The AASHTO Accreditation Program: Serving the Hot Mix Asphalt Industry

The American Association of State Highway and Transportation Officials (AASHTO) has been accrediting hot mix asphalt testing laboratories under the AASHTO Accreditation Program since 1988. Laboratories must satisfy many quality system criteria, as well as participate in the AASHTO Materials Reference Laboratory (AMRL) on-site assessment and proficiency sample programs, in order to receive accreditation from AASHTO. Satisfying the requirements of the growing list of agencies specifying accreditation, often in various forms, made the first ten years a challenging experience for both the AAP and its accredited laboratories. AMRL and the testing laboratories involved in the AAP have dealt not only with multiple quality system standards but also with their evolving criteria as well. The development of the National Cooperation for Laboratory Accreditation will present more demands as the AAP moves into its second decade as an accrediting body. Analysis of AMRL proficiency sample data indicates that accreditation is beneficial to the construction industry and that the AAP meets its objective of promoting uniformity in the testing of construction materials.