Commonwealth Consolidated Regulations Commonwealth Consolidated RegulationsThe operator, or a crew member, of an aircraft for a flight may prohibit a person from boarding the aircraft if there are reasonable grounds to believe that the person is affected by a psychoactive substance to an extent that may present a hazard to the aircraft or to a person on the aircraft.
Note: This Subpart does not apply to the operation of an aircraft if Subpart 121.F, 133.F, 135.F or 138.F applies to the operation: see regulation 91.035.