(a) This section applies to an employee who performs a function listed
in appendix I or appendix J to part 121 of this chapter directly or by
contract for a part 121 certificate holder, a part 135 certificate holder,
or an operator as defined in §135.1(c) 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 or rating 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 or rating issued under
this part.