Accreditation · ISO/IEC 17025
ISO/IEC 17025 — UKAS Accreditation for Testing Laboratories
A lab result without 17025 accreditation is not legally defensible. 17025 covers everything from the moment a sample enters the lab to the moment the certificate is issued — chain of custody, method, blind duplicate control, and analyst competence.
International Organization for Standardization / UKAS · ISO/IEC 17025:2017 · Status: Current
Scope
What it covers.
Sample receipt and chain of custody, polarised light microscopy (PLM) for bulk identification, phase contrast microscopy (PCM) for airborne fibre counting, transmission electron microscopy (TEM), method validation, uncertainty of measurement, proficiency testing, competence and impartiality.
Who it applies to
- Every asbestos testing laboratory claiming accredited status
- Analysts performing air monitoring under HSG248
- Surveying bodies commissioning bulk sample analysis
Key provisions
The duties, provision by provision.
Requires unbroken chain of custody from site to certificate
Every sample must be individually numbered, sealed, logged in, tracked through analysis and archived. Break in chain invalidates the result.
PLM for bulk, PCM for air, TEM for confirmation
Bulk samples are identified under polarised light microscopy against a reference collection. Airborne fibres are counted under PCM to WHO rules. TEM is reserved for confirmation or high-sensitivity applications.
Requires participation in inter-lab schemes
Every accredited lab participates in AIMS (Asbestos in Materials Scheme) and RICE (Regular Interlaboratory Counting Exchange) — routine external verification of accuracy.
Requires reporting of measurement uncertainty
For quantitative results (e.g. fibre concentration) uncertainty must be calculated and reported on the certificate.
In practice
How we apply it.
- All bulk sample analysis is performed by UKAS 17025 accredited laboratories under our chain of custody.
- Air monitoring is performed by our accredited analysts under 17025 to HSG248 methodology.
- Lab certificates are supplied with every survey and testing instruction — never a survey-only summary.
FAQs
Common follow-up questions.
Can any lab test asbestos samples?
In practice, no. Only UKAS 17025 accredited laboratories can produce legally defensible results, and every reputable survey report attaches the certificate.
What's the difference between 17020 and 17025?
17020 accredits an inspection body (the surveyor). 17025 accredits a testing laboratory (the analyst). A reputable consultancy holds both, either directly or through a documented sub-contract arrangement.
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