CAT.GEN.MPA.170 Psychoactive substances
(a) The operator shall take all reasonable measures to prevent a person boarding an aircraft or being on board an aircraft when that person is under the influence of a psychoactive substance and is behaving in such a way as to risk endangering the safety of the aircraft or of another person on board of the aircraft.
(b) The operator shall develop and implement a policy on the prevention and detection of misuse of psychoactive substances by flight crew members and cabin crew members and by other safety-sensitive personnel under its direct control, in order to ensure that the safety of the aircraft or its occupants is not endangered.
(c) The operator shall develop and implement an objective, transparent and non- discriminatory procedure for the prevention and detection of cases of misuse of psychoactive substances by its flight crew members and cabin crew members and other safety-sensitive personnel under its direct control.
(d) The operator shall inform the CAA of any case of misuse of psychoactive substances by any person to whom the procedure in point (c) applies as soon as reasonably practicable.