Certain terms used in the regulations in this subchapter are defined in this subpart.

The term accommodation space means any public space such as a hall, dining room, mess room, lounge, corridor, lavatory, cabin, office, hospital, cinema, game and hobby room, pantry that contains no cooking appliances, and a similar space open to the passengers and crew.

The term anniversary date means the day and the month of each year, which corresponds to the date of expiration of the Certificate of Inspection.

The term approved means approved by the Commandant unless otherwise stated.

The term cargo means combustible liquid, flammable liquid, or liquefied flammable gas unless otherwise stated.

The term cargo area means that part of a vessel that includes the cargo tanks and other tanks into which cargo or cargo vapors are intentionally introduced, holds containing these tanks, all intervening space within, between, below, or outboard of these tanks or holds, and the deck area over the length and beam of the vessel above these tanks, holds, or spaces.

The term cargo control station means a location that is manned during cargo transfer operations for the purpose of directing or controlling the loading or unloading of cargo.

The term cargo handling room means any enclosed space where cargo is pumped, compressed, or processed. Examples of cargo handling rooms are pump rooms, compressor rooms, and cargo valve rooms.

The term Category A machinery space means any space and trunks and ducts to such a space that contains:

(a) Internal combustion machinery used for main propulsion;

(b) Internal combustion machinery used for purposes other than main propulsion where the total aggregate power is at least 500 brake horsepower;

(c) Internal combustion machinery that uses a fuel that has a flash point of less than 43.3°C (110°F); or

(d) One or more oil fired boilers or oil fuel units.

The term certificated when applied to tank vessels refers to a vessel covered by a certificate of inspection issued by the Coast Guard; when applied to men employed on tank vessels, the term refers to a certificate of ability issued by the Coast Guard.

The term classification requirements means applicable rules and supplementary requirements of the American Bureau of Shipping, or other recognized classification society.

Under this designation shall be included all tank vessels normally navigating the waters of any ocean or the Gulf of Mexico 20 nautical miles or less offshore.

The term cofferdam means a void or empty space separating two or more compartments for the purpose of isolation or to prevent the contents of one compartment from entering another in the event of the failure of the walls of one to retain their tightness.

The term combination carrier means a tank vessel designed to carry alternatively liquid and solid cargoes in bulk.

The term combustible liquid means any liquid having a flashpoint above 80 °F. (as determined from an open-cup tester, as used for test of burning oils). In the regulations of this subchapter, combustible liquids are referred to by grades, as follows:

(a) Grade D. Any combustible liquid having a flashpoint below 150 °F. and above 80 °F.

(b) Grade E. Any combustible liquid having a flashpoint of 150 °F. or above.

The term Commandant means the Commandant of the Coast Guard.

The term Coast Guard District Commander means an officer of the Coast Guard designated as such by the Commandant to command all Coast Guard activities within his district which include the enforcement and administration of Subtitle II, Title 46, U.S. Code, Title 46 and Title 33, U.S. Code, and regulations issued under these statutes.

The term control space means an enclosed space in which is located a ship's radio, main navigating equipment, or emergency source of power or in which is located centralized fire recording or fire control equipment, but not including firefighting apparatus that must be located in the cargo area or individual pieces of firefighting equipment.

The term deadweight or DWT means the difference in metric tons between the lightweight displacement and the total displacement of a vessel measured in water of specific gravity 1.025 at the load waterline corresponding to the summer freeboard assigned according to 46 CFR, subchapter E.

The words flammable and inflammable are interchangeable or synonymous terms for the purpose of the regulations in this subchapter.

The term flammable liquid means any liquid which gives off flammable vapors (as determined by flashpoint from an open-cup tester, as used for test of burning oils) at or below a temperature of 80 °F. Flammable liquids are referred to by grades as follows:

(a) Grade A. Any flammable liquid having a Reid 1 vapor pressure of 14 pounds or more.

(b) Grade B. Any flammable liquid having a Reid 1 vapor pressure under 14 pounds and over 8 1/2 pounds.

(c) Grade C. Any flammable liquid having a Reid 1 vapor pressure of 8 1/2 pounds or less and a flashpoint of 80 °F. or below.

The term flame arrester means any device or assembly of a cellular, tubular, pressure, or other type used for preventing the passage of flames into enclosed spaces.

The term flame screen means a fitted single screen of corrosion-resistant wire of at least 30 by 30 mesh, or two fitted screens, both of corrosion-resistant wire, of at least 20 by 20 mesh, spaced not less than 1/2 inch or more than 1 1/2 inches apart.

The term flashpoint indicates the temperature in degrees Fahrenheit at which a liquid gives off a flammable vapor when heated in an open-cup tester. For the purpose of the regulations in this subchapter, flashpoints determined by other testing methods will be equivalent to those determined with an open-cup tester, as follows:

The term gas free means free from dangerous concentrations of flammable or toxic gases.

The term general rules and regulations means the requirements contained in this chapter.

Under this designation shall be included all tank vessels navigating the Great Lakes.

The term Headquarters means the Commandant (CG-CVC), Attn: Office of Commercial Vessel Compliance, U.S. Coast Guard Stop 7501, 2703 Martin Luther King Jr. Avenue SE., Washington, DC 20593-7501.

The term keel laying date means the date upon which progressive construction identifiable with a specific vessel begins, including construction of the first module or prefabricated section of the hull that is identifiable with that vessel.

The term lightweight means the displacement of a vessel in metric tons without cargo, oil fuel, lubricating oil, ballast water, fresh water, feedwater in tanks, consumable stores, and persons and their effects.

The term liquefied flammable gas means any flammable gas having a Reid vapor pressure exceeding 40 pounds, which has been liquefied.

Under this designation shall be included all tank vessels navigating the waters of any of the lakes, bays, or sounds other than the waters of the Great Lakes.

The term machinery space means any space that contains machinery and related equipment including Category A machinery spaces, propelling machinery, boilers, oil fuel units, steam and internal combustion engines, generators and centralized electrical machinery, oil filling stations, refrigeration, stabilizing, ventilation, and air conditioning machinery, and similar spaces and trunks to such spaces.

The terms marine inspector or inspector mean any person from the civilian or military branch of the Coast Guard assigned under the superintendence and direction of an Officer in Charge, Marine Inspection, or any other person as may be designated for the performance of duties with respect to the enforcement and administration of Subtitle II, Title 46, U.S. Code, Title 46 and Title 33, U.S. Code, and regulations issued under these statutes.

Under this designation shall be included all tank vessels normally navigating the waters of any ocean or the Gulf of Mexico more than 20 nautical miles offshore.

The term Officer in Charge, Marine Inspection, means any person from the civilian or military branch of the Coast Guard designated as such by the Commandant and who under the superintendence and direction of the Coast Guard District Commander is in charge of an inspection zone for the performance of duties with respect to the enforcement and administration of Subtitle II, Title 46, U.S. Code, Title 46 and Title 33, U.S. Code, and regulations issued under these statutes.

The term oil fuel means oil used as fuel for machinery in the vessel in which it is carried.

The term oil fuel unit means the equipment used for the preparation of oil fuel for delivery to an oil fired boiler, the equipment used for the preparation of heated oil fuel for delivery to an internal combustion engine, and any oil fuel pressure pump, filter, and heater that deals with oil at a pressure of more than 1.8 kilograms per square centimeter (25 p.s.i.) gauge.

The term permit refers to endorsement on the certificate of inspection, authorizing the presence on board of liquid flammable or combustible cargoes in bulk, issued by an Officer in Charge, Marine Inspection, for a tank vessel which is found to be in substantial compliance with the regulations in this subchapter.

(a) Pilot boarding equipment means a pilot ladder, accommodation ladder, pilot hoist, or combination of them as required by this subchapter.

(b) Point of access means the place on deck of a vessel where a person steps onto or off of pilot boarding equipment.

The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed places.

The term recognized classification society means the American Bureau of Shipping or other classification society recognized by the Commandant.

The term Reid vapor pressure means the vapor pressure of a liquid at a temperature of 100 °F., expressed in pounds per square inch absolute, as determined by the Reid Method as described in the American Society for Testing Materials Standard D 323 (incorporated by reference, see § 30.01-3), Method of Test for Vapor Pressure of Petroleum Products. This Standard is available at Headquarters for reading purposes or it may be purchased from the Society at 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.

Under this designation shall be included all tank vessels whose navigation is restricted to rivers and/or to canals, exclusively.

Self-propelled tank vessel means a self-propelled tank vessel other than a tankship.

Service spaces are spaces that are used for galleys, pantries containing cooking appliances, lockers, storerooms, paint and lamp rooms and similar spaces that contain highly combustible materials, laundries, garbage and trash disposal and stowage rooms, workshops other than those forming part of the machinery spaces, and similar spaces and trunks to such spaces.

The term spark arrester means any device, assembly, or method of a mechanical, centrifugal, cooling, or other type and of a size suitable for the retention or quenching of sparks in exhaust pipes from internal combustion engines.

The term tank barge means a nonself-propelled tank vessel.

The term tankship means a self-propelled tank vessel constructed or adapted primarily to carry oil or hazardous material in bulk in the cargo spaces.

The term tank vessel means a vessel that is constructed or adapted to carry, or that carries, oil or hazardous material in bulk as cargo or cargo residue, and that—

(a) Is a vessel of the United States;

(b) Operates on the navigable waters of the United States; or

(c) Transfers oil or hazardous material in a port or place subject to the jurisdiction of the United States.

The following ratings are established in part 13 of this chapter. The terms for the ratings identify persons holding valid endorsements for service in the ratings issued under that part:

(a) Tankerman-PIC.

(b) Tankerman-PIC (Barge).

(c) Restricted Tankerman-PIC.

(d) Restricted Tankerman-PIC (Barge).

(e) Tankerman-Assistant.

(f) Tankerman-Engineer.