial actions. This approach is one of the recommended strategies in the overall error management framework described in Chapter 8. 

The term cause within this section refers to inadequate process safety management practices. The causal information presented is not intended to be considered as root causes no consistent root cause analysis methods were identified within the data. 

The use of checklists to supplement another root cause analysis method can be a very powerful technique, for example, human factors checklist(s) may be used in conjunction with logic trees. The checklist may be used as a guide during development of a logic tree, or as a check after the tree has been developed. The checklist essentially acts as a memory jogger to direct the investigation team. This is especially helpful if the team lacks previous experience in the subject matter. 

The assessment phase includes analyzing the data to identify the causal factors, summarizing the findings, and categorizing the findings according to cause. Any root cause analysis method may be used that includes the following steps ... 

FIGURE 8.1 Summary of root cause analysis methods flowchart. (Source Courtesy of the United States Department of Energy.)... 

Each accident/incident should be methodically analyzed using an accident investigation/root cause analysis approach. Because many root cause analysis methods exist, it will be the investigator s responsibility to select the appropriate analysis approach (e.g., barrier analysis). Use of proper accident/incident investigation methods and tracking will lead to intervention, which will successfully prevent further occurrence of these occupational accidents and incidents. 

Root cause analysis methods Techniques—Interviewing witnesses... 

In Spain, the utilities must have personnel trained in the use of a widely accepted root cause analysis method and normally this is the Human Performance Enhancement System (HPES). Such analyses are expected for any significant event occurring at the plants. Some plants cany out detailed root cause analyses of most events. 

Root cause analysis methods are used only for patient safety, not all safety events. The facility believes a one-size-fits-all safety program approach will work. 

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