ISO 17025 accreditation means an outside body has checked that a lab can do specific tests or calibrations well and report them reliably. It is not a seal that says every result from that lab is right. It is a badge with edges, and the edges are written down in a document called the scope.
What the standard covers
ISO/IEC 17025 is the international standard for testing and calibration laboratories. Its full title is "General requirements for the competence of testing and calibration laboratories." The current version is the third edition, published in November 2017. It came out under ISO's committee on conformity assessment, known as CASCO.
The standard looks at more than machines. It asks whether the staff are trained, whether the equipment is checked, whether the methods are valid and whether the lab keeps records. It also asks the lab to stay impartial, so that money or pressure from a client does not steer a result.
The 2017 edition replaced the 2005 edition. If you see an older certificate, check which edition it names.
Sources: ISO, ISO/IEC 17025:2017 catalogue page (publication date 2017-11, edition 3, technical committee ISO/CASCO), as archived April 3, 2024.
Who gives the badge
A lab does not award itself accreditation. A separate organization, called an accreditation body, does it. The body sends assessors who review the lab's quality system and watch its staff work. If the lab passes, it is accredited for a stated list of work. The body then comes back from time to time to check again.
This is different from a lab simply saying it meets a standard on its own say-so. It is also different from ISO 9001 certification, which covers a quality system for any kind of business and does not say a lab can run a given test.
In the United States, one such body is A2LA. Its home page lists ISO/IEC 17025 for testing and calibration laboratories as one of its programs. Other countries have their own bodies.
Sources: A2LA, home page, as archived March 27, 2024; ISO, ISO/IEC 17025:2017 catalogue page.
Why a badge from one country can count in another
Accreditation bodies join peer groups so that their work can be trusted across borders. The global group for labs is ILAC, the International Laboratory Accreditation Cooperation. It runs the ILAC Mutual Recognition Arrangement, often called the ILAC MRA.
ILAC says the bodies that sign this arrangement have been peer evaluated against another standard, ISO/IEC 17011, to show they are competent. The goal is summed up in a phrase on its page: "accredited once, accepted everywhere." In plain terms, a result from a lab accredited by a signatory body should be easier to accept in another country without repeat testing.
That is the reason to ask who accredited the lab. A badge from a body that is a signatory carries more weight than one from an unknown group.
Sources: ILAC, ILAC MRA and Signatories page, as archived April 3, 2024.
What scope means and why it matters
Scope is the most important word on an accreditation record. The scope is the list of tests, methods, materials and ranges the lab is accredited for. Accreditation covers that list and nothing more.
Here is an example. A lab might be accredited to measure metals in water. The same lab may also offer a test for something else, such as a vitamin in a capsule. If that second test is not on the scope, the badge does not apply to it. The lab can still run the test. It just has no outside check behind that test.
Scopes change. A2LA's own site shows a customer story about a lab asking to add methods to its scope so a client could release a project. That is how it works in practice. A lab adds methods over time, and each addition is assessed.
So when a report says "ISO 17025 accredited," ask one more question. Is this exact test on the scope?
Sources: A2LA home page, customer case study, as archived March 27, 2024; ISO/IEC 17025:2017 catalogue page.
How to check a lab yourself
You do not need to take a logo on faith. A few steps take only minutes.
- Find the name of the accreditation body on the report or on the lab's website.
- Search the lab in that body's public directory. A2LA, for one, links a "Search Organizations" tool from its site.
- Open the lab's scope. Look for the test or method on your report.
- Check that the accreditation is current and that the lab's name and address match.
- Confirm that the body is on the ILAC list of signatories if you care about acceptance abroad. The ILAC page offers a signatory search that lists each body and the scope of its recognition.
If a lab will not tell you who accredited it, or the name does not appear in any directory, treat the badge as unproven.
What the badge cannot tell you
Accreditation speaks to a lab's competence and process. It does not say anything about the product being tested. It also does not mean no error can happen. It lowers the odds and gives you a way to ask hard questions.
Use it as one piece of evidence, next to the method named on the report, the date of the test and the lab's independence from the seller. A good badge on the right scope is a strong sign. A badge with no scope is only a logo.
Sources: ISO, ISO/IEC 17025:2017 catalogue page; ILAC, ILAC MRA and Signatories page; A2LA, home page; all as archived by April 3, 2024.