Shivkumar Samant

The "Sigma Level Metric" is not the end in itself. That can't be the goal because: (i) There will always be room for improvement. (ii) Every operating environment is continually undergoing change. Hence, even a successful method needs to be adapted to changed circumstances; and this will necessitate an approach to look for opportunities to cut the NVA's all the time. (iii) A dimension overlooked until now may come to light - and this is possible only if the process of questioning the obvious is instilled; e.g. why are we doing this? Unless "Six Sigma" is accepted as a philosophy, such process review will not happen; and people may keep measuring and reporting the same kind of metric without looking into whether the metric is really relevant in changed business scenario.

FMECA includes performing Criticality analysis after standard FMEA. FMEA is typically a table-top exercise where possible causes for failure are identified. Estimates of rankings are assigned to severity, occurrence and detection – before and after the corrective action plan. FMECA goes one step forward – to determine criticality of the effect, and therefore a preventive action plan. FMECA can be performed at any stage of system design: (i) during the early development stages; (ii) updates throughout the development; (iii) near the end of the design process. FMECA facilitates determination of how a system can be modified to improve overall reliability and to avoid failures. Once FMECA has identified possible failures, we can explore ways to prevent the failure or to lessen their criticality. This is a step forward to FMEA.