49 C.F.R. § 655.21 Drug testing.
Title 49 - Transportation
(a) An employer shall establish a program that provides testing for prohibited drugs and drug metabolites in the following circumstances: pre-employment, post-accident, reasonable suspicion, random, and return to duty/follow-up. (b) When administering a drug test, an employer shall ensure that the following drugs are tested for: (1) Marijuana; (2) Cocaine; (3) Opiates; (4) Amphetamines; and (5) Phencyclidine. (c) Consumption of these products is prohibited at all times.
Title 49: Transportation
PART 655—PREVENTION OF ALCOHOL MISUSE AND PROHIBITED DRUG USE IN TRANSIT OPERATIONS
Subpart C—Prohibited Drug Use
§ 655.21 Drug testing.