ISO 17025 Requirements: Clause-by-Clause Checklist

Tilt-shift miniature of a technician ticking off a laboratory checklist at a clean bench — ISO/IEC 17025 is detailed where it matters: methods, equipment, traceability, uncertainty and reporting.

ISO/IEC 17025 sets out what a testing or calibration laboratory has to do to show it is competent and produces valid results. The 2017 edition is shorter and less prescriptive than the one it replaced, but it is detailed where it matters: methods, equipment, traceability, uncertainty and reporting. This is a clause-by-clause checklist of what the standard asks for and the evidence an assessor will look for.

Short answer

ISO/IEC 17025:2017 has five requirement clauses. Clause 4 covers impartiality and confidentiality. Clause 5 covers the laboratory’s structure and scope. Clause 6 covers resources: people, facilities, equipment, metrological traceability and external providers. Clause 7 covers the technical process from contract review to reporting. Clause 8 covers the management system, through Option A or Option B. NATA adds field-specific criteria on top.

Clause by clause

Clause	Requirement	Evidence an assessor will look for
4.1	Impartiality	Risks to impartiality identified and reviewed on an ongoing basis; commitment from management.
4.2	Confidentiality	Legally enforceable confidentiality commitments; controls on customer information.
5	Structural requirements	A legal entity; defined laboratory activities and scope; responsibilities and authorities; management of changes.
6.2	Personnel	Competence requirements for each role; training, supervision, authorisation and monitoring records.
6.3	Facilities and environmental conditions	Requirements documented; conditions monitored and recorded where they affect results.
6.4	Equipment	Equipment register, calibration program, intermediate checks, and handling of equipment that is out of service.
6.5	Metrological traceability	Traceability to SI units through calibration by competent providers or certified reference materials.
6.6	Externally provided products and services	Requirements defined, suppliers evaluated and monitored, including subcontracted testing.
7.1	Review of requests, tenders and contracts	Customer requirements understood and agreed, including any decision rule.
7.2	Selection, verification and validation of methods	Standard methods verified; non-standard and in-house methods validated, with records.
7.3 to 7.4	Sampling and handling of test or calibration items	Sampling plans where relevant; identification, transport, storage and disposal of items.
7.5	Technical records	Enough information to repeat the activity, including who did it and when.
7.6	Measurement uncertainty	Uncertainty evaluated for each test or calibration. See measurement uncertainty explained.
7.7	Ensuring the validity of results	Internal quality control and proficiency testing, with results reviewed for trends.
7.8	Reporting of results	Reports with the required content; statements of conformity with a decision rule; opinions and interpretations where offered.
7.9 to 7.10	Complaints and nonconforming work	A complaints process and a defined response to nonconforming work.
7.11	Control of data and information management	Validated software, data integrity, access control and backup.
8	Management system	Option A (8.2 to 8.9) or Option B (ISO 9001). See Option A vs Option B.

Where laboratories most often fall short

Method validation. In-house or modified methods used without validation records.
Measurement uncertainty. Estimates that exist but cannot be explained or are not kept up to date.
Decision rules. Pass or fail statements made without an agreed decision rule.
Proficiency testing. Gaps in participation, or poor results with no investigation.
Equipment. Calibration certificates filed but never reviewed against the laboratory’s own requirements.
Impartiality. A risk register that was written once and never revisited.

Using the checklist

Work through the table against your proposed scope, mark each line as in place, partly in place or missing, and turn the gaps into a plan. That is essentially a gap analysis, and our gap analysis audits follow the same approach. Before NATA assesses, an independent internal audit against the standard confirms the system is ready. The process itself is covered in our NATA accreditation guide.

How Streamline helps

We help laboratories work through the ISO/IEC 17025 requirements, build the missing pieces, and audit the system before NATA does. Accreditation itself is granted by NATA; our role is getting the laboratory ready for assessment and keeping the system working afterwards. Read about our ISO 17025 consulting, or talk to us about your laboratory.

More ISO 17025 guides

Frequently asked questions

What are the main requirements of ISO 17025?

ISO/IEC 17025:2017 has five requirement clauses: general requirements (impartiality and confidentiality), structural requirements, resource requirements (people, facilities, equipment, traceability and external providers), process requirements (from contract review to reporting and data control), and management system requirements under Option A or Option B.

Is ISO 17025:2017 still the current version?

Yes. ISO/IEC 17025:2017 is the current edition. It was reviewed and confirmed in 2023, and no new edition has been published.

What documents does ISO 17025 require?

The standard is less prescriptive than earlier editions, but laboratories still need documented methods, records of method verification and validation, equipment and calibration records, technical records for each test or calibration, competence and authorisation records, and management system documents. NATA’s criteria add field-specific requirements.

Do we need an internal audit before NATA assesses us?

Yes. Clause 8.8 (or the ISO 9001 equivalent under Option B) requires internal audits at planned intervals, and NATA will expect to see that the laboratory has audited itself against ISO/IEC 17025 before assessment.

General guidance only. This article is general information, not legal, financial, safety or compliance advice, and it does not take account of your specific circumstances. Streamline ISO Consultants are ISO management-system consultants, not lawyers or licensed advisers. Standards, laws and regulator guidance change, and details were correct only at the time of writing. Always seek professional advice before acting. See our full Disclaimer.