Failure Modes Effects Analysis objectives

Two distinctly different, yet complementary, perspectives of hazards for the HCF and associated radioactive material storage locations are obtained for the overall hazard analysis of Chapter 3 by using both PHA and failure mode effects analysis (FMEA) techniques. FMEA is a complementary type of evaluation that utilizes a system failure-based form of analysis. Unlike PHA, the first objective of FMEA is to subdivide the facility Into several different (and, to the maximum extent possible, independent) system elements. Failure modes of each system element are then postulated and a structured examination of the consequences of each failure mode follows. However, similar to PHA, FMEA documents preventive and mitigative features (failure mechanisms and compensation) and anticipated accident consequences (failure effects). Appendix 3D contains the FMEA for the HCF. 

Failure Mode and Effects Analysis. The system design activity usually emphasizes the attainment of performance objectives in a timely and cost-efficient fashion. The failure mode and effects analysis (FMEA) procedure considers the system from a failure point of view to determine how the product might fail. The terms design failure mode and effects analysis (DFMEA) and failure mode effects and criticaUty analysis (EMECA) also are used. This EMEA technique is used to identify and eliminate potential failure modes early in the design cycle, and its success is well documented (3,4). 

RCM sometimes referred to as Preventive Maintenance Optimisation (PMO) has become popular in recent years within several industries. The concept has been discussed and elalx>rated by several authors (Worledge (1993), Rausand (1998), Sherwin (1999)). RCM is a procedure for determining maintenance strategies based on reliability techniques and encompasses well-known analysis methods such as Failure Mode, Effects and Criticality Analysis (FMECA). RCM procedure takes into account the prime objectives of a maintenance programme ... 

Failure Modes and Effects Analysis. Failure modes and effects analysis (FMEA) is applied only to equipment. It is used to determine how equipment could fail, the effect of the failure, and the likelihood of failure. There are three steps in an FMEA (4) (7) define the purpose, objectives, and scope. Large processes are broken down into smaller systems such as feed or cooling. At first, the failures are only considered to affect the system. In a more general study, the effects on a plant-wide basis can be considered. (2) Define the problem and boundary conditions. This includes identifying the system to be studied, establishing the physical boundaries, and labeling the equipment with a unique identifier for use in the FMEA procedure. (3)... 

Failure Modes and Effects Analysis (FMEA) This will document a review of the effects of faiiure of the component parts of the system. This review is mainiy aimed at assessing the system hardware, interfaces and environment. This review shouid be performed on two lev-eis The first ievei reviews the possibie failure modes of each individual system and the second level assesses the possible failure modes of the combined system. The overall objective of the FMEA is to identify the potentiai weak points and then to identify how these weak points may be designed out of the system. This may be achieved by instaiiing redundancy, redesigning parts of the system, recommending procedural controls and so on. The results of this review should be documented as a FMEA Review Report or as part of a DQ Report. 

A Failure Modes and Effects Analysis (FMEA) is a systematic technique that is designed to identify problems. It is a "bottom up" method that starts with a detailed list of all components within the system. The overall objective is to identify design flaws, imexpected results, when components of the system fail. A whole system can be analyzed one component at a time. 

Often authors analyze in detail the separate objects of infrastructure. They used the criticality assessment methods, such as Failure Modes their Effects and Criticality Analysis [Hammoum et al,... 

The SESAR safety assessment approach typically uses static risk modelling techniques safety criteria and objectives are identified based on accident incident models and further safety requirements are derived using Fault Trees, Failures Modes and Effects Analysis or similar techniques. This section presents criteria to identify specific cases where DRM application is required. 

There are a variety of tools and techniques available for assessing safety, which can broadly be classified into two categories. Top-down analysis starts by identifying the accidents or failure conditions to be investigated, and then proceeds to derive the combination of failures and/or events which can produce them. Bottom-up analysis starts with hardware failure modes which can occur and analyses the effects of these on the system and aircraft in order to determine the hazardous conditions which can occur. The objectives of these techniques fall into three broad categories ... 

A preliminary system safety assessment (PSSA) is essential in order to determine (and agree) the depth of assessment needed, the criteria utilised and the manner in which the safety objectives are to be accomplished. The PSSA concentrates on the functions and vulnerabiUties of the system instead of the detailed analysis, and can thus be conducted prior to the definition of the system s architecture. The PSSA remains a live document until the final SSA can be issued. By the preliminary design review (PDR), the PSSA should include functional failure consequences to the aircraft and its occupants consequences of other possible malfunctions of a system (e.g. overheating) and their effects on surrounding systems consequences to the system of failure in other systems or parts of the aircraft, identification of any possible common-mode failures or cascade failures which my need detailed investigation the identification of possible vulnerabilities to flight crew or maintenance error. 

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