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Drug Testing Laboratories

DOT COVID-19 Drug and Alcohol Testing Guidance...learn more


Drug testing laboratories certified by the Department of Health and Human Services receive urine specimens and test them to determine the presence of drugs. They also conduct validity testing to determine if the specimen has been adulterated or substituted.

A laboratory located in the U.S. is only permitted to participate in DOT drug testing only if it is certified by HHS under the National Laboratory Certification Program (NLCP) or in the case of a foreign laboratory, if it is approved for participation by the DOT with respect to Part 40.

As a reminder, only those laboratories identified under the HHS-Certified Laboratories list are permitted to participate in the DOT drug testing program. HHS-Certified Instrumented Initial Testing Facilities are not authorized for use in the DOT drug testing program.

Applicable Regulations

A laboratory participating in DOT drug testing must comply with the requirements in 49 CFR Part 40, as well as, all applicable HHS requirements. While it is important for the laboratory to be familiar with all aspects of 49 CFR Part 40, the laboratory should pay particular attention to the following:


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Last updated: Monday, April 6, 2020