FMECA failure mode, effects, and criticality

FMECA - Failure Modes, Effects and Criticality Analysis. 

HSE assessments have a long tradition within the oil-and gas industry. These assessments use a wide range of methodologies, from the strict quantitative methods such as QRA (Quantitative Risk Analysis) and FMECA (Failure Mode Effect and Criticality Analysis) to the more qualitative methods such as HAZOP (HAZard OPerability analysis). Most methods combine qualitative and quantitative data and approaches. For example, an FMECA basically uses generic failure data, expert judgments are likewise important. 

FMECA Failure mode, effects, and criticality analysis... 

Technology assessment (Westrum 1991) aims considering the potential consequences of new technological system. Several methods and tools exist to support such assessment. In the context of safety and security, brainstorming, expert groups and traditional risk assessment methods such as FMECA (Failure Mode, Effects and Criticality Analysis) are often used with the purpose of identifying potential risks related to the adoption of a new technology. 

In this section, the qualitative analysis aimed at identifying the hazards and failure mechanisms associated to the operation of a system is exemplified by way of a very common method known as failure mode and effects analysis (FMEA). Actually in practice, a FMECA (failure mode, effects, and criticality analysis) is typically performed to arrive at also assigning a criticality class to each failure mode, for example, according to the following ranking ... 

Critical examination of plant operations also described as hazard and operability study (HAZOP) and described as FMECA, (failure mode, effect and criticality analysis)... 

We previously encountered failure modes and effects (FMEA) and failure modes effects and criticality analysis (FMECA) as qualitative methods for accident analysis. These tabular methods for reliability analysis may be made quantitative by associating failure rates with the parts in a systems model to estimate the system reliability. FMEA/FMECA may be applied in design or operational phases (ANSI/IEEE Std 352-1975, MIL-STD-1543 and MIL-STD-1629A). Typical headings in the F.Mld. A identify the system and component under analysis, failure modes, the ef fect i>f failure, an estimale of how critical apart is, the estimated probability of the failure, mitigaturs and IHissihiy die support systems. The style and contents of a FMEA are flexible and depend upon the. ilitcLiives of the analyst. 

Perhaps the key to detcrnuiiiiig die consequences of an accident is die study of accident mininiization/prcvendon. This topic receives extensive treatment in Section 17.2. The estimation (not calculadon) of consequences is treated in Section 17.3, which is followed by evacuation procedures (Section 17.4). The next section e.xaniiiies failure modes, effects and critical analysis (FMECA). The cluipter concludes with vulnerability analysis (Section 17.6) and event tree analysis (Section 17.7). 

The first step in FMECA is to determine a level of resolution. If a system-level liazard is to be addressed, equipment in die system must be studied for a plant-level hazard, individual systems within die plant must be examined. Once the level of resolution luis been determined, a format must be developed-one to be used consistendy tlu oughout die study. A minimal format should include each item, its description, failure modes, effects, and criticality ranking. 

Failure Modes, Effects and Criticality Evaluation (FMECA) is a systematic qualitative metliod by which equipment and system failures and tlie resulting effects of these failures are detennined. FMECA studies possible events, but not tlie reasons for tlieir occurrences. 

Failure mode, effects, and criticality analysis (FMECA) This method tabulates a list of equipment in the process along with all the possible failure modes for each item. The effect of a particular failure is considered with respect to the process. 

From those techniques given in Table 1 my personal preference is for failure mode, effects, and criticality analysis (FMECA). This technique can be applied to both equipment and facilities and can be used to methodically break down the analysis of a complex process into a series of manageable steps. It is a powerful tool for summarizing the important modes of failure, the factors that may cause these failures, and their likely effects. It also incorporates the degree of severity of the consequences, their respective probabilities of occurrence, and their detectability. It must be stressed, however, that the outcome of the risk assessment process should be independent of the tool used and must be able to address all of the risks associated with the instrument that is being assessed. 

Failure mode effects and criticality analysis (FMECA) Empirical risk management (ERA)... 

The principles utilized in these expert systems are general purpose and based on failure modes, effects and critically analysis, FMECA, a sub-process of reliability centred maintenance, RCM, and statistical process control, SPC. The analysis paradigm includes ... 

Figure 13.8. a) Comparison of safety risk assessment and risk management and b) general principles of FMECA approaches (failure mode, effects and criticality analysis) applied to materials in contact with food... 

One hazards analysis technique used to analyze equipment items is FMEA. The method examines the ways in which an equipment item can fail (its failure modes) and examinees the effects or consequences of such failures. If the criticality of each failure is to be considered, then the method becomes a Failure Modes, Effects and Criticality (FMECA) Analysis. The consequences can be to do with safety, reliability, or environmental performance. 

Borgovini, Pemberton, R., Ross, S., 1993. Failure Mode, Effects and Criticality Analysis (FMECA). Reliability Analysis Center. 

BS5760, 1991. Reliability of Systems, Equipment and Components Part 5 Guide to Failure Modes, Effects and Criticality Analysis (FMEA and FMECA). British Standards Institute. 

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