252.17—Enforcement.
Air carriers and foreign air carriers shall take such action as is necessary to ensure that smoking by passengers or crew is not permitted in the passenger cabin or lavatories on no-smoking flight segments. Air carriers shall take such action as is necessary to ensure that smoking by passengers or crew is not permitted in no-smoking sections or at other times or places where smoking is prohibited by this part, and to maintain required separation of passengers in smoking and no-smoking areas.