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What Substances Are Tested?

What Employers Need to Know

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

Drug cutoff concentrations can be found on the Substance Abuse and Mental Health Services Administration Web site.

DOT alcohol tests identify alcohol concentration of 0.02 and greater.

NOTE REGARDING NON-DOT TESTING: DOT does not prohibit motor carrier employers from instituting a “company authority” testing program that is in addition to, and distinct from, the required DOT testing program. Under such non-DOT programs, employers could test for other drugs. DOT also does not prohibit employers from using tests of non-urine specimens under a non-DOT program. DOT regulations at §382.601 provide that employer materials supplied to drivers may include information on additional employer policies with respect to the use of alcohol or controlled substances, including any consequences for a driver found to have a specified alcohol or controlled substances level, that are based on the employer's authority independent of this part. Any such additional policies or consequences must be clearly and obviously described as being based on the employer's independent authority.

Learn more about testing procedures for employers >>

Learn more about the Drug and Alcohol Clearinghouse