14 CFR 120.215: Covered employees.

(a) Each employee, including any assistant, helper, or individual in a training status, who performs a safety-sensitive function listed in this section directly or by contract (including by subcontract at any tier) for an employer as defined in this subpart must be subject to alcohol testing under an alcohol testing program implemented in accordance with this subpart. This includes full-time, part-time, temporary, and intermittent employees regardless of the degree of supervision. The safety-sensitive functions are:

(1) Flight crewmember duties.

(2) Flight attendant duties.

(3) Flight instruction duties.

(4) Aircraft dispatcher duties.

(5) Aircraft maintenance or preventive maintenance duties.

(6) Ground security coordinator duties.

(7) Aviation screening duties.

(8) Air traffic control duties.

(9) Operations control specialist duties.

(b) Each employer must identify any employee who is subject to the alcohol testing regulations of more than one DOT agency. Prior to conducting any alcohol test on a covered employee subject to the alcohol testing regulations of more than one DOT agency, the employer must determine which DOT agency authorizes or requires the test.