This part applies to the following persons:

(a) All air carriers and operators certificated under part 119 of this chapter authorized to conduct operations under part 121 or part 135 of this chapter, all air traffic control facilities not operated by the FAA or by or under contract to the U.S. military; and all operators as defined in 14 CFR 91.147.

(b) All individuals who perform, either directly or by contract, a safety-sensitive function listed in subpart E or subpart F of this part.

(c) All part 145 certificate holders who perform safety-sensitive functions and elect to implement a drug and alcohol testing program under this part.

(d) All contractors who elect to implement a drug and alcohol testing program under this part.