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On Feb. 18, 2020, the Agricultural Improvement Act of 2018 (Farm Bill) removed hemp from the definition of marijuana under the Controlled Substance Act (CSA).

This made any hemp-derived products containing up to .03% tetrahydrocannabinol (THC) exempt from the CSA’s Schedule 1, which is a list of drugs considered to have the highest potential for abuse and no accepted medical uses.


The Department of Transportation’s (DOT) drug testing rules require employees in certain safety-sensitive positions to be tested for Schedule 1 drugs. As a result, these developments have raised questions about whether safety-sensitive employees may use a derivative of marijuana called cannabidiol (CBD) and whether these developments have any other effect on the drug testing rules.

Marijuana or CBD products cannot be used for medicinal purposes under the DOT; therefore, it is not a valid medical explanation for a commercial motor vehicle driver (CMV). The DOT has provided guidance on these frequently asked questions from employers.

This Compliance Overview provides a selected portion of the DOT’s frequently asked questions concerning CBD products and drug testing.

Links and Resources

DOT Office of Drug and Alcohol Policy and Compliance Notice for CBD products

DOT Office of Drug and Alcohol Policy and Compliance Notice for Medical Marijuana.

Employees Subject to DOT Drug Testing Rules

  • Pilots;
  • School bus drivers;
  • Truck drivers;
  • Train engineers;
  • Transit vehicle operators;
  • Aircraft maintenance personnel;
  • Fire-armed transit security personnel;
  • Ship captains; and
  • Pipeline emergency response personnel.


Employer Frequently Asked Questions

Does the legalization of use and possession of marijuana by a state or other country affect CMV drivers in the United States?

CMV drivers still have to abide by the Federal Motor Carrier Safety Regulations (FMCSRs) regardless of whether a state or other country legalizes marijuana. Marijuana is classified as a Schedule I controlled substance and, under the Federal Motor Carrier Safety Administration (FMCSA), a person is not physically qualified to drive a CMV if they use, are in possession of or under the influence of any Schedule 1 controlled substance, such as marijuana. State and other laws that legalize marijuana have not changed the FMCSA regulations. Thus, CMV drivers must not use, possess or be under the influence of marijuana while on duty or employed in a safety-sensitive position.

Can DOT-regulated, safety-sensitive employees use CBD products?

Safety-sensitive employees are subject to drug testing under 49 CFR Part 40. This regulation describes required procedures for conducting workplace drug and alcohol testing for the federally regulated transportation industry.

Notably, the DOT tests for THC on their drug testing. This means that the DOT doesn’t test specifically for CBD, but for the level of THC in an individual’s system. THC is the primary psychoactive component of marijuana. If the CBD product contains over .03% THC and is found when drug testing, it will be treated as a positive marijuana test under DOT regulations. Any product, including CBD products, with a concentration of more than 0.03% THC remains classified as marijuana—a Schedule I drug under the CSA that the DOT drug tests for. However, if CBD’s THC concentration falls under the .03% threshold, it is exempt from Schedule 1 under the CSA, which generally means an employee may use it. There is no oversight by the Food and Drug Administration to determine how much THC is in CBD. Employees should be cautious when purchasing and using CBD, as it may contain higher levels of THC than what is actually on the label. Under the DOT rules, use of CBD products is not a legitimate medical explanation for a positive drug test. Therefore, a medical review officer (MRO) must classify a test that shows the appropriate amount of THC as positive, even if the employee claims the positive result was due to CBD products. Employers should cover this in driver training and urge drivers to exercise caution when using CBD products.

Is medical marijuana acceptable for CMV drivers to use?

The DOT-regulated drug testing program does not allow use of medical marijuana by safety-sensitive employees, even if a state law has legalized it. Thus, medical marijuana use is not an acceptable medical explanation for a safety-sensitive employee’s positive drug test result. MROs may not verify a drug test as negative even if a physician recommended that the employee use marijuana for medicinal use.


This Compliance Overview is not intended to be exhaustive nor should any discussion or opinions be construed as legal advice. Readers should contact legal counsel for legal advice. © 2021 Zywave, Inc. All rights reserved.