FMEA/FMECA occurrence

Assesses the likelihood of occurrence of potential misuse modes and their effect on safety before and after corrective actions. See also Failure Mode and Effects Analysis (FMEA/FMECA). 

Since in FMEA/FMECA corrective action and risk ranking are done on the basis of RPN, which is a product of severity, occurrence, and detection, it is possible that risk with less severity may get more priority (through RPN) than risk with more severity. 

RPN This is expressed in FMEA/FMECA in terms of product of severity, occurrence, and detection ranking in the scale of 0—1000. 

Detection is related to causes of failure and controls, as shown in Fig. IV/2.1-1. Thus there are two ways to look at it preventive and detection control. In prevention, with the help of existing controls, failure modes are prevented, whereas the other way detects the failure and takes corrective action before it reaches the customer (see Fig. IV/2.2.1-1). FMEA/FMECA identifies the method by which occurrence of failures/failure modes is detected by the operating personnel. Audio... 

When criticality analysis is also done it is referred to as FMECA. In fact, prioritization is done mainly based on criticality analysis so that the most critical issue is addressed first. FMEA reduction may be in terms of reducing severity or lowering the occurrence, or both. When the root cause is addressed, then it will be almost impossible to occur. So, in a nutshell, FMEA could be used as a guiding tool to the complete set of actions in product development process so that risks are either avoided or mitigated in the systems, subsystems, or components (to an acceptable limit). 

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