Root Cause Failure Analysis

PURPOSE OF THE ANALYSIS

The purpose of RCFA is to resolve problems that affect plant performance. It should not be an attempt to& blame for the incident. This must be clearly understood by the investigating team and those involved in the process. Understanding that the investigation is not an attempt to fix blame is important for two reasons. First, the investigating team must understand that the real benefit of this analytical methodology is plant improvement. Second, those involved in the incident generally will adopt a self-preservation attitude and assume that the investigation is intended to find and punish the person or persons responsible for the incident. Therefore, it is important for the investigators to allay this fear and replace it with the positive team effort required to resolve the problem.

EFFECTIVE USE OF THE ANALYSIS

Effective use of RCFA requires discipline and consistency. Each investigation must be thorough and each of the steps defined in this manual must be followed. Perhaps the most difficult part of the analysis is separating fact from fiction. Human nature dictates that everyone involved in an event or incident that requires a RCFA is conditioned by his or her experience. The natural tendency of those involved is to filter input data based on this conditioning. This includes the investigator. However, often such preconceived ideas and perceptions destroy the effectiveness of RCFA. It is important for the investigator or investigating team to put aside its perceptions, base the analysis on pure fact, and not assume anything. Any assumptions that enter the analysis process through interviews and other data-gathering processes should be clearly stated. Assumptions that cannot be confirmed or proven must be discarded.

PERSONNEL REQUIREMENTS

The personnel required to properly evaluate an event using RCFA can be quite substantial. Therefore, this analysis should be limited to cases that truly justify the expenditure. Many of the costs of performing an investigation and acting on its recommendations are hidden but nonetheless are real. Even a simple analysis requires an investigator assigned to the project until it is resolved. In addition, the analysis requires the involvement of all plant personnel directly or indirectly involved in the incident. The investigator generally must conduct numerous interviews. In addition, many documents must be gathered and reviewed to extract the relevant information. In more complex investigations, a team of investigators is needed. As the scope and complexity increase, so do the costs. As a result of the extensive personnel requirements, general use of this technique should be avoided. Its use should be limited to those incidents or events that have a measurable negative impact on plant performance, personnel safety, or regulatory compliance.

WHEN TO USE THE METHOD

The use of RCFA should be carefully scrutinized before undertaking a full investigation because of the high cost associated with performing such an in-depth analysis. The method involves performing an initial investigation to classify and define the problem. Once this is completed, a full analysis should be considered only if the event can be fully classified and defined, and it appears that a cost-effective solution can be found. Analysis generally is not performed on problems that are found to be random, nonrecurring events. Problems that often justify the use of the method include equipment, machinery, or systems failures; operating performance deviations; economic performance issues; safety; and regulatory compliance issues.