US Accredited Calibration Lab Landscape 2026 README for us-calibration-lab-landscape-2026.csv Edition: first edition, September 2026 collection Revised: October 2026, wording only. The data file is unchanged. File: https://axiospec.com/us-calibration-lab-landscape-2026.csv 1,743 rows, 11 columns, UTF-8 Study page: https://axiospec.com/guides/us-accredited-calibration-lab-landscape Publisher: CaliTech LLC, doing business as Axiospec (https://axiospec.com) Contact: support@axiospec.com SOURCES Source: A2LA Accreditation Directory, customer.a2la.org, data collected 2 September 2026. https://customer.a2la.org Source: ANAB Accreditation Directory, search.anab.org, data collected 5 September 2026. https://search.anab.org Source: NVLAP Directory of Accredited Laboratories, www-s.nist.gov/niws, data collected 2 September 2026. https://www-s.nist.gov/niws/index.cfm Source: PJLA Accredited Organization Search, pjview.com, data collected 2 September 2026. https://www.pjview.com Source: IAS Directory of Accredited Laboratories, iasonline.org, data collected 4 September 2026. https://www.iasonline.org INDEPENDENCE This publication is independently produced by Axiospec. It is not sponsored, endorsed, or approved by ANAB, and reference to ANAB is solely for attribution of publicly available accreditation directory data. Nothing in this publication should be construed as a partnership, joint venture, or business relationship between Axiospec and ANAB, or as ANAB's certification, approval, or endorsement of Axiospec's products or services. The same applies to A2LA, NVLAP, PJLA and IAS. None of them sponsors, endorses or approves this publication, and nothing in it is a partnership, joint venture or business relationship with any of them. LICENCE Rows where accreditation_body is A2LA, PJLA, NVLAP or IAS (1,227 rows): Creative Commons Attribution 4.0 International (CC BY 4.0), https://creativecommons.org/licenses/by/4.0/ Attribute "Axiospec, US Accredited Calibration Lab Landscape 2026" and link the study page. Rows where accreditation_body is ANAB (516 rows): published with ANAB's written permission. They are NOT covered by CC BY 4.0. They may not be redistributed, sublicensed, sold, or built into a paid product or service. Any reuse needs ANAB's permission (ANAB@anab.org). WHAT A ROW IS A row is one directory record as the accreditation body publishes it. Rows are not laboratories, and counts of rows are not counts of laboratories. - A2LA lists accreditations per site rather than per company, so one organization can hold several rows. 722 A2LA US rows resolve to 665 distinct organization names. - ANAB folds satellite sites into a parent record. 43 of its 511 United States rows carry 171 further locations between them. - In its Forensic Calibration group ANAB reuses one certificate across many sites. The file carries every site as its own row, so within ANAB a certificate number is not unique. Four certificates cover 37 of the 65 Forensic Calibration rows. The largest, the Texas Department of Public Safety breath alcohol laboratory, covers 21 sites on one certificate. - For ANAB rows the scope_categories column carries ANAB's directory program groups, such as Calibration Labs or Forensic Calibration, not measurement disciplines. The column is not comparable between bodies. - The file carries all 516 ANAB rows from both groups regardless of status. The study's ANAB figures use the 486 that are Active and in the United States. Those figures count directory rows, not certificates: the 486 rows sit on 453 certificates, and the 64 Active Forensic Calibration rows sit on 31. RECORDS OUTSIDE THE FILTERS - ANAB's own United States country filter returned two laboratories in Ontario. They are in the file as Canadian rows, exactly as ANAB publishes them, and are not in the 486 or 511 United States figures. - Three ANAB Puerto Rico rows sit outside those two figures for the same reason. - The country column spells the United States three ways, as each directory publishes it: "United States" (A2LA, PJLA, IAS), "USA" (ANAB) and "US" (NVLAP). Filter on accreditation_body, or on all three. STATUS AND CURRENCY Directories change daily. Every row is a snapshot of its own collection date and is subject to change. A row may not reflect a laboratory's current accreditation status. Verify it in the accreditation body's own directory before relying on it. For ANAB that is https://search.anab.org On withdrawn ANAB rows the directory shows status text instead of an expiration date, so expiration_date is empty for those rows. 25 of ANAB's 511 United States rows are not Active. COLUMNS accreditation_body, lab_name, city, state, country, certificate_number, status, expiration_date, scope_categories, website, scope_document The study page's "Method and limits" section explains how each body's fields differ. CORRECTIONS To report an error in a row, email support@axiospec.com. We check it against the source directory and correct or remove the row.