AIAG/VDA’s FMEA Manual Is a Major Advance (my take on this subject)

[Bill Levinson]

AIAG/VDA’s FMEA Manual Is a Major Advance | Quality Digest

AIAG/VDA’s FMEA Manual Is a Major Advance
New process is qualitative rather than quantitative

An overview of the new AIAG/VDA FMEA Handbook, which I recommend very highly. The new approach is a major improvement on what we learned 15 or 20 years ago.

 

[John C. Abnet]

AIAG/VDA’s FMEA Manual Is a Major Advance | Quality Digest

AIAG/VDA’s FMEA Manual Is a Major Advance
New process is qualitative rather than quantitative
Good day @Bill Levinson ;
Do you care to share some examples? (i.e. expound on your "qualitative rather than quantitative? )

 

[Bill Levinson]

The article uses a Shigeo Shingo example in which the failure mode is a flange not contacting three reference planes in a jig. The Occurrence rating is determined not by frequency of occurrence (e.g. percent, or per million opportunities) but rather by the nature of the prevention control, which relies on worker vigilance--never very comforting in a Shigeo Shingo case study. The same goes for the Detection rating, because the detection control relies on the worker to notice the problem.

A jidoka detection control reduces the Detection rating to 2, again because of the nature of the control rather than any estimate or calculation of the likelihood that the problem will escape detection. Installation of plungers that hold the part squarely in the jig (if achievable) is similarly a prevention control that ought to reduce the occurrence rating to 2 or maybe 3 (previously determined quantitatively, as in occurrences per thousand or millions of opportunities, which is unlikely to be available in this application).