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                        Drug & Alcohol TestingIn This Section
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          Find the local field offices in your state
      
      
      
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      1200 New Jersey Avenue SEWashington, DC 20590United States
      
          
    **Phone:** 800-832-5660
    If you are deaf, hard of hearing, or have a speech disability, please dial 7-1-1 to access telecommunications relay services.
                
                What if I fail or refuse a test?
    

    
    
          What CDL Drivers Need to Know

You fail a drug or alcohol test by testing positive to a drug test, or registering a 0.04 or greater alcohol content. Either of these results requires you to be immediately removed from performing safety-sensitive functions (i.e., driving CMVs) until successful completion of the return-to-duty process with a DOT-qualified substance abuse professional.

Your refusal to submit to a drug or alcohol test is generally equivalent to testing positive to a drug or alcohol test. You must immediately be removed from performing safety-sensitive functions (i.e., driving CMVs) until successful completion of the return-to-duty process with a DOT-qualified substance abuse professional. The DOT regulations outline refusals to test for drugs and alcohol. Some refusals are determined by medical review officers (49 CFR Part 40 Subpart G) and alcohol technicians (49 CFR Part 40 Subpart N). For others, the determination is the employer’s responsibility. Refusals to submit to a drug or alcohol test are defined in §382.107. The employee handbook available on the ODAPC Web site provides examples of conduct that the regulations define as refusing a test (49 CFR Part 40 Subpart I and Subpart N) and what happens if you test positive, refuse a test, or violate FMCSA regulations. It is, therefore, critical to understand the specific circumstances that define a refusal, which can be found in §40.191, §40.261 and §382.107.

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          Last updated: Thursday, July 22, 2021 U.S. DEPARTMENT OF TRANSPORTATION

**Federal Motor Carrier Safety Administration**

1200 NEW JERSEY AVENUE, SE

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