According to AIAG
1 guidelines, if your measurement system's variation is less than 10% of process's variation, then it is acceptable. To evaluate your process variation, compare the Total Gage R&R contribution in the %StudyVar column (%Tolerance, %Process) in your output with the values in the table.
| Percentage of process variation |
Acceptability |
| Less than 10% |
The measurement system is acceptable. |
| Between 10% and 30% |
The measurement system is acceptable depending on the application, the cost of the measurement device, cost of repair, or other factors. |
| Greater than 30% |
The measurement system is not acceptable and should be improved. |
Guidelines using variance components
This table contains corresponding guidelines using variance components. To evaluate your variance components, compare the %Contribution column in your output with the values in the table.
| Percentage of variance components |
Acceptability |
| Less than 1% |
The measurement system is acceptable. |
| Between 1% and 9% |
The measurement system is acceptable depending on the application, the cost of the measurement device, cost of repair, or other factors. |
| Greater than 9% |
The measurement system is not acceptable and should be improved. |
Important
The AIAG also states that the number of distinct categories into which the measurement system divides process output should be greater than or equal to 5.
1 Automotive Industry Action Group (AIAG) (2010).
Measurement Systems Analysis Reference Manual, 4th edition. Chrysler, Ford, General Motors Supplier Quality Requirements Task Force