IATF 16949 implementation

When MSA has to perform?After every calibration?Change of operators/ inspectors?

An MSA study must be carried out for each type of instrument specified in the control plan. MSA study must be done when new measuring equipment is purchased.If any automotive customer, in customer-specific requirements, is stated that there is an obligation to do MAS studies once a year; then MSA studies must be done once a year.

The MSA study should be repeated when the changing measurement system occurs. This includes topics such as measuring instruments or changing operators or measuring methods.      

When the instrument is repaired, the MSA study must be repeated. Normally, it is a good idea to do a gauge study, that is, a Type 1 study after calibration of the measurement device. In particular, Mercedes requests a Type 1 MSA study which is BIAS study after each calibration. 

When we have a large variety of parts or part numbers of various sizes, then how to perform MSA? For all part numbers?

When performing MSA, critical measures should be selected and prioritized accordingly. Smaller sizes should be chosen instead of wide.  MSA is not required for every part. Because the MSA study is done on the measuring instrument, not directly on the part. When choosing parts for MSA study, critical parts and critical features should be taken into consideration. If the variations in the process are largely due to special causes, first, special causes must be eliminated, and the process must be stabilized. Otherwise, the MSA results we get will not reflect the truth.

Is it necessary to mention Work instruction revision no. and date in PFMEA and Control plan?

No, it is not necessary. Just a document number is enough in the PFMEA and control plan. 

In PFMEA, each function/requirement has to be classified as minor, moderate, major or to mention only SC/CC wherever required?

No, it doesn't have to be. The first place to look is the customer drawing or the definition in customer specifications. Critical characteristics must be defined in these documents. It should definitely be included in FMEA and control plans, especially if there is a product safety issue. If not, the experience of the organization from the past and the types of complaints may show these characteristics. Such characteristics come from also the manufacturing process parameters, and these should be included in P-FMEA and control plan.

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