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What are the requirements for drug testing commercial vehicle operators and employees who drive as part of the job?

The Omnibus Transportation Employee Testing Act of 1991 requires drug and alcohol testing for employees who operate commercial vehicles. The intent of the Act is to increase transportation safety by mandating such testing for individuals in safety-sensitive positions.

The Department of Transportation (DOT) publishes rules in accordance with the Act for employers that must conduct the testing. Employers in the aviation, trucking, railroad, mass transit, pipeline or maritime industries must implement required testing. DOT agencies, including the Federal Motor Carrier Safety Administration, the Federal Railroad Administration, the Federal Aviation Administration, the Federal Transit Administration, and the Pipeline and Hazardous Materials Safety Administration, as well as the U.S. Coast Guard have industry-specific regulations for testing employees who perform safety-sensitive functions.

The DOT has developed a decision tree to assist employers in determining if they are covered by the DOT drug and alcohol testing requirements.

The Act mandates pre-employment, reasonable suspicion, post-accident, random and follow-up/return-to-duty drug and alcohol testing of employees in positions requiring a commercial driver's license and defined as safety-sensitive. Employees covered by the Act should be tested under the following circumstances:

  • When assigned to a position requiring a commercial driver's license.
  • On a random basis.
  • After an accident that resulted in the employee being issued a citation for a moving vehicle violation or resulting in a fatality.
  • For reasonable cause based on observed behavior or appearance.
  • Before being allowed to return to a covered position after having tested positive for drug or alcohol abuse.

Although DOT regulations mandate the types of testing and the procedures to adhere to following a positive test result, the regulations do not address employment decisions such as hiring, firing or leaves of absence. These decisions are up to the employer, in accordance with other applicable laws such as the Americans with Disabilities Act (ADA).

For employees not covered by DOT regulations, just because an employee drives as part of his or her job does not mean that drug and alcohol testing is required. There may be practical reasons for implementing such a program, however. An employee who is in an accident while working can create financial liability as well as a negative public image for the company, and many employers choose to implement internal drug and alcohol testing policies in accordance with state laws.


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