Glossary

49 CFR Part 40

The U.S. Department of Transportation regulation that governs all DOT-regulated workplace drug and alcohol testing.

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49 CFR Part 40 is the procedural rulebook for DOT-regulated drug and alcohol testing. It applies to safety-sensitive employees in transportation industries (trucking, aviation, rail, transit, pipelines, maritime) and establishes uniform procedures for collection, laboratory analysis, MRO review, and reporting.

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  1. 49 CFR Part 40 — Procedures for Transportation Workplace Drug and Alcohol Testing Programs — U.S. Department of Transportation

Related terms & pages

Glossary

SAMHSA

The U.S. Substance Abuse and Mental Health Services Administration — publisher of the Mandatory Guidelines for Federal Workplace Drug Testing Programs.

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Medical Review Officer (MRO)

A licensed physician trained to interpret drug-test results and serve as the medical buffer between the laboratory and the employer.