Following is a glossary of terms related to underwater ship hulls, in alphabetical order


To attract and bind (molecules of a substance in a fluid) so as to form a thin layer on the surface, by non-electrostatic forces; to bind by adsorption. Distinguished from absorb, in which the foreign substance penetrates the body of the absorbing material.

AF paints

Antifouling paints, paints which have in them toxic substances designed to kill the fouling before it attaches to the ship’s hull or after it has attached.


Ecology An organism, especially a plant or animal, that occurs in or is naturalized in a region to which it is not native.


A chemical agent, such as a pesticide, that is capable of destroying living organisms.

Bunker fuel

As used on this website, bunker fuel is technically any type of fuel oil used aboard ships. It gets its name from the tanks in ships and in ports that it is stored in, called bunkers


Literally means composed or containing calcium carbonate or lime. In the case of calcareous fouling, the word is used to refer to animals or organisms with a hard shell, such as barnacles.


Chemistry. A pure, macroscopically homogeneous substance consisting of atoms or ions of two or more different elements, in definite proportions, that cannot be separated by physical means. A compound usually has properties unlike those of its constituent elements.


To introduce impurities or foreign matter.


Any of various small predominantly aquatic animals, including lobsters, crabs, shrimps, and barnacles.


Copper (chemical symbol Cu)


Ecospeed ship hull performance technology is the combination of a patented advanced coating and an underwater maintenance system. Ecospeed’s impermeable coating prevents corrosion and pitting and provides exceptional resistance to mechanical damage. The underwater hull cleaning maintenance system produces Ecospeed’s smooth surface and retains its integrity throughout. Unlike traditional marine paints which deteriorate over time, Ecospeed lasts the lifetime of the vessel, is guaranteed for 10 years, and will never require full repainting. The coating actually improves in performance over the lifetime of the hull if it is standardly applied and maintained. Ecospeed is guaranteed for 10 years. The Ecospeed coating is 100% free of biocides and is environmentally safe. It gets smoother with each cleaning which reduces friction and also makes it harder for marine fouling to attach.

Entrainment: entrain

The drawing of solid particles, air bubbles, or liquid drops into a moving fluid and carrying of them along in the flow.

Environmental impact

The indirect and direct consequences of human actions on the natural environment. In the case of shipping, these include harmful gases and particles emitted into the air, and poisonous or toxic substances being spread in the water. There is also a concern that marine species transported from their natural environment to another location where they are not native can have adverse effects on the environment they invade. These are known as Non-indigenous Marine Species (NIMS or NIS) or “alien” species and can be transported by ships in their ballast water or as fouling on a badly fouled hull.

Episodic pulse

Discharges occurring in isolated incidents or occasionally.


An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea.


Related to an estuary, which is that part of the mouth or lower course of a river where it approaches and meets the sea.


In the US Navy, a warship larger than a destroyer and smaller than a cruiser

Green Ship certification

This is a certificate given to ships that are extra clean and safe (in terms of quality, safety and environmental friendliness). With this certificate, ships will benefit from reduced port fees. For the owner it means recognition as well as financial benefits.

Hazard assessment

Risk analysis.


Chemical substances used to destroy or inhibit the growth of plants, especially weeds. Herbicides are used in antifouling paints.

Hull performance

The degree to which a ship’s hull moves smoothly and easily through the water or resists motion through the water, which depends on what condition the ship’s hull is in. The hull performance is dependent on the shape of the hull, the condition of the hull itself, the coating used on the hull and also on the nature and extent of fouling on the hull (e.g. slime has been observed to cause an increase in power required to maintain speed of 6 - 12% compared to a hydraulically smooth hull, weed to cause an increase of 20%, and heavy shell fouling to cause as much as a 53% increase, all on a certain type of ship at a given speed). More growth means more resistance and thus higher fuel consumption which in turn results in more atmospheric pollution. When we talk about improving hull performance we are referring to taking those measures needed to make sure a ship’s hull is as smooth and friction-free as possible for any sailing the ship does. The best approach we have found is the standard application of a hard coating combined with routine, thorough, in-water cleaning, such as is contained in our Ecospeed system.


Is a general term for the study and application of sound in water.


In the same place. Used in footnotes and bibliographies to refer to the book, chapter, article, or page cited just before.


The International Maritime Organization: A specialized agency of the United Nations that is responsible for measures to improve the safety and security of international shipping and to prevent marine pollution from ships. The IMO’s objectives can be best summed up by its slogan - “Safe, secure and efficient shipping on clean oceans.” It was established by means of a convention adopted in Geneva in 1948, and first met in 1959. Based in the United Kingdom, as of 2010 the IMO has 169 member states and three associate members.


Chemically inactive; in other words, a substance is inert if it does not react to or combine with other substances or chemicals. A substance is inert if it is without active chemical properties.


Intruding: involving an invasion, intrusion or infringement.


Burdened, carrying, bearing.


Leaching refers to the process of dissolving a soluble component out of a constituent material at a wetted surface. Materials commonly leached into drinking water from water distribution systems include copper, lead, and nickel. In the case of antifouling paint, the copper and other toxic material contained in the paint gradually dissolves out of the paint base into the water in an attempt to poison the marine organisms as they try to attach to the ship hull or after they have done so.


The average length of life of a kind of organism or of a material object especially in a particular environment or under specified circumstances.

Lloyd’s Register-Fairplay

Lloyd’s Register, The Lloyd’s Register Group is a maritime classification society and independent risk management organization providing risk assessment and mitigation services and management systems certification. Historically, as Lloyd’s Register of Shipping, it was a specifically maritime organization. In the late 20th century, it diversified into other sectors including oil & gas, process industries, nuclear and rail. Since 1880, the Register, with information on all sea-going, self-propelled merchant ships of 100 gross tonnes or greater, has been published annually by the joint venture company of Lloyd’s Register-Fairplay. Lloyd’s Register-Fairplay is responsible for many maritime publications and is a repository of information about shipping and the shipping industry.


A boat basin offering dockage and other service for small craft.

Marine fouling

Fouling refers to the accumulation of unwanted material on solid surfaces, most often in an aquatic environment. The fouling material can consist of either living organisms (biofouling) or a non-living substance (inorganic or organic) and is often a combination of the two. Fouling is usually distinguished from other surface-growth phenomena in that it occurs on a surface of a component, system or plant performing a defined and useful function (such as a ship hull or propeller), and the fouling process impedes or interferes with this function. An accumulation of marine growth on the rocks of a port would not be considered fouling, whereas the same accumulation on a ship’s hull, propeller or anchor cable would be.


Material in which something is enclosed or surrounded.


Of a vessel, secured in a certain position as by a cable or anchor.


The changing of structure of a gene resulting in a variant form which can then be transmitted to future generations.

NIS or Non-indiginous Species, Alien Species or Invasive Species (sometimes NIMS, non-indigenous marine species):

An introduced, alien, exotic, non-indigenous, or non-native species, is a species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental. Some introduced species are damaging to the ecosystem they are introduced into and then reach invasive status, negatively affecting the local ecosystem.


The time during which a vessel is not available for service, such as when it is in drydock.


Particulates, alternatively known as particulate matter (PM), or fine particles. Particulate matter can be emitted into the atmosphere as a result of combustion of coal or oil or other substances and is a form of pollution.


Polydimethylsiloxane is a clear, viscous substance normally referred to as dimethicone, one of several types of silicone oil.


Platelets are small plate or disk shaped particles or fragments. Ecospeed uses glass platelets specially designed to resist water ingress in the marine environment. Glass is a natural barrier to water and is often used for this purpose in glass flake lining technology. The term platelet is preferred for Ecospeed, because the glass particles used in Ecospeed have a unique, plate-like form.


Substances, material, gases, liquids that make land, water or air dirty and unhealthy.

Pore water

Pore water is the water that fills the spaces of a sediment.


Is a prefix meaning, “later”, “subsequent to”.


Directly after leaving drydock where, presumably, the hull has been blasted and repainted; before any fouling has accumulated on the hull.

Propagule pool

A group of in this case species or taxa available to be drawn from or to spread.


A resin is a vegetable product formed by secretion in most trees and plants and are used in making varnishes or glues. A synthetic resin is a man-made compound of similar qualities. Resins applied to a surface form a thin, hard layer on that surface.


The polymer (plastic) part of a paint that cures to form into a coat of paint.


Roll-on/roll-off (RORO or ro-ro) these are vessels designed to carry wheeled cargo such as automobiles, trucks, semi-trailer trucks, trailers or railroad cars that are driven on and off the ship on their own wheels. RORO vessels have built-in ramps which allow the cargo to be efficiently “rolled on” and “rolled off” the vessel when in port.


Matter composed of particles which fall by gravitation to the bottom of a liquid.


A semi-submersible is a specialized marine vessel with good stability and seakeeping characteristics. The semi-submersible vessel design is commonly used in a number of specific offshore roles such as for offshore drilling rigs, safety vessels, oil production platforms and heavy lift cranes. Usually the semi-submersible is self-propelling.


Silicones are largely-inert, man-made compounds with a wide variety of forms and uses. Typically heat-resistant, nonstick, and rubber-like, they are commonly used in cookware, medical applications, sealants, adhesives, lubricants and insulation. They are also used in hull coatings which are designed to make it difficult for fouling to adhere to the hull and easy for the marine organisms to be released from the surface (hence the name foul-release coatings for this type of hull protection).

STC (Surface Treated Composite)

A composite is a substance made up of different parts combined together. For example, in the case of the Ecospeed hard coating for ship hulls, the coating is made up of glass platelets in high concentration in a vinyl ester resin base. Mix the glass in with the resin and, when cured, the result is a very hard, long-lasting coating. Surface Treated here refers to the fact that the Ecospeed protection system is not in final form until it has been conditioned in the water using specialized hydraulic and abrasive brushing equipment. This polishes the surface, removing a micron or two of resin, and leaving behind an extremely hard, smooth surface. Subsequent cleaning of the hull further improves the smoothness and hydrodynamic performance of the coating without damaging it in any way. This is what is meant by a Surface Treated Composite or STC. It is completely inert, does not leach chemicals, biocides or oils into the water as is the case with traditional antifouling or foul-release coatings. An STC is therefore entirely non-toxic. The hard smooth surface is ideal for in-water cleaning, particularly at the slime or light weed stage, but even if heavily fouled it can be cleaned and restored to its original condition without damage or deterioration.


The technology of ship design that reduces radar returns and makes the ship difficult to detect. Sloping shapes deflect radar signals and make the ship virtually invisible.


(plural of taxon) A taxon is group of organisms classified by similarities of structure or origin etc. Taxa is plural and therefore means more than one taxon.


Tributyltin, tributyltinhydride or TBT is a highly toxic substance that since the beginning of the 1970s was often used in paints to prevent fouling such as algae and barnacles on ship hulls (antifouling). The use of paints containing TBT has been banned since January 2003.


Biology any agent (person or animal or microorganism) that carries and transmits a disease.

Vinyl ester resin

Without getting into the chemistry of it, vinyl ester resin is a very tough, corrosion resistant, highly adhesive synthetic compound favored as a marine coating. In Ecospeed it forms the base or matrix which holds the glass platelets together and attaches them extremely firmly to the hull.


Very Large Crude Carrier a vessel designed for the carriage of liquid cargo in bulk with a loading capacity from 150,000 to 250,000 DWT (deadweight tonnage).

White paper

A white paper is an authoritative report or guide that is often oriented toward a particular issue or problem. White papers are used to educate and inform readers and help them make decisions, and are often requested and used in politics, policy, business, and technical fields.

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