Maritime Industry Acronyms

The IMO is the United Nations specialized agency responsible for regulating international shipping. Founded in 1948, it develops and maintains a comprehensive regulatory framework for shipping, covering safety, environmental concerns, legal matters, technical cooperation, and security. The IMO sets standards ranging from safety and pollution standards to maritime security and shipping efficiency requirements.

SOLAS is the most important international treaty concerning the safety of merchant ships. First adopted in 1914 after the Titanic disaster, it prescribes minimum standards for the construction, equipment, and operation of ships to ensure their safety. SOLAS sets minimum safety standards in the construction, equipment, and operation of ships, safeguarding life onboard.

MARPOL is the main international convention covering prevention of pollution of the marine environment by ships. It addresses pollution by oil, chemicals, sewage, garbage, and air emissions through six technical annexes. MARPOL is considered one of the most important international maritime conventions relating to operational and environmental pollution standards for vessels.

STCW establishes qualification standards for masters, officers, and watch personnel on seagoing merchant ships. It ensures that seafarers worldwide meet minimum training, certification, and watchkeeping requirements for safe vessel operation. STCW sets minimum qualifications for crew members on board vessels.

IALA is a non-profit organization that harmonizes aids to navigation worldwide and works to improve the safety and efficiency of navigation. It develops technical standards for VTS, AIS, buoyage systems, and other navigational aids.

COLREGS, formally known as the Convention on the International Regulations for Preventing Collisions at Sea (1972), establishes the 'rules of the road' for vessels at sea. It covers navigation lights, sound signals, steering rules, and conduct in various visibility conditions.

The ISM Code provides an international standard for the safe management and operation of ships. It requires shipping companies to develop, implement, and maintain a Safety Management System (SMS) with objectives for safety and environmental protection.

ISPS Code was developed in response to threats to ships and port facilities following 9/11. It prescribes security responsibilities for governments, shipping companies, ship personnel, and port facility personnel to detect and deter security threats.

The ILO is a UN agency and global organization that sets international labour standards, including those for seafarers' working conditions. It developed the Maritime Labour Convention which consolidates nearly all existing international maritime labour standards, promoting decent working conditions for all.

The MLC 2006 is an international labour convention ensuring comprehensive rights and protection at work for seafarers worldwide. It covers minimum working age, employment agreements, hours of work, wages, accommodation, food, health protection, and social security. The MLC sets out minimum standards and rights to decent conditions of work for seafarers employed on ships.

ICS is a trade association for the shipping industry that advises intergovernmental agencies on all regulatory, legal, and operational issues and international policies within the shipping industry.

SIGTTO is a non-profit organization that addresses concerns, shares best practice and experience, and develops policy for improvement in maritime operations of companies involved in the transportation of liquefied natural gas (LNG) and liquefied petroleum gas (LPG).

OCIMF is recognized as the voice of the oil industry, providing expertise and guidance on shipping safety and environmental protection. It develops industry standards and best practices for tanker operations.

INTERTANKO is a trade association representing the interests of independent tanker owners at industry forums. INTERTANKO also supports industry bodies in developing policies for the tanker shipping industry.

INTERCARGO represents the interests of dry cargo shipowners and promotes safety and environmental protection across the industry.

CDI is an organization with an inspection and audit scheme for the global transportation and storage of bulk and packaged chemicals, ensuring safety and quality standards throughout the supply chain.

IACS is a non-governmental organization made up of 12 marine classification societies members. Classification standards are set by the member societies of IACS. They define and maintain construction and operation standards for ships and offshore structures.

ISO is a global organization that sets international standards based on expertise and consensus-based studies, covering various aspects of maritime operations and safety.

The MCA is responsible for implementing British and international maritime law and safety policy in the United Kingdom.

IAPH is the global trade association for ports and port related businesses worldwide, promoting cooperation and development in port operations.

The USCG performs the duties of port state control across America, in addition to other roles including search and rescue, maritime law enforcement, and aids to navigation.

PSC is a regime that oversees the inspection of foreign-registered ships when calling at ports that are not under the jurisdiction of its flag state or fellow MoU members, to verify that the condition of the ship, its equipment, crew and operation comply with international regulations. PSC officers can inspect certificates, equipment, and vessel conditions, and may detain non-compliant vessels until deficiencies are rectified.

VTS is a marine traffic monitoring system designed to improve safety and efficiency of navigation, protect the environment, and assist in search and rescue operations. VTS operators monitor vessel movements, provide navigational information, and coordinate traffic flow in designated areas.

A VTSO is a qualified professional who operates VTS equipment and communicates with vessels in the VTS area. They monitor traffic, provide information services, navigational assistance, and traffic organization services to ensure safe and efficient vessel movements.

VHF radio (156-174 MHz) is the primary means of voice communication for maritime operations. Channel 16 (156.8 MHz) is the international distress, safety, and calling frequency. VHF is used for ship-to-ship, ship-to-shore, and VTS communications.

SMCP is a set of standardized English phrases developed by IMO for maritime communication. It ensures clear, concise, and unambiguous radio communications between ships and shore stations, reducing the risk of misunderstandings that could lead to accidents.

AIS is an automatic tracking system that uses VHF radio to exchange data between ships and shore stations. It broadcasts vessel identity, position, course, speed, and other safety-related information, significantly enhancing situational awareness and collision avoidance. AIS uses transponders on ships to identify a ship's location.

Marine radar is essential navigation equipment that uses radio waves to detect other vessels, land, and navigational hazards. It's crucial for safe navigation in restricted visibility and for collision avoidance, working alongside AIS and visual observation.

ARPA is a computerized radar system that automatically tracks targets and calculates their course, speed, CPA, and TCPA. It assists navigators in collision avoidance by providing continuous tracking of multiple targets and predicting potential collision situations.

ECDIS is a computer-based navigation system that displays electronic navigational charts and integrates position information from GPS, radar, AIS, and other sensors. When properly maintained with official ENCs, it can replace paper charts as the primary navigation system.

ENCs are vector-based digital charts produced by or under the authority of national hydrographic offices. They conform to IHO S-57 standards and contain all chart information necessary for safe navigation. Official ENCs are required for ECDIS to meet carriage requirements.

CCTV systems in VTS centers provide visual monitoring of critical areas such as harbor entrances, narrow channels, locks, and bridges. They complement radar and AIS data, helping VTS operators verify vessel movements and monitor compliance with traffic regulations.

GPS is a satellite-based navigation system operated by the United States that provides precise positioning, navigation, and timing services worldwide. It's a fundamental tool for maritime navigation, used by virtually all vessels for position fixing and navigation.

GNSS is the generic term for satellite navigation systems that provide global coverage. This includes GPS (USA), GLONASS (Russia), Galileo (EU), and BeiDou (China). Modern marine receivers often use multiple GNSS for improved accuracy and reliability.

DGPS improves GPS accuracy by using ground-based reference stations to broadcast correction data. It can provide positioning accuracy within 1-3 meters, compared to standard GPS accuracy of 5-10 meters, making it valuable for precision navigation in restricted waters.

ETA is the predicted time a vessel will arrive at a destination or specific point. It's calculated based on current position, speed, distance to destination, and expected conditions. ETAs are regularly communicated to ports, VTS, and other stakeholders.

ETD is the predicted time a vessel will depart from a port or anchorage. It's used for planning purposes by port authorities, pilots, tugs, and other service providers to coordinate resources and schedule operations efficiently.

CPA is the minimum distance that will occur between two vessels if they maintain their current courses and speeds. It's a critical parameter in collision avoidance, automatically calculated by ARPA systems and used to assess collision risk.

TCPA is the time remaining until two vessels reach their CPA. Combined with CPA distance, TCPA helps navigators determine if a collision risk exists and how much time is available to take avoiding action if necessary.

COG is the actual direction of vessel movement relative to the earth's surface, typically provided by GPS. It differs from the vessel's heading when affected by current or leeway, representing the vessel's track made good through the water.

SOG is the vessel's actual speed relative to the earth's surface, typically measured by GPS. It represents the vessel's speed made good and accounts for the effects of current, differing from speed through water when current is present.

STW is the vessel's speed relative to the surrounding water, typically measured by a log. It differs from SOG when current is present, as STW doesn't account for water movement relative to the seabed.

RoT indicates how quickly a vessel is changing its heading, typically measured in degrees per minute. It's displayed on navigation equipment and transmitted via AIS, helping other vessels anticipate the turning vessel's future position.

GMDSS is an internationally agreed set of safety procedures, equipment, and communication protocols to increase safety and make it easier to rescue distressed ships, boats and aircraft. It uses satellite and terrestrial radio services to ensure rapid alerting of shore-based rescue coordination centers.

EPIRB is a distress beacon that, when activated, transmits a signal via satellite to rescue coordination centers. Modern 406 MHz EPIRBs include GPS positioning and unique identification, enabling rapid and accurate location of vessels in distress.

SART is a portable device that, when activated, responds to 9 GHz radar signals and produces a distinctive pattern on the radar screen of searching vessels or aircraft. This helps rescuers locate survival craft or persons in distress.

SAR refers to the organized effort to locate and assist persons in distress or immediate danger. The IMO SAR Convention establishes an international SAR plan with defined search and rescue regions, coordination centers, and procedures.

DSC is a semi-automated method of establishing radio contact using digital codes. It's part of GMDSS and allows rapid transmission of distress alerts with vessel identity and position, automatic acknowledgment, and selective calling of individual stations.

MMSI is a unique nine-digit number used to identify ships, coast stations, and groups of ships in maritime radio communications, including DSC, AIS, and satellite communications. It's essential for GMDSS and modern maritime communication systems. MMSIs are used by automatic identification systems (AIS) to uniquely identify a ship.

MOB is an emergency situation where a person falls into the water from a vessel. Modern navigation systems have MOB functions that mark the position and provide guidance for recovery. Immediate action and proper procedures are critical for successful recovery.

LSA refers to equipment required by SOLAS for emergency situations, including lifeboats, life rafts, life jackets, immersion suits, and associated equipment. Regular maintenance, inspection, and crew training in LSA use are mandatory requirements.

FFA encompasses all fire detection, prevention, control, and extinguishing equipment required on ships. This includes fire detection systems, extinguishers, fixed firefighting systems, fireman's outfits, and breathing apparatus. Regular drills and maintenance are mandatory.

DWT is the weight of cargo, fuel, fresh water, stores, passengers and crew that a vessel can carry when loaded to its maximum summer load line. It's a key measure of a ship's carrying capacity and economic earning potential. DWT defines the weight a vessel can carry and is used in technical vessel documents and classifications.

GRT is a ship's total internal volume expressed in register tons. Though largely replaced by GT (Gross Tonnage) under the 1969 Tonnage Convention, GRT is still referenced in older vessels and some regulations.

NRT represents the earning capacity of a ship, calculated by subtracting space occupied by accommodation, machinery, and navigation equipment from GRT. It's used to calculate port dues, canal tolls, and other fees in some jurisdictions.

TEU is a standard unit for describing container ship capacity or cargo volume. One TEU represents the capacity of a standard 20-foot shipping container (20 feet long × 8 feet wide × 8.5 feet high).

FEU represents the capacity of a standard 40-foot shipping container. One FEU equals two TEUs. Container vessels and terminals often specify capacity in both TEU and FEU to accommodate different container sizes.

B/L is a legal document issued by a carrier to a shipper acknowledging receipt of cargo for shipment. It serves as a contract of carriage, a receipt for goods, and a document of title that can be bought, sold, or traded while goods are in transit.

LOA is the maximum length of a vessel's hull measured parallel to the waterline. It's a critical dimension for determining whether a vessel can fit in docks, locks, and berths, and is used in port tariff calculations.

LBP is the length of a ship measured between perpendiculars drawn at the forward and aft extremities of the waterline. It's used in ship design calculations and certain regulatory requirements.

SWL is the maximum load that lifting equipment (cranes, derricks, slings) is designed to handle safely under normal working conditions. It includes a safety factor and must never be exceeded to prevent equipment failure and accidents.

BHP is the actual power output of an engine at its shaft before losses from transmission and auxiliaries. It's a key specification for ship's engines and is used to calculate vessel performance and fuel consumption.

RPM measures the rotational speed of the ship's engine or propeller shaft. Engine RPM directly affects vessel speed and fuel consumption. Modern engines often have optimal RPM ranges for efficiency.

STS transfer refers to the transfer of oil or gas cargo between two vessels positioned alongside each other, typically performed at sea or in designated areas.

VLCC is a tanker class typically ranging from 200,000 to 320,000 DWT. These vessels transport large quantities of crude oil on long-haul routes and are too large for most ports, often loading and discharging at offshore terminals. VLCCs can carry in excess of 250,000 Dead Weight Tonnage.

ULCC represents the largest tankers, over 320,000 DWT. Due to their enormous size, draft, and limited port accessibility, few ULCCs remain in service. The largest ever built exceeded 550,000 DWT. ULCCs are among the largest tankers used to transport crude oil products.

Classed based on physical dimensions and DWT, Long Range 1 (LR1) and Long Range 2 (LR2) tankers are large tankers designed to transport refined and crude cargoes long distances.

Classed based on physical dimensions and DWT, Medium Range 1 (MR1) and Medium Range 2 (MR2) tankers are medium sized tankers designed to transport refined cargo long distances.

LNG carriers are specialized vessels designed to transport natural gas cooled to -162°C in liquid form. They feature sophisticated insulated containment systems and represent one of the most complex and expensive vessel types.

LPG carriers transport propane, butane, and other petroleum gases in liquefied form under pressure or refrigeration. They range from small coastal vessels to large seagoing carriers and require specialized safety systems.

Ro-Ro vessels feature built-in ramps allowing vehicles to drive on and off. They carry cars, trucks, trailers, and rolling equipment. Pure Car Carriers (PCC) and Pure Car and Truck Carriers (PCTC) are specialized Ro-Ro types. RoRo ships are ferries on which cars or similar vehicles can be driven on and off.

PCTC is a specialized Ro-Ro vessel designed exclusively for transporting automobiles and light trucks. They feature multiple decks with adjustable heights and can carry thousands of vehicles on a single voyage.

OBO vessels are designed to carry ore, bulk cargo, or oil, providing operational flexibility. They can switch between cargo types depending on market conditions, though their complexity and maintenance costs have reduced their popularity.

FPSO is a floating vessel used in offshore oil and gas industry to process, store, and offload hydrocarbons. Often converted tankers, FPSOs enable production from remote offshore fields without pipeline infrastructure.

OSV provides supplies, equipment, and personnel to offshore oil and gas platforms. They're designed for excellent station-keeping in rough seas and often feature dynamic positioning systems for safe operation near platforms.

PSV is a specific type of OSV designed to transport supplies like drilling fluids, cement, and equipment to offshore platforms. They typically have large cargo decks and specialized cargo handling systems.

MODUs are floating drilling units such as semi-submersibles and jack-up rigs used for offshore oil and gas exploration and production.

CoC is issued to seafarers who meet STCW standards for specific ranks and positions. It certifies that the holder has the required training, qualifications, and sea service to perform duties at their designated rank.

CoR is the document that proves a ship's nationality and ownership. It's issued by the flag state and must be carried on board at all times. It includes details about the vessel, owners, and registration.

SMC is issued to ships that comply with the ISM Code requirements. It certifies that the ship's safety management system has been audited and meets international standards for safe operation and pollution prevention.

DoC is issued to shipping companies demonstrating compliance with ISM Code requirements. It certifies that the company's shore-based safety management system meets international standards and can effectively manage its vessels.

IOPP certificate verifies that a ship complies with MARPOL Annex I requirements for oil pollution prevention. It covers equipment like oily water separators, oil discharge monitoring systems, and proper documentation procedures.

ISSC certifies that a ship complies with ISPS Code security requirements. It's issued after verification that the ship has a valid Ship Security Plan and meets all security-related requirements of the ISPS Code.

CSR is a permanent record of a ship's history required by SOLAS. It includes information about the ship's name, state of registry, date of registry, identification number, port of registry, and name of registered owners.

A Vessel IMO Number consists of seven digits and begins with the letters "IMO". Once assigned, the number remains unchanged. IMO numbers were introduced to improve maritime safety, security and to reduce maritime fraud.

ECA is a designated sea area where stricter controls on emissions apply to reduce air pollution from ships. These areas have specific limits for sulfur oxides, nitrogen oxides, and particulate matter from ship exhausts.

SECA is an emission control area specifically for sulfur emissions. In SECAs, ships must use fuel with maximum 0.10% sulfur content or use equivalent emission reduction methods like scrubbers.

BWM refers to the treatment and management of ballast water to prevent transfer of invasive aquatic species between ecosystems. The BWM Convention requires ships to treat ballast water using approved systems before discharge.

SOPEP is a mandatory plan required under MARPOL for all oil tankers and ships over 400 GT. It provides procedures and organizational structure for responding to oil pollution incidents, including notification procedures and response actions.

EEDI is a mandatory measure for new ships that establishes minimum energy efficiency requirements. It compares the CO2 emissions of a ship to a reference line, promoting more fuel-efficient vessel designs and reducing greenhouse gas emissions. EEDI is an IMO technical measure and standard for vessel energy efficiency design, regularly updated to stay abreast of technology advances.

SEEMP is a ship-specific plan establishing a mechanism to improve the energy efficiency of ship operations. It includes monitoring of fuel consumption and CO2 emissions, and planning operational measures to improve efficiency.

GHG refers to gases that trap heat in the atmosphere, primarily CO2, methane, and nitrous oxide from maritime operations. IMO has adopted strategies to reduce GHG emissions from international shipping and move toward decarbonization.

HNS refers to substances that create risks to human health or the marine environment when transported by sea. The HNS Convention provides compensation framework for damage caused by incidents involving HNS cargo.

SIRE is an OCIMF inspection programme for vessels involved in transporting oil, gas, and hazardous chemicals. SIRE is comprised of accredited inspectors who inspect tankers and barges, after which the inspection reports are made available to others in the industry, such as charterers and oil companies.

OVID is an OCIMF inspection programme for the offshore oil and gas industry. OVID is comprised of accredited inspectors who inspect offshore vessels, after which the inspection reports are made available to others in the industry, such as charterers and oil companies.

MTIS is an OCIMF programme providing a centralized storage of terminal and berth data. MTIS is a free-to-access database which supports the successful matching of ships and berths.

TMSA is an OCIMF management self-assessment programme that supports the SIRE Programme, setting industry standards and providing companies with a means to improve and measure their own safety management systems for tankers.

OVMSA is an OCIMF management self-assessment programme that supports the OVID Programme, providing offshore vessel operators with a framework to improve and measure their safety management systems.

MTMSA is an OCIMF management self-assessment programme that supports the MTIS Programme, helping marine terminals improve and measure their safety management systems.

ISGOTT provides guidance and recommendations on the handling and safe carriage of crude oil and petroleum for tankers and terminals, representing industry best practice.

EBIS is an inspection scheme with the goal of improving standards in barge shipping across Europe.

A nautical mile is a term of measurement equal to approximately 1,852 meters (6,076 feet). It's based on the circumference of the Earth and is the standard unit of distance used in maritime and aviation navigation.

The bow is the front or forward-most part of a vessel, designed to cut through water and reduce resistance as the vessel moves forward.

The stern is the rear or aft-most part of a vessel, where the rudder and propulsion systems are typically located.

Aft refers to the back half of the vessel or movement toward the stern. "Going aft" means moving toward the rear of the ship.

Astern describes a vessel moving in reverse, with the stern leading. "Full astern" is a command to reverse the engines at maximum power.

Port is the left-hand side of a vessel when looking forward toward the bow. Port is indicated by red navigation lights at night.

Starboard is the right-hand side of a vessel when looking forward toward the bow. Starboard is indicated by green navigation lights at night.

A berth is a ship's allotted place to dock at a port or terminal, providing access to shore-side facilities for loading, unloading, and vessel services.

Flag State is the country where a vessel is registered. Flag States also stipulate the laws under which the vessel and its crew are governed when operating in that jurisdiction and international waters.

Port State is the country a vessel enters. When in Port State waters, a vessel must comply with the laws of the Port State.

FOC is a business practice whereby a ship is registered under the registry of a country different to that of its owners. This practice is often held in a negative regard as a ship may be registered in a foreign country to avoid the regulations of the owners' country which may have stricter standards.

MoU is a formal agreement between two or more parties outlining terms and details of an understanding, including responsibilities and requirements.

Classification societies are non-governmental organisations that define and maintain construction and operation standards for ships and offshore structures. They certify that vessels meet specific safety and quality standards.

A vessel must be designed, built and maintained as per the rules of its classification society and approved by its flag state. When a vessel meets these requirements, a Class Certificate is issued.

The supply chain is the sequence of processes and players involved in the production and distribution of a commodity from start to finish, including maritime transportation.

Dark activity is a period of time in which a vessel fails to transmit an AIS signal and cannot be identified or located, which may indicate intentional signal disabling or equipment malfunction.