46 C.F.R. § 125.160
Definitions.
Cite as 46 C.F.R. § 125.160 (2026)
Each term defined elsewhere in this chapter for a particular class of vessel applies to this subchapter unless a different definition is given in this section. As used by this subchapter—
Accommodations
includes spaces such as at least the following:
(1) A space used as a messroom.
(2) A lounge.
(3) A sitting area.
(4) A recreation room.
(5) Quarters.
(6) A toilet space.
(7) A shower room.
Anniversary date
means the day and the month of each year, which corresponds to the date of expiration of the Certificate of Inspection.
Anti-exposure suit
means a protective suit designed for use by rescue boat crews and marine evacuation system parties.
Approval series
means the first six digits of a number assigned by the Coast Guard to approved equipment. Where approval is based on a subpart of subchapter Q of this chapter, the approval series corresponds to the number of the subpart. A listing of current and formerly approved equipment and materials may be found on the Internet at:
http://cgmix.uscg.mil/equipment.
Approved
means approved by the Commandant, unless otherwise defined.
Bulkhead deck
means the uppermost deck to which transverse watertight bulkheads and the watertight shell extend.
Coast Guard District Commander or District Commander
means an officer of the Coast Guard designated by the Commandant to command activities of the Coast Guard within a Coast Guard district described by 33 CFR part 3, whose duties include the inspection, enforcement, and administration of laws for the safety and navigation of vessels.
Coastwise
refers to a route not more than 20 nautical miles offshore on any of the following waters:
(1) Any ocean.
(2) The Gulf of America.
(3) The Caribbean Sea.
(4) The Gulf of Alaska.
(5) The Bering Sea.
(6) Such other, similar waters as may be designated by the District Commander.
Combustible liquid
means the same as in subpart 30.10 of this chapter.
Commandant
means the Commandant of the Coast Guard or an authorized staff officer at Coast Guard headquarters designated by § 1.01-05 of this chapter.
Commanding Officer, Marine Safety Center,
means an officer of the Coast Guard designated by the Commandant to command activities of the Coast Guard within the Marine Safety Center, whose duties include review of plans for commercial vessels to ensure compliance with applicable laws and standards.
Crane
means a revolving, gantry-mounted, or other type of fixed lifting device used for lifting or moving equipment or supplies. It does not include material handling equipment used for general ship's service, such as lifeboat davits, chain falls, come-alongs, or the like.
Credential
means any or all of the following:
(1) Merchant mariner's document.
(2) Merchant mariner's license.
(3) STCW endorsement.
(4) Certificate of registry.
(5) Merchant mariner credential.
Crew
means all persons carried on board the OSV to provide navigation and maintenance of the OSV, its machinery, systems, and arrangements essential for propulsion and safe navigation or to provide services for other persons on board.
Deadweight
means, when measured in water of specific gravity 1.025, the difference in long tons between—
(1) The displacement of the vessel on even trim at “lightweight” as defined by subpart F of part 170 of this chapter; and
(2) The displacement of the vessel on even trim at the deepest load waterline.
Embarkation ladder
means the ladder provided at survival craft embarkation stations to permit safe access to survival craft after launching.
Embarkation station
means the place where a survival craft is boarded.
Existing offshore supply vessel
is one contracted for, or the keel of which was laid, before March 15, 1996.
Flammable liquid
means the same as in § 30.10-22 of this chapter.
Float-free launching
means that method of launching a survival craft or lifesaving appliance whereby the craft or appliance is automatically released from a sinking vessel and is ready for use.
Gas-free
means free from dangerous concentrations of flammable or toxic gases.
Gross register tons
or
GRT
means the gross ton measurement of the vessel under the Regulatory Measurement System described in 46 U.S.C. 14502.
Gross tonnage ITC
or
GT ITC
means the gross tonnage measurement of the vessel under the Convention Measurement System described in 46 U.S.C. 14302.
Hazardous material
means the same as in § 153.2 of this chapter.
Immersion suit
means a protective suit that reduces loss of body heat of a person wearing it in cold water.
Inflatable appliance
means an appliance that depends upon nonrigid, gas-filled chambers for buoyancy and that is normally kept uninflated until ready for use.
Inflated appliance
means an appliance that depends upon nonrigid, gas-filled chambers for buoyancy and that is kept inflated and ready for use at all times.
International voyage
means a voyage between a country to which the International Convention for the Safety of Life at Sea, 1974, as amended (SOLAS 74/83) applies and a port outside that country.
Jacking system
means any type of mechanical (including hydraulic) or electrical system used for elevating a liftboat.
Launching appliance
or
launching arrangement
means the method or devices for transferring a survival craft or rescue boat from its stowed position to the water. For a launching arrangement using a davit, the term includes the davit, winch, and falls.
Length,
relative to a vessel, means the length listed on the vessel's certificate of documentation or the “registered length” as defined by § 69.53 of this chapter.
Lifejacket
means a flotation device approved as a life preserver or lifejacket.
Liftboat
means an OSV with movable legs capable of raising its hull above the surface of the sea.
Major conversion
means a conversion of a vessel that, as determined by the Commandant—
(1) Substantially changes the dimensions or carrying capacity of the vessel;
(2) Changes the type of vessel;
(3) Substantially prolongs the life of the vessel; or
(4) Otherwise so changes the vessel that it is essentially a new vessel.
Marine evacuation system
means an appliance designed to rapidly transfer large numbers of persons from an embarkation station by means of a passage to a floating platform for subsequent embarkation into associated survival craft, or directly into associated survival craft.
Marine inspector
means any person authorized by the Officer in Charge, Marine Inspection (OCMI), to perform duties concerning the inspection, enforcement, and administration of laws for the safety and navigation of vessels.
Muster station
means the place where the crew and offshore workers assemble before boarding a survival craft.
New offshore supply vessel
is one—
(1) Contracted for, or the keel of which was laid, on or after March 15, 1996; or
(2) Which underwent a major conversion that was initiated on or after March 15, 1996.
Novel lifesaving appliance or arrangement
means one that has new features not fully covered by the provisions of this part but that provides an equal or higher standard of safety.
Noxious liquid substance
or
NLS
means the same as in § 153.2 of this chapter.
Ocean
refers to a route more than 20 nautical miles offshore on any of the following waters:
(1) Any ocean.
(2) The Gulf of America.
(3) The Caribbean Sea.
(4) The Gulf of Alaska.
(5) The Bering Sea.
(6) Such other, similar waters as may be designated by the District Commander.
OCMI
means the same as Officer in Charge, Marine Inspection.
Officer in Charge, Marine Inspection
means any person of the Coast Guard so designated by the Commandant, to be in charge of an inspection zone for the performance of duties concerning the inspection, enforcement, and administration of laws for the safety and navigation of vessels.
Offshore supply vessel
or
OSV
means a vessel that—
(1) Is propelled by machinery other than steam;
(2) Does not meet the definition of a passenger-carrying vessel in 46 U.S.C. 2101(22) or 46 U.S.C. 2101(35);
(3) Is more than 15 gross tons; and
(4) Regularly carries goods, supplies, individuals in addition to the crew, or equipment in support of exploration, exploitation, or production of offshore mineral or energy resources.
Offshore worker
means an individual carried aboard an OSV and employed in a phase of exploration, exploitation, or production of offshore mineral or energy resources served by the vessel; but it does not include the master or a member of the crew engaged in the business of the vessel, who has contributed no consideration for carriage aboard and is paid for services aboard.
Quarters
means any space where sleeping accommodations are provided.
Rescue boat
means a boat designed to rescue persons in distress and to marshal survival craft.
Restricted service
means service in areas within 12 hours of a harbor of safe refuge or in areas where a liftboat may be jacked up to meet the 100-knot-wind severe-storm criteria of § 174.255(c) of this chapter.
Seagoing condition
means the operating condition of the OSV with the personnel, equipment, fluids, and ballast necessary for safe operation on the waters where the OSV operates.
Survival craft
means a craft capable of sustaining the lives of persons in distress from the time of abandoning the OSV on which the persons were originally carried. The term includes lifeboats, liferafts, buoyant apparatus, and lifefloats, but does not include rescue boats.
Underwater survey
means the examination of the vessel's underwater hull including all through-hull fittings and appurtenances, while the vessel is afloat.
[CGD 82-004 and CGD 86-074, 62 FR 49321, Sept. 19, 1997, as amended by USCG-1999-4976, 65 FR 6505, Feb. 9, 2000; USCG-2000-6858, 67 FR 21082, Apr. 29, 2002; USCG-2007-29018, 72 FR 53966, Sept. 21, 2007; USCG-2006-24371, 74 FR 11266, Mar. 16, 2009; USCG-2012-0208, 79 FR 48934, Aug. 18, 2014; USCG-2015-0867, 80 FR 62469, Oct. 16, 2015]
- Cross-references to the US Code
- 46:14302.46:14502.46:2101
- Cross-references to the CFR
- 1.01-05153.2174.25530.10-2269.53