Safety-sensitive workplaces or positions must adhere to the following Health and Human Services (HHS) or Nuclear Regulatory Commission (NRC) testing authority, or are part of one of the following agencies under the U.S. Department of Transportation (DOT):

• Federal Motor Carrier Service Administration (FMCSA)
• Pipeline and Hazardous Materials Safety Administration (PHMSA)
• Federal Railroad Administration (FRA)
• Federal Aviation Administration (FAA)
• Federal Transit Administration (FTA)
• U.S. Coast Guard (USCG)