DOT Drug & Alcohol Testing & the Clearinghouse
Drivers who need a CDL for their job are covered by federal drug and alcohol testing rules. A positive test or a refusal takes you off the road immediately, goes into a national database that every future employer checks, and can lead to your CDL being downgraded until you complete a return-to-duty process.
- CDL drivers
- Employers
When you can be tested
| Test | When |
|---|---|
| Pre-employment | Before you first drive for a new employer (drug test required) |
| Random | Unannounced, throughout the year; you must go right away when notified |
| Post-accident | After crashes involving a death, or an injury needing treatment away from the scene or a disabling tow when you got a citation |
| Reasonable suspicion | When a trained supervisor sees specific signs of use |
| Return-to-duty and follow-up | After a violation, before you can drive again and for a period afterward |
Drugs tested
DOT tests look for marijuana (THC), cocaine, amphetamines and methamphetamine, opioids (including oxycodone and similar prescription drugs), and PCP. A medical review officer contacts you to check for a valid prescription before reporting a positive for a prescription drug.
Marijuana: Even where marijuana is legal under state law, including for medical use, CDL drivers may not use it. CBD products can also contain enough THC to cause a positive test. DOT does not accept “it was CBD” as a defense.
Alcohol
- A breath alcohol concentration of 0.04 or higher is a violation.
- A reading of 0.02 to 0.039 takes you off duty for at least 24 hours.
- You may not drink within 4 hours before going on duty, or while on duty.
- After an accident that requires testing, don’t drink alcohol for 8 hours or until you’ve been tested.
- A DUI in your own car can also disqualify your CDL.
Refusals
Refusing a test counts the same as a positive. Refusals include not showing up in time, leaving the collection site, not providing a sample without a medical reason, and tampering with or substituting a sample.
The Clearinghouse
- Violations (positives, refusals and actual knowledge of use) are recorded in FMCSA’s Drug & Alcohol Clearinghouse.
- Employers must check it before hiring you and at least once a year while you work for them. You have to register and give consent for the full check.
- Drivers with a “prohibited” status lose the privilege to drive a CMV, and states downgrade the CDL until the return-to-duty process is finished.
- You can log in to see your own record and dispute errors.
Return to duty
- Evaluation by a DOT-qualified substance abuse professional (SAP)
- Completing the education or treatment the SAP requires
- A follow-up SAP evaluation
- A negative return-to-duty test
- At least 6 unannounced follow-up tests in the first 12 months back (and possibly more, for up to 5 years)
If you’re struggling
If you have a problem with alcohol or drugs, getting help before a violation is far better than after. Many employers have employee assistance programs. The SAMHSA helpline (1-800-662-4357) is free and confidential. See Mental Health & Suicide Prevention and Overdose & Naloxone.
Standards & references
- FMCSA Drug & Alcohol Clearinghouse
- 49 CFR Part 382: Controlled substances and alcohol use and testing
- 49 CFR Part 40: DOT testing procedures
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