Root cause analysis system evaluation

Root cause analysis systems, intended to provide in-depth evaluations of major incidents... 

However, in the case of a root cause analysis system, a much more comprehensive evaluation of the structure of the accident is required. This is necessary to unravel the often complex chain of events and contributing causes that led to the accident occurring. A number of techniques are available to describe complex accidents. Some of these, such as STEP (Sequential Timed Event Plotting) involve the use of charting methods to track the ways in which process and human events combine to give rise to accidents. CCPS (1992d) describes many of these techniques. A case study involving a hydrocarbon leak is used to illustrate the STEP technique in Chapter 7 of this book. The STEP method and related techniques will be described in Section 6.8.3. 

In the case of root cause analysis systems, more comprehensive evaluations of PIFs will normally be carried out as part of a full-scale human factors audit. This could make use of the types of comprehensive PIF evaluation methods described in Chapter 2 (see Section 2.7.7 and Figure 2.12). 

For a major incident investigation using a comprehensive root cause analysis system, teams will be formed to acquire information relevant to determine the structure and analyze the causes in depth. In addition to evaluations of the immediate causes, imderlying causes are likely to be evaluated by investigations in areas such as safety and quality management. Both paper- and computer-based systems will be used to acquire and record information for subsequent detailed analyses. 

In addition to incident reporting systems, root cause analysis techniques can be used to evaluate the causes of serious incidents where resources are usually available for in-depth investigations. A practical example of root cause investigation methods is provided in Chapter 7. 

A corrective action is initiated to correct the cause of an identified nonconformity and to prevent it or similar problems from reoccurring. It may include initial and follow-up actions (e.g., conducted after root cause analysis). Current quality system models and the cGMP regulations emphasize corrective actions and require that actions be documented. Under current quality system models, preventive actions include actions taken in response to quality data to address the cause of potential nonconformities to prevent their occurrence. An effective CAPA system therefore includes both reactive and proactive components. The effectiveness of corrective and preventive actions should be evaluated using objective criteria when possible and the evaluation documented. 

Complexity introduces additional challenges when it comes to evaluating faults and live service incidents. A key element in undertaking a root cause analysis is to be able to faithfully reproduce deviant behaviour. Faults in complex systems are more likely to be intermittent, unpredictable, non-deterministic and seemingly random. In particular it can be challenging to predict combinations of failures which might impact the system as a whole. Without an accurate set of pre-conditions on which to base the analysis any attempts to fix the issue will be severely hampered. 

The value of root cause analysis is that conclusions are reached that may address a much broader range of issues than those immediately to do with the event being investigated. For example, the initial evaluation of the reverse flow problem in the standard example finds that the check valve failed. Further examination identifies a root cause that all check valves purchased from the manufacturer of that particular valve are unreliable and need to be replaced. This conclusion may, in turn, suggest weaknesses to do with the company s overall procurement system. 

As Pounds says, several of the behavioral tools he describes are not a part of the typical BBS process. Also, Pounds says that the concept that he puts forth can be extended to resolve a multitude of business initiatives. A list of the major captions in his program follows. It s different it s performance-oriented. No other BBS outline that has come to this author s attention is comparable, nor do others include such elements as root cause analysis, environmental impact analysis (reengineers performance systems), behavioral consequence impact analysis (evaluates job... 

Root cause analysis 5 There Is a system in place to evaluate the root cause of all accidents/ Incidents, even near misses... 

Root cause analysis is used when there are multiple problems with a number of causes of an accident. A root cause analysis is a sequence of events that shows, step by step, the events that took place in order for the accident to occur. Root cause analysis puts all the necessary and sufficient events and causal factors for an accident in a logical, chronological sequence. It analyzes the accident and evaluates evidence during an investigation. It is also used to help prevent similar accidents in the future and to validate the accuracy of preaccidental system analysis. It is used to help identify an accident s causal factors, which, once identified, can be fixed to eliminate future accidents of the same or of similar nature. 

Safety program elements. Analysis and evaluation of the safety system elements determine the effectiveness of the current safety policies, programs, plans, processes, and procedures. These represent the root causes that have allowed surface causes to develop and exist. Always evaluate systems in your comprehensive baseline survey. 

The criticality is then multiplied by the detection value to give a Risk Priority Number (RPN). The numerical value for detection is inverse to the detection rate (a detection rate of 100% has a numerical value of zero, while a detection rate of 0% has the highest numerical value). The failure modes are then ranked basked on RPN. Additional information can then be evaluated based on whether root causes are to be evaluated, what mitigating efforts should be made, etc. While EMEA primarily utilizes qualitative assessments, it provides a robust means for quantitative analysis of complex systems. 

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