Septic tank means a water tight tank designed to receive sewage and to effect the adequate decomposition of organic matter in sewage by bacterial action;
oil tanker means a ship constructed or adapted primarily to carry oil in bulk in its cargo spaces and includes combination carriers and any “chemical tanker” as defined in Annex II of the present Convention when it is carrying a cargo or part cargo of oil in bulk.
chemical tanker means a ship constructed or adapted and used for the carriage in bulk of any liquid product listed in chapter 17 of the International Bulk Chemical Code;
Air navigation facility means any facility, other than one owned and operated by the United States, used in, available for use in, or designed for use in aid of air navigation, including any structures, mechanisms, lights, beacons, markers, communicating systems, or other instrumentalities or devices used or useful as an aid, or constituting an advantage or convenience to the safe taking off, navigation, and landing of aircraft, or the safe and efficient operation or maintenance of an airport, and any combination of any or all of such facilities.