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What is DOT Drug Testing?

The Department of Transportation (DOT) requires drug testing if an employer overseen by:

  • Federal Motor Carrier Safety Administration
  • Federal Transit Administration
  • Federal Highway Administration
  • Federal Aviation Administration
  • Federal Railroad Administration
  • United States Coast Guard
  • Research and Special Project Administration

"CDL drivers operating commercial vehicles on public roads, inter-and/or intrastate motor carriers, drivers for various civic organizations, and drivers for faith-based organizations may be federally required to take drug test pre-hire, randomly, after an accident, upon reasonable suspicion, and on return to work." (Richard Matteucci, USA Mobile Drug Testing)

For more information click here.


What is Non-DOT Drug Test?

All employers, including those governed by the DOT, can establish a company protocol for drug testing.

But be aware: Non-DOT tests must be performed separately-i.e., separate samples and separate procedures. DOT testing must be done  first, and a positive DOT test Remains Positive, even if Non-DOT testing conducted later results in a negative.

Furthermore, company drug testing must comply with state and federal laws set out by the Department of Labor and American with Disabilities Act. When in doubt, employers can refer to SAMHSA guidelines.


Matteucci, R. (2017, September 28). What is the Difference Between DOT and Non DOT Drug Testing. Retrieved October 23, 2017, from