What UKAS accreditation covers

What UKAS is

UKAS, the United Kingdom Accreditation Service, is the national accreditation body appointed by the government. It assesses laboratories against the international standard ISO/IEC 17025 and, if they meet it, accredits them. Accreditation is not a one-off badge: UKAS re-assesses laboratories regularly and can suspend or withdraw it.

Accreditation is granted per test, not per laboratory

A laboratory is not accredited for everything it does. It is accredited for a defined list of methods, each for a defined type of sample, published by UKAS as the laboratory's schedule of accreditation. A laboratory can be fully accredited for metals in drinking water and run pesticides on the same bench with no accreditation at all. Both results come out on the same headed paper.

That is why "we use a UKAS accredited laboratory" tells you very little. It is true of almost every testing website, including those whose certificates carry a mix of accredited and unaccredited results. The question to ask is: which parameters?

Our answer: every one

Every parameter on every test we sell is within our laboratory's UKAS schedule of accreditation. We check this when we build a test and whenever the laboratory's schedule changes, and the figure on this page is calculated from our catalogue rather than typed in. If a parameter outside the scope were ever added, the test page would show it against that parameter and the figure here would drop.

Analysis is carried out by a UKAS accredited laboratory.

Why it matters to you

• A solicitor, lender, environmental health officer or inspector can rely on the whole certificate, not just part of it. For a property sale or a Private Water Supplies Regulations check, an unaccredited result may simply be refused.
• Accredited methods have known limits of detection and known uncertainty. A "not detected" on an accredited method means something precise; on an unaccredited one it may mean the method could not see that low.
• The laboratory's work on each accredited parameter is independently audited: calibration, proficiency testing, staff competence and record keeping.

How to check a certificate

An accredited certificate carries the UKAS symbol with the laboratory's accreditation number, and marks any result that is not covered by the accreditation, usually with a symbol or a note such as "not UKAS accredited". If a certificate carries no such marks and no accreditation number, assume nothing on it is accredited. You can look up any laboratory's schedule on the UKAS website to see exactly which methods and sample types it covers.

What we do not claim

Pozzani Pure Water Ltd is not itself a UKAS accredited organisation; the laboratory that analyses your sample is. Accreditation covers the analysis, not the sampling: the result describes the water in the bottle you sent, which is why the kit instructions matter. And a test reports the parameters listed on its page, not every substance that could conceivably be in water.