Anyone in a safety-sensitive position in transportation must be tested for drug use, both pre-employment and on a random basis, as well as for suspected drug use. In airline operations, the following positions are subject to this testing:
Flight crewmember duties.
Flight attendant duties.
Flight instruction duties.
Aircraft dispatcher duties.
Aircraft maintenance and preventive maintenance duties.
Ground security coordinator duties.
Aviation screening duties.
Air traffic control duties.
In addition to the previously-screened marijuana, cocaine and heroin, as of January 2018 the drug tests for synthetic opioids.