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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Trucking and Motorcoaches

Legacy ID
316

What are my employee and supervisor training responsibilities?

FMCSA controlled substance and alcohol testing regulations are in place to protect the safety of the traveling public. Public safety is best served if drivers are aware of the effects of alcohol and controlled substances on health, safety, and the work environment. Educating drivers and training...

What if my driver fails or refuses a test?

A driver fails 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 the driver to be immediately removed from performing safety-sensitive functions (i.e., driving CMVs) until successful completion of the...

Testing Procedures

What Employers Need to Know

The DOT drug and alcohol testing procedures are extensive and can be found in 49 CFR Part 40 Subpart E and Part 40 Subpart L, respectively. It is important for employers to know the testing process in order to ensure proper procedures are followed to...

What Substances Are Tested?

Which substances are tested? DOT drug tests require laboratory testing (49 CFR Part 40 Subpart F) for the following five classes of drugs: Marijuana, Cocaine, Opiates – opium and codeine derivatives, Amphetamines and methamphetamines, Phencyclidine – PCP

Who do I test?

Generally, all CDL drivers who operate commercial motor vehicles subject to the CDL requirements on public roads in the U.S. are performing safety-sensitive functions and are subject to DOT drug and alcohol testing (§382.103). This includes all full-time, part-time, intermittent, backup and...

Overview of Drug and Alcohol Rules for Employers

The United States Congress recognized the need for a drug and alcohol free transportation industry, and in 1991 passed the Omnibus Transportation Employee Testing Act, requiring DOT Agencies to implement drug and alcohol testing of safety-sensitive transportation employees. 49 CFR Part 40,...

Testing Procedures

The DOT drug and alcohol testing procedures are extensive and can be found in 49 CFR Part 40 Subpart E and Part 40 Subpart L, respectively. It is important for drivers to understand the testing process in order to ensure proper procedures are followed to protect their own...

What if I fail or refuse a test?

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...

Driver Resources and Downloads

CDL drivers seeking additional information on DOT drug and alcohol testing rules are encouraged to use the resources listed on this page. Videos: DOT Mock Collection Instructional Video DOT's 10 Steps to Collection Site Security and Integrity Video Brochures & Guides: Drug and Alcohol...

When does testing occur and what tests are required?

DOT drug and alcohol tests include: Pre-employment – An employer must receive a negative drug test result before permitting a CDL driver to operate a CMV. (§382.301). Post-accident – Drug and alcohol tests may be required after crashes according to the following chart (§382.303):