SAMHSA Certified Laboratories

Short Answer

Every DOT-regulated drug test must be analyzed at a laboratory certified by the Substance Abuse and Mental Health Services Administration (SAMHSA) under the HHS Mandatory Guidelines. The 40.3 definition of "Laboratory" requires an HHS-certified lab for DOT testing. SAMHSA maintains the current, official list of certified laboratories, and that list changes over time as labs are added, suspended, or removed from certification. Because of that, this article does not list specific laboratory names. Anyone who needs to confirm whether a specific lab is currently certified should check SAMHSA's official published list directly.

What Laboratory Certification Means

Who Certifies the Labs: SAMHSA, an agency of the Department of Health and Human Services, certifies laboratories that perform federal workplace drug testing, including DOT-regulated testing, under the HHS Mandatory Guidelines.
Why DOT Requires HHS Certification: DOT's own drug testing rule requires that a specimen collected under Part 40 be sent to an HHS-certified laboratory. A result from a lab that is not currently certified is not a valid DOT test result.
What Certification Covers: Certification addresses the laboratory's testing methods, quality control, chain of custody handling, personnel qualifications, and proficiency testing. A lab that loses certification, even temporarily, cannot process DOT specimens during that period.
Where to Find the Current List: SAMHSA publishes and updates the official list of certified laboratories. Because certification status can change, this list should be checked directly at the time it is needed rather than relied upon from a secondary source.

Applicable Regulations and Sources

49 CFR § 40.3, Definitions (Laboratory)
SAMHSA, HHS Mandatory Guidelines for Federal Workplace Drug Testing Programs
samhsa.gov (current list of certified laboratories)

Professional Observation

One question I sometimes get is whether an employee can request that their specimen be sent to a specific laboratory. That choice belongs to the employer and its service agent, not the employee, as long as the lab selected is HHS-certified. What an employee can request, if a primary specimen is verified positive, adulterated, or substituted, is testing of the retained split specimen at a different HHS-certified lab.

Primary Authorities

49 CFR § 40.3, Definitions
samhsa.gov

Questions About Your Test Result?

If you have questions about how your specimen was tested or reviewed, a DOT qualified Substance Abuse Professional or your MRO can help clarify the process.

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