Federal Drug & Alcohol Testing Regulations

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The U.S. Department of Transportation (DOT) drug and alcohol testing regulations for commercial driver licensed (CDL) employees are contained in 49 CFR Part 382, and 49 CFR Part 40. These regulations can be found at: www.fmcsa.dot.gov. This brochure summarizes the regulations as they apply to CDL drivers, and is intended to better educate drivers about their rights and obligations as participants in a DOT drug and alcohol  testing program.

Who Must Be Tested?

All CDL drivers operating commercial motor vehicles (CMVs) (greater than 26,000 GVWR, or transporting more than 16 passengers, including the driver, or placarded hazardous materials) on public roadways must be DOT drug and alcohol tested. This applies to any driver required to possess a CDL, including those employed by Federal, State, and local government agencies, “owner operators,” and equivalently licensed drivers from foreign countries. Part-time drivers must also be included in an employer’s drug and alcohol testing program. Drivers who only operate CMVs on private property not open to the public do not require testing.

Required Tests

CDL drivers are subject to each of the following types of tests:

  • Pre-Employment – A new driver must be drug tested with a negative result before an employer can permit him to operate a CMV on a public road. Alcohol testing is permitted only if it applies to all CDL drivers. If a driver is removed from a random testing pool for more than 30 days, he must again be pre-employment tested.
  • Post-Accident– CDL drivers must be drug and alcohol tested whenever they are involved in a fatal accident, or receive a traffic citation resulting from an injury or vehicle-disabling accident. The alcohol test must occur within 8 hours, and the drug test must occur within 32 hours.
  • Random Testing – CDL drivers are subject to unannounced random testing. A driver may be directed to take a drug test even when at home in an off-duty status. Random alcohol testing may only occur when the driver is on-duty or immediately before or after.  Once notified to report for random testing, drivers must immediately report to the testing location. Delaying your arrival may be considered a refusal (see 49 CFR 40.191), which is equivalent to testing positive.
  • Reasonable Suspicion– DOT-trained supervisors can direct you to be drug or alcohol tested whenever you exhibit signs of drug or alcohol abuse. The decision must be based on observations concerning the appearance, behavior, speech, or body odors of the driver.
  • Return-to-Duty – Return-to-duty tests require “direct observation” as prescribed in 49 CFR 40.67. They are only required  after an employee has completed the “return-to- duty” process, and wants to return to work in a safety sensitive function (i.e., driving CMVs). They replace the pre-employment test for “positive” tested and “refusal” drivers.
  • Follow-Up – Follow-up drug and alcohol tests are required as prescribed by the substance abuse professional (SAP) who signs the returnto-duty report. They consist of a minimum of at least six unannounced directly observed tests conducted during the first 12 months following the returnto-duty test. The  SAP can prescribe follow-up testing for  a maximum of  5 years for drivers who have tested “positive” or “refused to test.” Follow-up testing is in addition to any selections for  random testing.

Testing Procedures

  • Once notified to report for testing, a CDL driver must report to the collection site immediately (To familiarize yourself with the collection process and any of the other aspects of the DOT drug and alcohol testing program, please  refer to: dot.gov/ost/dapc).
  • DOT drug testing only recognizes urinalysis as a valid means for drug testing. If problems are identified, you may be required to retest under direct observation. A driver is only permitted three hours to produce a urine specimen. Leaving the collection site before the process has been completed may be declared a “refusal.”
  • Once tested, the laboratory will report the analysis to a medical review officer (MRO). If the analysis indicates a positive result, the MRO will contact the driver to determine whether there are circumstances that would explain the positive result. If there are none, the MRO will report a positive result to the employer.

Controlled Substances

The regulations require 5-panel testing for the following classes of substances:

  • Marijuana
  • Cocaine
  • Opiates — opium and codeine derivatives
  • Amphetamines and meth amphetamines
  • Phencyclidine — PCP

For more information, visit  www.usdoj.gov/dea/concern


  • A positive test result or a refusal requires the driver to be immediately removed from operating any CMV on public roadways. The employer must provide you with a list of acceptable SAPs from which to choose to begin the “return-to-duty” process. This process must be completed before a positive or refusal driver can legally return to driving CMVs for any employer, including himself.
  •  The impact of testing positive or refusing to test can be devastating for a driver and his family. It often results in extended periods of unemployment, due to the time necessary to complete the “return-to-duty” process with a qualified SAP and the tendency of employers not to hire drivers with drug or alcohol histories.
  • Even after completing the “return-to-duty” process and finding employment, the additional return-to-duty and follow-up testing often adds increased stress and financial strain on the driver.


For additional research and reading on the Federal Motor Carrier Safety Administration’s Drug and Alcohol Testing Regulations, please visit our web site at: www.fmcsa.dot.gov/rules-regulations/topics/drug/drug.htm