Does calibration to ISO 6789 mean the laboratory is accredited?
Applies to: ISO 6789:2003, ISO 6789-1:2017, ISO 6789-2:2017 · Updated 2026-10-27
Technical review: Alston Hsiao (Chieh-Jen Hsiao), CTO, STAND
No; a statement that calibration follows ISO 6789 and evidence of laboratory accreditation must be checked separately. The former identifies the technical basis used; the latter requires corresponding accreditation information. A standard reference or calibration certificate alone is not enough to establish a laboratory's accreditation status.
First identify what the standard requires
In the 2017 edition, for example, Part 1 sets requirements for valid calibration of the measurement device and the basis for traceability. Part 2 also addresses the calibration system, calibration certificates for devices, and the contents of tool calibration certificates. These requirements provide a basis for examining the measurement work. They do not automatically confer accreditation on a provider that writes “to ISO 6789.”
When a clause refers to ISO/IEC 17025, check what that reference applies to. Part 2, Clause 4.3, concerns the laboratory issuing the measurement device's calibration certificate and also provides a route involving calibration by a laboratory maintaining the national measurement standard. Clause 8 requires the tool calibration certificate to conform to ISO/IEC 17025. Upstream calibration information for the device cannot simply be treated as proof that the organization calibrating your tool is itself accredited.
Find separate evidence for method, traceability, and accreditation
| What do you need to establish? | What should you read or verify? |
|---|---|
| Which method was used for this calibration? | The complete edition and part, tool identification, and actual measurement and result information |
| What is the basis for the measurement device's calibration? | Valid calibration documents for that device and traceability information, checked against the applicable part |
| Does the service provider hold the required accreditation? | The status and scope published by the accreditation body, matched to the laboratory and the service needed |
The final row is a purchasing check, not a separate accreditation application procedure established by ISO 6789. If you need an accredited service, ask the supplier for accreditation identification details, then verify the valid status and scope with the accreditation body. Check whether the required measurement activity, range, and method are covered. A company name or an image of a logo is not enough.
Ask both questions when reviewing the documents
First ask, “What measurement evidence does this document provide?” Then ask, “Does this service meet our separately specified qualification requirements?” Even with complete qualification information, you still need to check that the certificate corresponds to the tool in hand and the work requested. If all you have is a statement of the method used, accreditation status remains unverified.
For a document referencing the 2003 edition, likewise confirm the edition and your requirements first, then read it against that edition. This article does not apply the 2017 document requirements retroactively to the earlier edition or determine whether any particular laboratory is accredited. Acceptance of a report depends on the actual evidence and the agreement between the parties.