While on board a vessel inspected, or subject to inspection, under Chapter 33 of Title 46 United States Code, a crewmember (including an officer), pilot, or watchstander not a regular member of the crew:
(a) Shall not perform or attempt to perform any scheduled duties within four hours of consuming any alcohol;
(b) Shall not be intoxicated at any time;
(c) Shall not consume any intoxicant while on watch or duty; and
(d) May consume a legal non-prescription or prescription drug provided the drug does not cause the individual to be intoxicated.
[CGD 84-099, 52 FR 47532, Dec. 14, 1987, as amended at USCG-2006-24371, 74 FR 11211, Mar. 16, 2009]