AS9100 Measurement Traceability

Airplane, aerospace, AS9100


Can a manufacturer use “reference only” M&M equipment to accomplish in-process checks as long as these items are verified later on by “Inspection” using calibrated and/or verified equipment?

Would all of the measurements have to be verified by properly calibrated equipment?


The practice of using “reference-only” devices for in-process measures is not noncompliant with the standard.  The formal inspections to accept product would require use of calibrated equipment.

In clause, the standard clearly states “the organization shall determine and provide the resources needed to ensure valid and reliable results when monitoring or measuring is used to verify the conformity of products and services to requirements.”  And in clause, “hen measurement traceability is a requirement, or is considered by the organization to be an essential part of providing confidence in the validity of measurement results…”

Users and auditors should look at formal inspections steps and final buy-off to determine if any nonconformities were escapes from in-process measurements being conducted without calibrated devices.  Customer complaints can also be analyzed to see if any escapes were a result of failed in-process inspections.  If so, then the organization did not properly determine and provide the appropriate resources.

Buddy Cressionnie

For more information on this topic, please visit ASQ’s website.

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