Root cause causal factor identification

Causal factor identification tools are relatively easy to learn and easy to apply to simple incidents. For more complex incidents with complicated timelines, one or more causal factors can be overlooked, ultimately leading to missed root causes. Another disadvantage is that an inexperienced investigator could potentially assume that suppositions are causal factors, when in reality the supposed event or condition did not occur. 

Error analysis techniques can be used in accident analysis to identify the events and contributory factors that led to an accident, to represent this information in a clear and simple manner and to suggest suitable error reduction strategies. This is achieved in practice by identification of the causal event sequence that led to the accident and the analysis of this sequence to identify the root causes of the system malfunction. A discussion of accident analysis techniques is included in Chapter 6. 

Training Agenda Data collection Causal factor determination Root cause identification Writing... 

In general, the companies surveyed use one of two main methodologies to determine root causes. The first involves timeline construction followed by logic tree development. The second involves timeline construction, identification of causal factors, followed by the use of predefined trees or checklists. These two approaches are discussed in detail in Chapter 9. 

The identification of causal factors points us to the key areas that need to he examined further for why that factor existed. It acts as a filter to limit the number of areas that are subjected to further analysis to determine root causes. This critical activity must be performed diligently and systematically to identify every causal factor applicable to the specific incident. If a causal factor is missed, one or more root causes will likely be omitted as well, which could lead to similar incidents in the future. 

The article (Rooney Vanden Heuvel, 2004) uses the term Root Cause Map as an equivalent to the term predefined tree, when the fourth step of the method B of root cause analysis is discussed. According to the article, root cause identification involves the use of a decision diagram called the Root Cause Map to identify the underlying reason or reasons for each causal factor . Fig. 3 shows a small part of a specific Root Cause Map that is reproduced from (CCPS, 2003). It is a subtree of larger decision tree. Displayed part helps the investigator identify detail causes in the SMS, namely, in a fraction of its component (iii) operation control. 

Root cause identification connects the specific chains of underlying causes from causal factor chart to generic chains of underlying causes from the Root Cause Map. Final nodes of the generic chains represent the most accurate causes in the safety management system. 

---