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Drug and Alcohol Rules Every CDL Driver Must Follow

Part 382, Subpart B lists what CDL drivers may not do with alcohol and drugs. Each rule also says what an employer may not allow. Here is each rule in plain English.

Updated September 28, 2026 · Checked against the federal regulations

First, what "safety-sensitive" means

Most of these rules apply while a driver is performing safety-sensitive functions. That is not just driving. It covers all time from when a driver starts work, or must be ready to work, until the driver is relieved from all work.

• Waiting to be dispatched at a terminal, shipper, or other property.
• Inspecting, servicing, or conditioning a CMV.
• Time at the driving controls.
• Other time in or on a CMV, except resting in a sleeper berth.
• Loading, unloading, or supervising loading.
• Repairing or staying with a disabled vehicle.

The alcohol rules

There is a separate rule for results from 0.02 to less than 0.04. It is not a violation of Subpart B, but the driver must stay off safety-sensitive work until the next regular duty period, and for at least 24 hours (382.505).

• 0.04 or higher (382.201): A driver may not report for or stay on duty with an alcohol concentration of 0.04 or greater.
• On-duty use (382.205): No drinking alcohol while performing safety-sensitive functions.
• Pre-duty use (382.207): No safety-sensitive work within 4 hours after using alcohol.
• After an accident (382.209): A driver who must take a post-accident alcohol test may not use alcohol for 8 hours after the accident, or until tested, whichever comes first.
• "Alcohol use" includes any drink or medicine that contains alcohol.

Refusing a test

Under 382.211, a driver may not refuse a required pre-employment, post-accident, random, reasonable suspicion, return-to-duty, or follow-up test. A refusal is treated like a violation.

Refusal covers more than saying no. Examples include not showing up in a reasonable time when told to test, leaving the site before testing is done, and not providing a specimen. Owner-operators who do not show up when called by their C/TPA have also refused.

The drug rules

Employers may require drivers to tell them about any therapeutic drug use (382.213(d)).

• Schedule I drugs (382.213(a)): A driver may not report for or stay on duty after using any Schedule I drug. Marijuana is Schedule I.
• Other controlled substances (382.213(b)): Not allowed unless prescribed by a licensed medical practitioner who knows the driver's medical history and has said the drug will not affect safe driving.
• Positive tests (382.215): A driver may not report for duty or perform safety-sensitive work after testing positive, or after adulterating or substituting a specimen.

What employers must do

Each rule also binds the employer. You may not let a driver work if you know of a violation. For some rules, the trigger is "actual knowledge": seeing the use yourself, hearing it from a previous employer, a DUI citation in a CMV, or the driver's own admission.

After a violation, the driver must be removed from safety-sensitive work (382.501). The driver may not operate a CMV again until the return-to-duty process under Part 40, Subpart O is complete (382.217). Violations also get reported to the Clearinghouse.

Pact Compliance can help you train drivers on these rules and keep your policy up to date.

Common questions

Sources

• 49 CFR 382.201 (eCFR)
• 49 CFR 382.205 (eCFR)
• 49 CFR 382.207 (eCFR)
• 49 CFR 382.209 (eCFR)
• 49 CFR 382.211 (eCFR)
• 49 CFR 382.213 (eCFR)
• 49 CFR 382.215 (eCFR)
• 49 CFR 382.107 Definitions (eCFR)
• 49 CFR 382.217, 382.501, 382.505 (eCFR)