FAA Federal Aviation Regulations (FARS, 14 CFR)

(a) No person may smoke and no operator may permit smoking in any aircraft lavatory.

(b) Unless otherwise authorized by the Secretary of Transportation, no person may smoke and no operator may permit smoking anywhere on the aircraft (including the passenger cabin and the flight deck) during scheduled passenger foreign air transportation or during any scheduled passenger interstate or intrastate air transportation.

[Doc. No. FAA-2000-7467, 65 FR 36780, June 9, 2000]