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An oil/bulk/ore carrier, a combination ship able to carry either oil or dry bulk cargoes, giving flexibility between trades.

The sea areas (designated A1 to A4 by radio coverage) used to define the radio equipment a ship must carry under the GMDSS. IMO-grounded

A proprietary onboard decision-support system providing motion and loading information to assist safe operation.

A certificated member of the ship's company holding a position of responsibility in the deck, engine, or other department, qualified under the STCW Convention. IMO-grounded

The officer in charge of the navigational or engineering watch, responsible for the safe conduct of the ship during that period. IMO-grounded

A table of measurements (offsets) defining the shape of the hull at each station and waterline, used to lay off and build the form.

The coordinates that define points on the hull surface, taken from the lines plan and listed in the offset table.

Relating to activities and structures at sea away from the coast, such as oil and gas exploration, production, and support.

Heavy-duty cranes on offshore vessels and platforms, designed to work safely with the relative motion between vessel and load in a seaway.

Offshore cranes used to handle cargo and equipment on a vessel's own deck, as distinct from lifts to and from other vessels.

Cranes on supply vessels used to transfer cargo and equipment to and from offshore installations.

A floating or fixed structure used for offshore activities such as drilling, production, accommodation, or support.

Petroleum in any form, including crude oil and refined products; its carriage and the prevention of oil pollution are governed by MARPOL Annex I. IMO-grounded

The collection and removal of spilled oil from the water surface, using skimmers, booms, and recovery vessels.

An association of oil companies that promotes safe and environmentally responsible operation of tankers and terminals, issuing widely used guidance.

A shaft arrangement through which lubricating oil is distributed to the components of a machine.

United States legislation enacted after a major tanker spill, imposing stringent requirements on tankers and liability for oil pollution in US waters.

The official log, required under MARPOL Annex I, in which all oil transfers, discharges, and disposals are recorded for inspection by authorities. IMO-grounded

The shipboard system that collects oily residues and treats sludge for proper disposal in accordance with MARPOL Annex I. IMO-grounded

A film or layer of oil spread on the water surface, the visible sign of an oil spill.

A vessel equipped to respond to oil spills, carrying booms, skimmers, and storage for recovered oil.

A ship constructed to carry oil in bulk in its cargo spaces, subject to MARPOL Annex I requirements such as double hulls, segregated ballast, and oil-discharge monitoring. IMO-grounded

The cleaning of oil, for example fuel or lubricating oil, by settling, heating, and centrifuging to remove water and solids.

A combination carrier designed to carry oil, dry bulk, or ore cargoes, allowing it to switch between wet and dry trades.

An instrument that detects the boundary between oil and water in a tank, used to control discharge and avoid pumping oil overboard. IMO-grounded

A mixture containing oil, such as oily bilge or ballast water, the discharge of which is controlled under MARPOL Annex I. IMO-grounded

Rags soaked with oil, which present a fire risk through spontaneous combustion and are disposed of as oily waste.

Equipment that separates oil from bilge or ballast water so that the water may be discharged within the 15 ppm limit set by MARPOL Annex I. IMO-grounded

Surveys of a ship's condition and bunkers carried out at the start and end of a charter to record its state and fuel quantities.

Lifeboat release hooks that can release the boat while it is still under load (waterborne or suspended); their safe design has been the subject of IMO measures to prevent accidental release. IMO-grounded

A person designated to coordinate search-and-rescue operations at the scene, following the IAMSAR procedures. IMO-grounded

A diving bell open at the bottom, used to transport divers to and from a worksite at depth without maintaining internal pressure above the surrounding water.

Ships designed to carry cargo on open decks, such as certain heavy-lift and project-cargo vessels.

A means of measuring a tank's contents that involves an opening to the atmosphere, permitted only for cargoes that do not present a vapour hazard. IMO-grounded

Ro-ro cargo spaces open at both ends, or at one end, with adequate natural ventilation throughout, which affects their fire-safety and ventilation requirements under SOLAS. IMO-grounded

Waters away from the coast and confined channels, where a vessel has sea room to manoeuvre.

A cargo-tank venting arrangement that is open to the atmosphere through devices such as flame screens, permitted for certain cargoes, as opposed to a controlled (closed) system. IMO-grounded

Vehicle spaces open at both ends or with adequate openings for natural ventilation, which determines their fire-safety treatment under SOLAS. IMO-grounded

The efficiency of a propeller operating in undisturbed water, used as a reference in propulsion analysis.

Control systems that act on a set input without using feedback of the result, as opposed to closed-loop control.

Holes in the hull, decks, and bulkheads, such as hatches, doors, and ports, whose means of closure must maintain watertight and weathertight integrity under the Load Line Convention and SOLAS. IMO-grounded

The measured parameters that show how an engine is performing, such as pressures, temperatures, and speeds, monitored to ensure safe operation.

A manual giving instructions for the safe and correct operation of equipment or systems aboard.

Describing the state of being in service and functioning, or matters relating to a ship's day-to-day running.

Design that takes account of how the ship and its systems will be operated and maintained in service.

The company or person responsible for operating a ship, or a crew member who operates a particular machine or system.

A ship designed to carry dense ore cargoes, with high-positioned holds and strong structure to suit the heavy, concentrated loads.

A combination carrier able to carry either ore or oil cargoes.

A proprietary fuel consisting of bitumen emulsified in water, formerly used as a boiler fuel and carried as a cargo.

The movement of a solvent through a semipermeable membrane; reverse osmosis, driven by pressure, is used aboard to produce fresh water from seawater.

Toward or beyond the ship's side, away from the centreline; the opposite of inboard.

A survey intended to report on the overall condition of the hull structure and to determine the extent of any close-up survey, part of the periodic survey programme. IMO-grounded

The escape of liquid from a tank that has been filled beyond its capacity, controlled by overflow arrangements to prevent spillage.

Pipes that carry away liquid from a tank when it is full, leading it safely to an overflow tank or other location.

A welding position in which the weld is made on the underside of the joint, with the welder working upward against gravity, the most difficult position.

A load greater than the safe design value, which can cause damage or failure if not prevented by protection.

A device or system that protects equipment, such as a motor or generator, from damage by disconnecting or limiting it when an overload occurs.

A means of manually taking control of, or bypassing, an automatic function, used in particular circumstances.

A device that shuts down or limits an engine or turbine if its speed rises dangerously above the rated value, preventing damage.

The gas essential for combustion and respiration; controlling its concentration is central to making tanks inert and safe for entry. IMO-grounded

An instrument that measures the oxygen concentration in an atmosphere, used to verify that tanks are inert or that spaces are safe to enter.

A cutting process that uses a jet of oxygen to burn through preheated steel, widely used for cutting plate.

A process using an oxygen jet to gouge a groove in steel, for example to remove a defect or to back-gouge a weld.

Chemicals such as halons and CFCs that damage the ozone layer; their use aboard ship is controlled and being phased out under MARPOL Annex VI and the Montreal Protocol. IMO-grounded

A measure of how much a substance can deplete the ozone layer relative to a reference chemical, used in regulating refrigerants and fire-extinguishing agents. IMO-grounded