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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Overview of Drug and Alcohol Rules for Employers

What Employers Need to Know

The United States Congress recognized the need for a drug and alcohol free transportation industry, and in 1991 passed the Omnibus Transportation Employee Testing Act, requiring DOT Agencies to implement drug and alcohol testing of safety-sensitive transportation employees. 49 CFR Part 40, or Part 40 as we call it, is a DOT-wide regulation that states how to conduct testing and how to return employees to safety-sensitive duties after they violate a DOT drug and alcohol regulation. Part 40 applies to all DOT-required testing, regardless of mode of transportation. For example, whether you are an airline covered by FAA rules or a trucking company covered by FMCSA rules, Part 40 procedures for collecting and testing specimens and reporting of test results apply to you. Each DOT Agency-specific regulation spells out who is subject to testing, when and in what situations for a particular transportation industry.

The DOT, along with FMCSA, adopted regulations requiring commercial motor vehicle (CMV) operators required to maintain a commercial driver's license (CDL) to be tested for alcohol and drugs. While you can hire various service agents to collect specimens, conduct laboratory analyses, medically review lab results and determine test outcomes; you cannot delegate your responsibility to comply with all applicable requirements and procedures of 49 CFR Part 40 and Part 382. This means that you are responsible for all actions of your employees, representatives, and agents (including service agents) in carrying out the requirements of the DOT agency regulations.

Employers can be held responsible for service agent errors and resulting civil penalty actions for noncompliance. Service agent violations may be directly addressed under the public interest exclusion (PIE) as described in 49 CFR Part 40 Subpart R. Additionally under the Safe Roads Act of 2012, Congress provided authority for civil penalty actions against service agents (49 USC 31306a) [Moving Ahead for Progress in the 21st Century Act ("MAP-21"; P.L. 112-141)].

This web site is intended to provide you with the basic information necessary to implement a DOT drug and alcohol testing program. It offers you many answers to questions that have been raised by employers trying to implement DOT testing programs, but it will not answer all of them. For those, we'll provide you with additional resources to give you what you need to be successful.

Learn more about the Drug and Alcohol Clearinghouse