Your Ultimate Guide to DOT Drug Testing

Since the U.S. Department of Transportation (DOT) is responsible for safety as people travel by car, train, boat, subway or airplane, they make sure their operators are completely drug and alcohol-free.

If you work for the DOT, you must comply with their strict substance abuse policies. For this reason, the DOT has drug and alcohol testing to identify any signs of substance abuse.

Are you wondering if you need DOT drug testing for your DOT job? Read more to find out what the DOT test involves and who needs to take it.

What Is a DOT Drug Test?

The Department of Transportation has specific requirements for substance abuse. The DOT only performs urine tests to detect any drug use. They use saliva and breath tube testing when looking for alcohol consumption.

The test is for any job that involves public safety. If DOT suspects substance abuse, they can give the test randomly. This often happens after a safety incident, such as an accident or suspicion of drinking on the job.

Who Has to Get DOT Drug Testing?

If you work in a safety-sensitive job for the DOT, you have to take both drug and alcohol tests. Any job that puts the public’s safety at risk requires testing.

Most likely, you would be tested if you’re recently hired, if you’re suspected of using drugs, or when you’re returning to your job after a violation. We could also require you for follow-up testing after substance abuse.

Here is an overview of the DOT jobs that require a DOT drug screen.


The aviation jobs include flight crews, flight attendants, air traffic controllers and flight instructors. If you have any of these positions at facilities that aren’t FAA or U.S. military, you need a drug test.

Commercial Drivers

If you drive commercial motor vehicles that weigh over 26,000 pounds, you’re required to get a drug test. This also includes commercial drivers who carry 16 or more passengers.


Any operator of a commercial vessel requires drug screening. Maritime screening includes synthetic opioids and prescription drugs. 


You need testing if your pipeline job involves the operation, maintenance, or emergency response. These positions include the oil, gas and pipeline industries.


Any railroad job involving signal service, train dispatchers or engine and train personnel require testing. Other positions requiring drug and alcohol testing are people who repair and maintain railroad tracks.


You need a DOT test if you’re a transit vehicle operator, mechanic, or security. Transit positions are mostly bus operators.

What Types of Drugs Does the DOT Test Screen?

The DOT urine test looks for the following illicit drugs:

  • Cocaine
  • Marijuana THC
  • Amphetamines
  • Phencyclidine
  • Methamphetamines
  • Opiates

Only the Department of Health and Human Services (HHS) certified DOT drug test laboratories test for drugs for the DOT.

Can You Refuse a DOT Drug Test?

If you refuse the DOT drug testing, DOT views it as a positive result. This means you’ll lose your job functions. Then, you’ll need to have a Substance Abuse Professional (SAP) evaluate you.

If the SAP thinks you need substance abuse counselling, you’ll have to complete it before you can resume working for DOT. You’ll also need to agree to DOT drug testing and have a negative reading.

Complying with DOT drug and alcohol testing ensures the safety of both the public and DOT employees.

If you found this article about DOT drug testing helpful, read our other helpful content that encourages you to live life to the fullest.