(a) This section applies to an employee who performs a function listed in appendix I to part 121 or appendix J to part 121 of this chapter directly or by contract for a part 121 air carrier, a part 135 air carrier, or for a person conducting operations as specified in §135.1(a)(5) of this chapter.

(b) Refusal by the holder of a certificate issued under this part to take a drug test required under the provisions of appendix I to part 121 or an alcohol test required under the provisions of appendix J to part 121 is grounds for:

(1) Denial of an application for any certificate, rating, or authorization issued under this part for a period of up to 1 year after the date of such refusal; and

(2) Suspension or revocation of any certificate, rating, or authorization issued under this part.