Guides & comparisons

Verifying the Lab Itself: ISO 17025, A2LA-Accredited Labs and ILAC

To verify a peptide testing lab, take the accreditation body and certificate number from the report, look the lab up in that body's public register (A2LA, DAkkS, UKAS…) and read its scope, then check the body itself in ILAC's signatory directory. It takes about five minutes.

By the Peppies research desk · Published 3 August 2026 · Updated24 September 2026

Every other check in this cluster assumes something that usually goes unexamined: that the laboratory named on the certificate exists, is independent, and is competent to run the test it reported. Accreditation is claimed far more often than it is held — and the claim is easier to check than most people expect.

What is ISO/IEC 17025 accreditation?

ISO/IEC 17025 is the international standard for the competence of testing and calibration laboratories. It covers technical competence and the management system around it: personnel qualification, equipment calibration traceable to reference standards, method validation, evaluation of measurement uncertainty, sample handling and chain of custody, how results are reported, internal audits, and participation in proficiency testing where it exists for the method.

A laboratory is accredited to ISO 17025 by an accreditation body that assesses it on site and re-assesses periodically. Two consequences follow, and both get missed routinely.

Why does the accreditation scope matter?

A laboratory is not accredited in general. It is accredited for a defined scope: named methods, applied to named sample types, sometimes within specified measurement ranges. The scope is a published document — often several pages — and it enumerates exactly what is covered.

So the useful question is not “is this laboratory accredited?” It is “is this laboratory accredited for this test?” A laboratory accredited for elemental analysis by ICP-MS is not thereby accredited for peptide purity by reversed-phase HPLC. Both may be within its competence; only one is within its assessed scope.

A single report can legitimately mix accredited and non-accredited results. Good reports flag which is which explicitly rather than letting one mark cover the page.

Accredited or certified — what is the difference?

A small terminology point with real diagnostic value. Laboratories are accredited to ISO 17025. They are not certified to it — certification is what happens with management-system standards like ISO 9001. “ISO 17025 certified”, with no accreditation body named and no number given, is the phrasing of someone repeating a marketing line rather than reporting a status.

On its own it proves nothing. It is a reliable signal about who wrote the sentence.

How do you find A2LA-accredited labs — and check any lab in the ILAC registers?

An A2LA-accredited lab is a laboratory that A2LA — the American Association for Laboratory Accreditation — has assessed against ISO/IEC 17025 for a defined list of tests. To find one, search A2LA’s public directory of accredited organizations by laboratory name or certificate number and open its scope: only the tests listed there are accredited. The same two-step lookup works for any laboratory and any accreditation body.

Accreditation bodies accredit laboratories. Something has to underwrite the bodies, and that is ILAC — the International Laboratory Accreditation Cooperation, which operates a mutual recognition arrangement (MRA) among accreditation bodies and publishes a directory of its signatories.

That gives a clean two-step check:

1. Identify the accreditation body named on the certificate and confirm it is an ILAC MRA signatory using ILAC’s directory. This catches invented accreditation bodies — an official-looking mark from an organisation that accredits nobody.
2. Search that body’s own directory for the laboratory. Accreditation bodies publish searchable lists of the labs they accredit, with certificate numbers and scope documents. A2LA, the American Association for Laboratory Accreditation, is one such body and maintains a public directory of accredited organisations and their scopes.

If a certificate names an accreditation body that isn’t an ILAC signatory, or a laboratory that doesn’t appear in that body’s directory, you have your answer without reading another line of the report.

What does an accredited report look like?

Reports issued under accreditation generally carry the accreditation body’s mark, the laboratory’s accreditation or certificate number, and often a statement identifying which results fall inside the accredited scope. A mark without a number is decoration. A number is something you can type into a directory.

Worth stating plainly: the accreditation belongs to the laboratory, not to the sample. It says the lab is competent to run the method. It says nothing whatsoever about the material — that is what the results are for.

Which check does almost nobody perform?

A directory confirms that a laboratory exists and is accredited for a scope. It does not confirm that this certificate came from that laboratory. Only the laboratory can do that.

So contact them and ask whether report number X, dated Y, was issued by them. Two conditions make this worth doing properly.

Use contact details you obtained independently — from the accreditation body’s directory, or from the laboratory’s own site found separately. Never the phone number or email printed on the certificate you are checking. A fabricated certificate carries fabricated contact details, and calling them produces a confident confirmation from whoever wrote the document.

Interpret the answer carefully. Some laboratories confirm or deny a report number freely. Others treat client work as confidential and decline to discuss it at all. A polite refusal is a very different answer from “we have no record of that number”, and only the second is a finding. Either way you have learned something the document could not tell you.

This single step is the strongest verification available to anyone outside a laboratory, and it is almost never taken.

What if the lab has no accreditation?

Absence of accreditation is not disqualifying. It is expensive and slow to obtain, and competent laboratories operate without it — particularly smaller and newer ones.

What it changes is where the burden sits. An accredited laboratory has had its competence assessed by an independent third party against a published standard, and the result is something you can look up. An unaccredited laboratory may be excellent, but nobody outside it has checked, and you are back to trusting a name — which is the position a certificate of analysis was supposed to get you out of.

Is Janoshik accredited? A worked example with the lab most peptide buyers actually meet

Most certificates that circulate in European peptide forums and vendor pages carry one lab name: Janoshik Analytical, in the Czech Republic. It is worth walking through it, because it shows the difference between three things that get blurred together — a verified report, an accredited lab, and a tested vial.

What the lab does. Janoshik sells analysis to anyone who posts a sample: HPLC purity, mass-spectrometry identity, and for some products sterility and endotoxin as add-ons. It runs “blind” tests where the sample arrives without a vendor label, and it publishes a report for each task. Vendors like it because it is fast, priced per sample, and produces a report a customer can check.

How verification works. Every Janoshik report carries a QR code that resolves to a page under verify.janoshik.com. That domain belongs to the lab, not the vendor, so a vendor cannot forge a page there. The lab also keeps a public directory at public.janoshik.com, searchable by test number, product and supplier. Scan the code or search the number: if the lab’s page shows the same compound, batch and result as the PDF you were sent, the report is real.

What verification proves — and does not. It proves that the lab issued this report for a sample it received. It does not prove that the sample was your batch, that it was drawn by anyone other than the vendor, or that the vial in your hand came from the same run. The public directory is self-selected: labs test what they are sent, and vendors choose which reports to publish. A genuine report from a good batch can sit on a product page for months while a different batch ships under the same label. This is exactly why the earlier sections insist on batch numbers matching your label, not just a report existing.

Accreditation is a separate question. As of this writing, janoshik.com makes no ISO/IEC 17025 claim, and the report pages do not carry an accreditation-body symbol. That is not an accusation; it is a scope statement. Accreditation means an external body audited the lab’s methods, calibration and staff against ISO/IEC 17025 and re-audits them. A lab can produce competent HPLC work without it. But a report cannot borrow credibility from accreditation the lab does not hold, and vendor copy that says “ISO-accredited Janoshik test” is describing something that does not exist.

The two-minute registry check, applied. The Czech national accreditation body is ČIA (Český institut pro akreditaci), a signatory to the ILAC mutual recognition arrangement. To check any Czech lab’s accreditation, open ILAC’s signatory directory, confirm ČIA is listed, then search ČIA’s register of accredited bodies for the lab’s legal name and read its scope — the specific methods and matrices it is accredited for. A lab accredited for water analysis is not accredited for peptide purity. Do the same with A2LA for a US lab, UKAS for a British one, DAkkS for a German one, RvA for a Dutch one. If a lab’s name is not in its national register, treat its reports as unaccredited work: possibly good, but unaudited.

What to ask a vendor, in one line. “Which lab, which test number, and does the batch on the report match the batch on my vial?” A vendor who can answer all three has given you something you can verify yourself. One who answers only the first has given you a logo.

How does the whole chain fit together?

Vial → lot number → certificate → issuing laboratory → accreditation body → ILAC.

Every arrow is checkable, and every arrow is a place the chain can break. The first is the most commonly broken and the cheapest to test. This one is the least commonly tested. In between sit the fields on the certificate, the chromatogram behind the purity figure, and the questions no certificate answers at all.

The good news is that this check is per-laboratory, not per-vial: the lab doesn’t change between batches even though the lots do. Do it once, write down what you found, and keep it beside the lot-level records that a working tracking system already holds — which is the job Peppies does on a shelf so it doesn’t have to be done from memory.

ISO 17025, A2LA and ILAC are named here because they are real, public and checkable. Janoshik is named as a worked example of how to run the check, not endorsed or criticised. All of this concerns documentation for research-use-only materials, and none of it is advice about use.