Making Quality Your Top Priority

March 24, 2019


Using an accredited laboratory (lab) adds confidence the work being performed is completed in accordance with nationally and internationally recognized standards and procedures, and with proper equipment. The accreditation process involves an on-site lab assessment including detailed inspections of records and equipment. Firms must have management and technical staff that meet accreditation body requirements. When a company chooses a lab to become accredited, it is not an easy path to take. The firm must make quality a top priority.

An accredited lab is one that has taken the steps by an independent accreditation agency to gain formal recognition of technical competence in certain types of testing, calibration, and measurements. After any necessary corrective action response, submission, and resolution, the lab is added to the agency’s list of accredited labs, and may mention its accreditation in marketing materials. Most construction projects require third-party testing labs to be accredited.


The accreditations a lab chooses to obtain can depend on several factors. The scope of tests the laboratory performs may dictate what accreditations are best suited. The scope can include various subfields of Construction Materials Testing (CMT) to include cement, concrete, masonry, soil, rock, aggregate, asphalt mixtures, and steel. The accreditation required by a local jurisdiction or project specifications may drive the selection of the agency as well. Some of the accreditation agencies include AASHTO re:source (formerly AMRL), CCRL (Cement and Concrete Reference Laboratory), A2LA (American Association for Laboratory Accreditation), NVLAP (National Voluntary Laboratory Accreditation Program), ISO 17025, CMEC (Construction Materials Engineering Council) and USACE (United States Army Corps of Engineers). These agencies are typically used by labs performing testing for geotechnical and materials engineering services.

Terracon owns, operates, and maintains one of the largest networks of accredited and validated labs of any geotechnical engineering firm in the U.S. Terracon’s national laboratory resources allow us to process large volumes of test specimens quickly, accurately, and reliably, reducing risk of delays to your critical project schedule. And, with a local presence, we have in-depth familiarity with materials and specifications of numerous local, state, and federal agencies.

Terracon labs meet your needs with more than 140 materials and geotechnical laboratory locations throughout the U.S., including these national accreditations:

  • USACE validation – 48 locations
  • AASHTO accreditation – 95 locations
  • AASHTO accredited and USACE validated – 42 locations
  • ISO 17025 – 7 locations
  • CMEC – 8 locations
  • NVLAP – 1 location – Lab Code: 100315-0
  • A2LA – 5 locations – Cert Nos.: 1002.01, 1002.0, 479.01, 479.02, 479.05, 479.06

Local accreditations also available at many locations. Visit

Linda G. Dobkins, P.E., P.G., is a Senior Engineer in Terracon’s Cheyenne, WY office. She has more than 17 years of experience in construction materials testing services in the western region of the U.S.  Linda also performs Internal Quality Audits for Terracon’s laboratories throughout the Western Operating Group.

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