How to Find an ASTM-Accredited Testing Lab

The buyer problem

Buyers searching for an "ASTM-accredited" lab often assume ASTM itself certifies labs, then get confused when a lab says it "follows ASTM standards" without any independent accreditation behind that claim — and the same confusion applies to calibration providers who reference ISO/IEC 17025 without a buyer knowing what that accreditation actually covers.

What a how to find an astm-accredited testing lab does

ASTM International publishes the test-method standards; it does not accredit laboratories. Accreditation is performed by a separate, independent accreditation body (such as A2LA or ANAB in the US) that audits a lab against ISO/IEC 17025 and issues a scope document listing the exact standards and methods the lab is approved to run — the same accreditation model applies to calibration laboratories accredited for specific measurement parameters.

Methods and techniques

• ISO/IEC 17025 general competence assessment
• On-site accreditation body audit and proficiency testing review
• Scope-of-accreditation issuance naming specific ASTM/ISO methods or calibration parameters
• Periodic reassessment and surveillance audits

What to verify before you retain

• Which body accredited them. Ask which accreditation body issued the certificate (A2LA, ANAB, and others operate in the US) and confirm that body is itself internationally recognized (an ILAC MRA signatory) rather than a self-styled certification mill.
• The actual scope document, not the certificate. The accreditation certificate itself often just states the lab is accredited; the scope document (usually a separate PDF) lists the specific test methods, standards, or calibration parameters actually covered — always request and read the scope, not just the certificate.
• Proficiency testing participation. Ask whether the lab participates in regular proficiency testing (blind round-robin sample exchanges) for the method you need, which is a required part of maintaining ISO/IEC 17025 accreditation and a useful ongoing quality signal.
• Expiration and renewal status. Accreditation is time-limited and requires periodic reassessment; confirm the certificate and scope you're shown are currently valid, not expired or under a lapsed renewal.

Questions to put in your RFP

1. Which accreditation body issued your ISO/IEC 17025 accreditation, and can you provide the current scope document?
2. Is the specific ASTM method (or calibration parameter) I need listed on that scope?
3. How recently was your last surveillance audit, and when does your current accreditation expire?
4. Do you participate in proficiency testing for this specific method, and can you share a recent PT result summary?
5. If a method I need isn't on your accredited scope, will the report be clearly labeled as unaccredited?

Red flags

• Claims to be 'ASTM-certified' or 'ASTM-accredited' as if ASTM itself issues that credential
• Shows only a certificate, refuses to produce the actual scope document
• Can't name which accreditation body assessed them
• Accreditation certificate is expired or the scope hasn't been updated in years
• Reports results without disclosing whether the specific method used is within accredited scope

Standards and governing bodies

Bodies referenced in this category. Listed for context; they do not endorse this index or any lab. Verify any credential directly with the issuing body.

ASTM

American Society for Testing and Materials. Publishes the consensus test-method standards labs are assessed against; ASTM itself does not accredit laboratories.

ISO

International Organization for Standardization. ISO/IEC 17025 is the general international standard for the competence of testing and calibration laboratories, used as the assessment basis by accreditation bodies worldwide.

A2LA

American Association for Laboratory Accreditation. A US-based, ILAC-recognized accreditation body that audits and accredits testing and calibration laboratories against ISO/IEC 17025.

ANAB

ANSI National Accreditation Board. A US-based, ILAC-recognized accreditation body (operated by ANSI) that accredits testing and calibration laboratories, certification bodies, and inspection bodies.

ILAC

International Laboratory Accreditation Cooperation. The international body whose Mutual Recognition Arrangement (MRA) is the benchmark for whether a national accreditation body's credentials are internationally recognized.