ISO/IEC 17025 is the international standard that specifies the general requirements for the competence of testing and calibration laboratories. It is the foundational accreditation standard for laboratories worldwide, including the major gemmological laboratories, assay offices, and metrological calibration facilities that underpin the gem and jewellery trade. ISO 17025 accreditation is the credential that allows a laboratory to issue reports recognised internationally and to participate in mutual recognition arrangements with other accredited laboratories worldwide.

Scope

The standard sets out the management system requirements and the technical requirements that a laboratory must meet to demonstrate that it operates competently, consistently, and impartially. Management requirements cover document control, internal audit, management review, corrective action, customer-complaint handling, and the maintenance of records. Technical requirements cover personnel competence, accommodation and environmental conditions, test and calibration methods including method validation, equipment calibration and maintenance, measurement traceability to national or international standards, sampling, handling of test and calibration items, ensuring the quality of results, and the reporting of results.

Compliance with ISO 17025 is verified by an external accreditation body, which sends an audit team to the laboratory to inspect documentation, observe procedures, witness assays or tests, and review the laboratory's measurement traceability and proficiency-testing performance. Accreditation is granted for specified scopes, listing the methods and parameters for which the laboratory is competent, and must be renewed at periodic intervals.

Accreditation bodies

National accreditation bodies operate ISO 17025 accreditation programmes within their jurisdictions, with mutual recognition through the International Laboratory Accreditation Cooperation (ILAC) Mutual Recognition Arrangement. The major gem and assay laboratories are accredited under their respective national bodies: GIA, IGI, and the American Gem Society Laboratory through the American Association for Laboratory Accreditation (A2LA) or ANAB; UKAS in the United Kingdom; COFRAC in France; Accredia in Italy; SAS in Switzerland; DAkkS in Germany; SCC in Canada; SAC SINGLAS in Singapore. The recognition arrangement means that an A2LA-accredited GIA report is recognised as competent in the United Kingdom and the European Union without further verification.

Use in the gem and jewellery trade

For gemmological laboratories, ISO 17025 accreditation is the standard credential that distinguishes a recognised major laboratory from a regional or commercial-only operation. Reports issued under ISO 17025 accreditation carry the laboratory's accreditation mark and a statement of the methods used, providing the buyer with traceable evidence that the report has been issued under audited and validated conditions. For assay offices, ISO 17025 accreditation is similarly the credential that allows national hallmarks to be recognised internationally, since the accreditation provides assurance that the underlying assays follow validated methods such as ISO 11210, 11426, and 11427.

For working trade members, ISO 17025 status is one of the criteria for choosing a laboratory for important grading or hallmarking work. The combination of an internationally recognised method (such as one of the ISO assay methods or the GIA grading protocol), an ISO 17025-accredited laboratory, and a national accreditation body within the ILAC arrangement constitutes the gold standard of international recognition for trade documentation.