ISO/IEC 17025

ISO/IEC 17025 — full title General requirements for the competence of testing and calibration laboratories — is the international standard against which calibration and testing laboratories are accredited. It specifies the general requirements for the competence, impartiality and consistent operation of laboratories, and applies to any organisation performing laboratory activities, whatever its size. The current edition is ISO/IEC 17025:2017; earlier editions appeared in 1999 (replacing ISO/IEC Guide 25) and 2005.

What the standard covers

The standard asks two things of a laboratory at once: that it is managed so that it produces consistent results, and that it is technically able to produce them. The 2005 edition split its requirements into management requirements and technical requirements; the 2017 edition keeps both ideas but regroups them into five clauses:

• General and structural requirements — how the laboratory is organised.
• Resource requirements — the people, facilities, equipment and external providers it relies on.
• Process requirements — the heart of the standard: the activities that make a result rest on accepted science and be technically valid.
• Management-system requirements — the quality-management tools that support the technical work.

UKAS lists what competence rests on in practice: trained staff, properly calibrated and maintained equipment, valid methods, traceability of measurements to national standards, accurate reporting and suitable facilities.

Accreditation vs certification

This is the distinction most buyers miss. Certification is an audit of whether an organisation conforms to a standard such as ISO 9001. Accreditation sits one rung higher: an accreditation body assesses the competence and impartiality of an organisation to carry out specific technical activities — UKAS calls it "checking the checkers". A laboratory is therefore accredited to ISO/IEC 17025, never "certified" to it.

Accreditation bodies are national — UKAS (United Kingdom), DAkkS (Germany), A2LA and ANAB (United States) among many others. Those that sign the ILAC Mutual Recognition Arrangement (ILAC MRA) have been peer-evaluated against ISO/IEC 17011 and accept each other's accredited results: "accredited once, accepted everywhere".

Accreditation is also specific: it covers only the activities on the laboratory's scope (schedule) of accreditation. A certificate from an accredited laboratory includes the results and the standards and methods used, and may carry the accreditation body's symbol — combined with the ILAC MRA mark when that body is a signatory. For calibration, ILAC's elements of traceability add a documented measurement uncertainty and an unbroken chain to a national or international standard.

	ISO/IEC 17025	ISO 9001
Purpose	Competence, impartiality and consistent operation of testing and calibration laboratories	A quality-management system for any organisation
Who assesses	A national accreditation body (UKAS, DAkkS, A2LA …)	A certification body
Output	Accreditation for a defined scope	Certification of the management system
What the customer gets	A specific measurement that is technically valid, traceable and stated with its uncertainty	A supplier that runs a documented quality system

Why it matters when buying calibration in Iraq and Kurdistan

A calibration certificate is only as good as the chain behind it. The first question is not "is the instrument calibrated?" but "against what reference, and how far does the chain go?" Barmaan's calibration certificates, issued from Erbil, state their traceability to NIST / UKAS reference standards.

Read the scope, not the logo — it lists the quantities and ranges the laboratory is accredited for, and nothing outside it is covered. Ask any laboratory:

• Which accreditation body accredits you, is it an ILAC MRA signatory, and can I find you in its directory?
• Is this exact measurement — quantity and range — on your scope?
• What are your reference standards traceable to, and when were they last calibrated?
• Will the certificate state the measurement uncertainty?

Related terms

Metrological traceability

The property of a measurement result whereby it can be related to a reference through a documented, unbroken chain of calibrations, each contributing to the measurement uncertainty (VIM 2.41). Traceability alone does not make the uncertainty adequate for a given purpose.

Measurement uncertainty

The quantified doubt attached to a result; every calibration in the chain contributes to it, which is why an accredited certificate states it.

Scope of accreditation

The schedule of specific activities a laboratory is accredited for — and nothing else.

ILAC MRA

Accreditation bodies peer-evaluated to ISO/IEC 17011 accept each other's accredited results, so a certificate from one signatory's laboratory is recognised under the others.