NIMASA STCW FPFF key terms

The three elements needed for combustion: fuel, oxygen and a source of heat. Removing any one of them stops the fire, which is the basis of every extinguishing method used on board.

A four-sided model adding the chemical chain reaction to fuel, oxygen and heat. It explains why chemical extinguishing agents such as dry powder and clean agents can break a fire that still has all three physical elements present.

The lowest temperature at which a liquid gives off enough vapour to ignite briefly when a small flame is applied. It is the key figure deciding how a flammable liquid is stored, labelled and handled on board.

The temperature at which a substance ignites spontaneously without any external flame or spark. Hot shipboard surfaces such as exhaust manifolds, steam lines and heater coils can reach it and start a fire.

The band of vapour concentrations in air between the lower and upper explosive limits within which a gas or vapour will burn. Below or above this band the mixture is too lean or too rich to ignite.

The minimum concentration of flammable vapour in air that will support combustion. Gas detectors on tankers and pump rooms usually read in percentage LEL, and alarms sound well before the atmosphere reaches it.

Any energy input capable of starting combustion, including open flame, hot surfaces, electrical arcing, static discharge, friction sparks and spontaneous heating. Fire prevention work is largely about identifying and controlling these sources.

Self-heating of a material until it ignites, caused by slow oxidation or biological activity that produces more heat than can escape. Oily rags, coal cargoes and some agricultural products are common shipboard examples.

A liquid that gives off ignitable vapour at normal working temperatures, generally one with a flashpoint at or below 60 degrees Celsius in closed cup. Its vapour, not the liquid itself, burns.

Any operation producing heat, flame or sparks, such as welding, cutting, grinding or brazing. It needs a written permit, gas-freeing, fire watch and removal or protection of combustibles before it may start.

A formal written authorisation issued by a responsible officer before welding or similar work. It records the location, precautions taken, gas readings, fire watch arrangements and the time the work must stop.

A person stationed at a hot work site with extinguishing equipment, tasked to watch for ignition and to raise the alarm. The watch normally continues for a set period after the work finishes to catch smouldering material.

The routine control of combustible and ignition hazards in spaces: removing oil-soaked rags, keeping paint and solvents in lockers, clearing rubbish and preventing oil accumulation. Poor housekeeping is a leading cause of shipboard fires.

A permanently installed arrangement of smoke, heat or flame detectors connected to a control panel that indicates the affected zone. It gives early warning in spaces that are normally unmanned, such as holds and machinery spaces.

The control unit that receives signals from detectors and manual call points and shows the zone in alarm. It usually includes fault indication and repeaters on the bridge and in the engine control room.

A hand-operated device, usually a break-glass or push element, that raises the general alarm when a fire is discovered. Crew should know its locations along escape routes in their area of responsibility.

The shipwide signal of seven or more short blasts followed by one long blast on the whistle and internal alarm, summoning crew to muster stations. It is often followed by a spoken announcement naming the emergency.

A permanently piped or containerised extinguishing system serving a whole space, such as CO2, foam, water spray or inert gas. It is operated from a control station after the space is evacuated and sealed.

A fixed installation that discharges carbon dioxide into a sealed space to reduce oxygen below the level supporting combustion. It is lethal to people, so the space must be evacuated, accounted for and clearly marked before release.

The pressurised pipeline supplying hydrants, hoses and fixed water systems throughout the ship, fed by fire pumps. Its pressure and availability are checked during drills and before any firefighting operation.

A pump dedicated to supplying the fire main at the required pressure and capacity, with an emergency pump fitted outside the machinery space. Correct starting and priming procedure is a routine drill item.

A valved outlet on the fire main where a hose is connected. Crew must know how to open it slowly, confirm the correct branch is charged and drain and stow the hose afterwards.

The interlocking end fitting that joins hose lengths to each other, to the hydrant and to the nozzle. Standard types such as instantaneous and Storz couplings must be matched and secured correctly to avoid failure under pressure.

The branch fitting at the end of a fire hose that shapes and directs the water jet, often adjustable between solid stream, spray and shut-off. Spray pattern choice affects reach, cooling and protection of the firefighter.

A wide cone of fine water droplets produced by a spray nozzle, giving large surface cooling and shielding the firefighter from radiant heat. It is widely used for boundary cooling and gas cooling in compartments.

A hand-carried appliance containing water, foam, dry powder or CO2 for first-aid attack on a small fire. Selection depends on the fire class, and the extinguisher must be checked, pin removed and aimed correctly before use.

A fire involving solid combustible materials such as wood, paper, textiles and rubbish, which leaves ash and needs cooling. Water and water-based agents are the usual choice because they soak into the material.

A fire involving flammable liquids such as oil, fuel, paint or solvents. Foam, dry powder and CO2 are used, while a solid water stream can spread the burning liquid and is avoided.

In the classification used in many training schemes, a fire involving flammable gases such as LPG or acetylene. The priority is to stop the gas supply and cool the container before extinguishing, to prevent re-ignition or explosion.

A fire involving combustible metals such as magnesium, aluminium powder or sodium. Special dry powder agents are required, and water, foam and CO2 are dangerous because they can react violently.

A fire involving cooking oils and fats in deep-fat fryers and galley equipment. Wet chemical extinguishers are used because a water jet would cause violent spitting and spread the burning oil.

An extinguisher containing an alkaline solution that reacts with hot cooking oil to form a soapy blanket, cooling and sealing the surface. It is the specified agent for galley deep-fat fryer fires.

An extinguishing medium of bubbles that blankets a burning liquid, cutting off oxygen and suppressing vapour release. It is applied gently onto the surface, never plunged into the liquid, and is the main agent for tank and spill fires.

Extinguishing a fire by excluding oxygen, for example with foam, CO2, a fire blanket or by closing hatches and vents. It is the standard method for enclosed spaces and for liquid fires.

Extinguishing a fire by removing or shutting off its fuel supply, such as closing a fuel valve or stopping a gas leak. It is often the safest first action because it removes the source of continued burning.

Reducing the temperature of burning material and surrounding structures below the level that supports combustion, usually with water. It is the main method for solid fires and the basis of boundary cooling.

Breaking the chemical chain reaction of a fire using agents such as dry powder or clean agents. It gives rapid knockdown, but cooling may still be needed to prevent re-ignition of hot surfaces.

A multi-purpose extinguishing agent that inhibits the chain reaction and is effective on liquid, gas and electrical fires. It leaves residue that can damage machinery and obscure vision, and it offers little cooling.

Applying water to bulkheads, decks and structures around a fire to keep them below their ignition or structural failure temperature. It limits spread and protects adjacent spaces, and is a core team task at the fire scene.

Closing openings, stopping fans and operating dampers to limit the supply of air to a fire and to control smoke movement. It must be coordinated with the attack, since sudden air admission can cause flashback.

The sudden spread of fire across all combustible surfaces in a compartment as hot gases ignite everything at once. It marks the point where the space becomes untenable and entry requires full protective equipment and charged hoses.

An explosive ignition of unburnt gases when air is suddenly admitted to a hot, oxygen-starved compartment. It is why doors are opened cautiously from behind cover with a charged hose ready.

A group of crew assigned specific firefighting duties such as attack, backup, boundary cooling or first aid. Members must know their team number, leader and equipment before any emergency occurs.

The designated assembly point where crew report on hearing the general emergency alarm so they can be accounted for and tasked. It is marked on the muster list and on posted plans throughout the ship.

The posted document assigning every person on board a station and duty for emergencies such as fire, abandon ship and man overboard. It also names replacements for key roles who may be unavailable.

The officer in charge at the fire itself, directing the attack teams and reporting to the command centre. This person controls tactics, entry and withdrawal and keeps the bridge informed of progress.

A planned exercise rehearsing alarm response, muster, equipment use and firefighting tactics. Drills must be recorded, and their frequency and content are subject to statutory inspection.

The protective clothing and equipment worn for firefighting, including fire-resistant suit, helmet, gloves, boots and hood. It protects against heat, flame and steam but does not permit entry to a space without breathing apparatus.

Self-contained breathing apparatus: a back-carried cylinder and face mask supplying breathable air independent of the surrounding atmosphere. It is mandatory for entry into smoke-filled or potentially toxic spaces.

The procedure of logging each person entering a fire space, recording time in, air supply and task, and controlling relief and withdrawal. It ensures no one is unaccounted for if conditions deteriorate.

A standby team, equipped and briefed, held ready to enter and recover firefighters in difficulty. It must be positioned before the attack team enters and never used for routine tasks.

A scheduled round of designated spaces by a crew member to look for fire, smoke, leaks and unsafe conditions. It provides a human backup to fixed detection, especially in spaces with limited automatic cover.

A portable or fixed instrument measuring flammable vapour, oxygen or toxic gas concentration in an atmosphere. Readings in percentage LEL and oxygen percentage guide entry decisions and hot work permits.

The structured examination of a fire's origin, cause and spread, begun as soon as the scene is safe. Observations, photographs and witness statements are gathered before clean-up destroys evidence.

A post-fire watch kept on the scene to detect and extinguish renewed burning in hot or smouldering material. It continues until temperatures are confirmed safe, often with thermal checks and a charged hose in place.

The formal written record of a fire, covering time, location, cause, action taken, equipment used and injuries. It supports investigation, statutory notification and lessons learned for future drills.