AASHTO Accreditation Program

The Louisiana DOTD Materials and Testing Section Laboratory located in Baton Rouge, Louisiana, currently holds certificates of accreditation to signify proficiency in the Quality Management System, Asphalt Binder, Emulsified Asphalt, Asphalt Mixture, Soil, Aggregate, Concrete, Cement, Pozzolan, Slag Cement, and Iron and Steel. Please visit the AASHTO Accreditation Program Directory for a list of currently accredited test methods.

The American Association of State Highway and Transportation Officials (AASHTO) established the Accreditation Program in June 1988. The objective of the accreditation program is to provide a mechanism to formally recognize the competency of a testing laboratory to perform specific tests on construction materials. The program is structured to verify that participating laboratories comply with the appropriate ASTM and AASHTO Standards or Recommended Evaluation Practices.

Accreditation is dependent upon meeting several respective parameters:

The establishment and implementation of a Quality Management System (QMS) for Construction Materials Testing Laboratories, per AASHTO R 18. The QMS documents the activities associated with laboratory policies, such as standard operating procedures, employee qualifications, standard forms, charts, equipment listings, in-house calibration procedures, and test reporting. The Laboratory Quality Management System serves primarily as a record-keeping method to assist the accredited laboratory in achieving its quality objectives.
On-site inspections are performed routinely every 18 to 24 months by a qualified inspection agency through the AASHTO Accreditation Program. The inspections consist of a review of the Laboratory Quality Management System, an examination of the laboratory's facilities, equipment, test apparatus, and calibration records, as well as an evaluation of the ability of laboratory technicians to conduct the specified tests on construction materials by ASTM and AASHTO standard methods of test. If any deficiencies are noted during the inspection, the accredited laboratory must provide the AASHTO Accreditation Program with satisfactory evidence within 60 days, noting that all deficiencies were corrected or that action is being taken to correct the deficiency. Failure to respond or correct deficiencies can result in having accreditation revoked.
Proficiency testing is used to evaluate the laboratory's performance. The samples are forwarded to all participating laboratories. The specific tests are performed, and results are entered into a database for analysis and ratings. The laboratory later receives a final report indicating how the laboratory's results and ratings compare with those of the other participating laboratories. If low ratings are obtained on proficiency samples, the accredited laboratory must perform a root cause analysis and corrective action within 60 days, then report the finding to the laboratory’s Quality Manager. Failure to respond to low ratings can result in having accreditation revoked.
The AASHTO Accreditation Annual Review Form must be completed yearly to ensure compliance with the AASHTO Accreditation Program.

The AASHTO Accreditation Program is available to all laboratories, including independent laboratories, manufacturers' in-house laboratories, university laboratories, and governmental laboratories.

In September 1988, the Louisiana DOTD became the first state transportation agency in the country to have its central testing laboratory (the Materials and Testing Section), located in Baton Rouge, Louisiana, accredited under this nationwide program.