Understanding UKAS Accreditation: Why It Matters for Water Testing

What Is UKAS Accreditation?

UKAS — the United Kingdom Accreditation Service — is the sole national accreditation body recognised by the UK government. It assesses and accredits organisations that provide testing, calibration, inspection, and certification services. When a laboratory holds UKAS accreditation, it means that an independent, authoritative body has verified that the laboratory operates to internationally recognised standards — specifically ISO/IEC 17025 for testing and calibration laboratories.

UKAS accreditation is not a one-off award. Accredited laboratories are subject to regular surveillance assessments and must demonstrate ongoing compliance with the standard. This means that when you use a UKAS-accredited laboratory, you can be confident that the quality of testing is consistently maintained.

Why Does UKAS Accreditation Matter for Water Testing?

When it comes to Legionella and other microbiological water testing, the choice of laboratory matters enormously. Here is why UKAS accreditation is so important:

1. Legal Defensibility

ACOP L8 — the Approved Code of Practice for Legionella control — states that testing should be carried out by a competent laboratory. While ACOP L8 does not explicitly mandate UKAS accreditation, HSG274 (the associated technical guidance) strongly recommends using UKAS-accredited laboratories. In practice, if you ever need to demonstrate compliance to the HSE, an insurer, or a court, results from a UKAS-accredited laboratory carry significantly more weight than those from an unaccredited source.

2. Accuracy and Reliability

UKAS accreditation requires laboratories to validate their methods, use calibrated equipment, participate in proficiency testing schemes, and maintain rigorous quality management systems. This means that results from a UKAS-accredited laboratory are far more likely to be accurate and reproducible than those from an unaccredited lab.

3. Consistency Across Tests

Because accredited laboratories follow standardised methods (such as those published by the Health and Safety Executive and British Standards), results are comparable over time and between different laboratories. This is important for trend monitoring — a key part of any Legionella control programme.

4. Insurance and Liability

Many insurers require evidence of UKAS-accredited testing as part of their policy conditions for commercial properties. Using an unaccredited laboratory could invalidate your insurance cover in the event of a Legionella-related claim.

5. Peace of Mind

Ultimately, UKAS accreditation gives you confidence that your test results are trustworthy. When you are making decisions about the safety of your water system — and the health of the people who use it — that confidence is invaluable.

What Does ISO/IEC 17025 Require?

ISO/IEC 17025 is the international standard for the competence of testing and calibration laboratories. To achieve and maintain UKAS accreditation, a laboratory must demonstrate:

• Technical competence: Staff must be qualified and trained for the tests they perform.
• Valid methods: Testing methods must be validated and appropriate for the samples being tested.
• Calibrated equipment: All instruments must be regularly calibrated and maintained.
• Traceability: Measurements must be traceable to national or international standards.
• Quality management: The laboratory must have documented procedures, internal audits, and management reviews.
• Proficiency testing: The laboratory must participate in external proficiency testing schemes to verify the accuracy of its results.

How to Verify UKAS Accreditation

You can verify whether a laboratory holds UKAS accreditation by searching the UKAS online directory. Each accredited organisation is listed with its accreditation number, scope of accreditation, and the standards it is accredited to. Always check that the specific tests you require (e.g. Legionella culture, TVC, Pseudomonas) fall within the laboratory's accredited scope.

Our UKAS-Accredited Testing Kits

All of our water testing kits are analysed by a UKAS-accredited laboratory, ensuring that your results are accurate, reliable, and legally defensible. Our kits cover:

• Legionella testing — for hot and cold water systems, cooling towers, and other risk systems
• Total Viable Count (TVC) testing — for general microbiological water quality monitoring
• Pseudomonas testing — particularly important for healthcare settings and immunocompromised individuals
• Hot tub and spa water testing — for leisure operators and private pool owners

Each kit includes pre-labelled sterile sample bottles, full instructions, and a pre-paid return envelope. Results are delivered directly to you, along with a laboratory report that you can use as part of your compliance records.

If you have questions about which tests are right for your water system, get in touch with our team — we are happy to help.