IATF 16949 clause 7.1.5.1.1 - Statistical studies shall be conducted

[Blaest]

IATF 16949 clause 7.1.5.1.1
"Statistical studies shall be conducted to analyse the variation present in the results of each type of inspection, measurement, and test equipment system identified in the control plan. The analytical methods and acceptance criteria used shall conform to those in reference manuals on measurement systems analysis. Other analytical methods and acceptance criteria may be used if approved by the customer..."

MSA 4th edition page 77:
"Since the final (total) variation is based on a combination of the process and measurement variation (total=process+MSA), When SPC is being applied for process control or collecting process data, and the control chart indicates that the process is stable and the total variation is acceptable, the measurement system can be considered acceptable for this use and does not require separate reevaluation."

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I just received a major in a transition audit due to an optical measurement machine that had a calibration certificate, a Type-1 MSA (50 measurements with a known and calibrated master) that was acceptable - the measurements from the machine is used to collect and evaluate SPC/CPK mainly Cpk>1,33 but also Cpk>1,67

To sum up:
-SPC is applied for process control
-The process is stable
-The total variation is acceptable

Objective evidence for the finding:"There is no MSA study made for the specific product the measurements made on the system. This process is the basic for calculating CpK values"

I challenged the auditor multiple times during audit without luck.
Should I accept this finding and why? Where is the 'shall'?

 

[Sebastian]

I think important element of observation is "specific product". In this IATF 16949 requirement starting point is control plan for specific product. We can't find word " product family" there, but I don't think that its intention is to perform separated MSA for each specific product.
What I would expect from organization is that documented process including MSA activity has also documented criteria to evaluate when one MSA is representative for set of characteristics. So, what are boundaries triggering organization to decide "but in this case we will make separate MSA"?

Mhmm based on MSA manual you have decided that MSA is not needed, but is it allowed according to IATF 16949?
Literary it is written there you can use methods presented in MSA manual, you can use acceptance criteria to evaluate results of MSA you have performed, but there is not written you can decide on whether do MSA or not, according to MSA manual. Complicated subject.

Any further rationale from auditor's side is available?

 

[Blaest]

Literary it is written there you can use methods presented in MSA manual, you can use acceptance criteria to evaluate results of MSA you have performed, but there is not written you can decide on whether do MSA or not, according to MSA manual. Complicated subject.

Thanks for your thoughts Sebastian,

However I notice there is a 'shall' in the IATF 16949 regarding the use of the MSA manual: "The analytical methods and acceptance criteria used shall conform to those in reference manuals on measurement systems analysis".

To MSA or not to MSA: to me (and the manual) Cpk includes the variation evalutated in the MSA - however the MSA would tell more detailed information - but that is really not the question as long as the evaluation shows a stable process is it?
The MSA manual even states:" If an out-of-control condition or nonconformance is found in this situation, the first thing that should be done is to evaluate the measurement system"

Rationale from auditor was like:"That is not the intention.." - however I don´t see the shall, not even when reading between the lines.

Just to clarify: I do find MSA a useful tool, we do perform MSA´s and I have no intention to state that we do not need to perform MSA in general - however I do find it hard to justify the finding!

 

[Golfman25]

The fundamental problem is that the standard has a shall and then refers to a guidance document full of ifs, buts, and guidelines. I think your argument makes sense from the plain reading of your cites. But over the years they have really cracked down on msa stuff. It certainly isn't a major by any reasonable person, but who says IATF et. Al. Are reasonable. I think you should appeal, but don't expect much. Good luck.