Principles of
Foam Fire Fighting (1st Edition)
Complete List of Terms
25 Percent Drain Time
The time required in minutes for one-fourth of the total
liquid solution to drain from a foam blanket. Synonymous with Quarter-Life
and Quarter Drain Time.
Actuator
A triggering device, most commonly heat or flame detection-driven, used on
automatic protection systems.
Adhesion
The act of binding together substances of unlike compositions.
Adverse
Abnormal or unusual; as in conditions.
Aeration
The introduction of air into a foam solution to create bubbles that result in
finished foam. Synonymous with Foam Expansion.
Alternative Fuel Vehicle
A vehicle which runs on fuel other than gasoline.
Anchor Point
A safe, secure area where a wildfire attack begins.
Application Rate
The minimum amount of foam solution that must be applied to a fire, per minute,
per square foot of fire.
Approach Suit
Special personal protective gear designed to protect
against radiant heat while approaching the fire.
Aspirated Foam
Foam that has air injected into the stream.
Auto-Ignition Temperature
Temperature at which a substance will ignite without an
outside ignition source.
Axiom
A self-evident or necessary truth.
Backdraft
Condition created by a sudden inflow of fresh air to an
oxygen-deficient smoldering fire which creates an explosion.
Backfire
Technique used in the indirect attack method for natural cover fires in which a
fire is intentionally set between the control line and the advancing fire.
Backpressure
Pressure loss or gain created by changes in elevation between the nozzle and the
pump.
Bank-Down Method
A method of foam application that is employed when an
elevated object is near or within the area of a burning pool of liquid in which
the foam is directed off of the elevated object, allowing the foam to run down
onto the surface of the fuel.
Batch-Mixing
The making of foam solution by pouring an appropriate amount of foam concentrate
into a water tank.
Biodegradable
Capable of being broken down into innocuous products by the action of living
things, such as microorganisms.
Boilover
Overflow of crude oil from its container when the heat wave reaches the water
level in the tank which causes water to turn to steam and a violent expulsion of
the material occurs.
British Thermal Unit
The amount of heat required to raise one pound of water one degree Fahrenheit.
Burnback Resistance
The ability of a foam blanket to resist direct flame impingement such as would
be evident in a partially extinguished petroleum fire.
Chemical Foams
Foams produced as a result of a reaction between two chemicals.
CHEMTREC/CANUTEC
Organization which acts as a source of information on chemicals and physical
characteristics of products.
Class A Fire
Class of fire involving normal combustibles such as wood, paper, and cloth.
Class A Foam
Foam specially designed for use on ordinary combustibles such as wood, paper,
and cloth.
Class B Fire
Class of fire involving flammable and combustible liquids and gases such as
gasoline, kerosene, and propane.
Class B Foam
Foam designed to be used on spills or fires involving flammable or combustible
liquids.
Class C Fire
Fires involving energized electrical equipment.
Cohesion
The act of binding together substances of like composition.
Combies Aircraft
Large aircraft with a passenger cabin in the front of the aircraft and a
separate cargo compartment in the rear of the aircraft. Synonymous with
Combination Aircraft.
Combination Aircraft
Large aircraft with a passenger cabin in the front of the aircraft and a
separate cargo compartment in the rear of the aircraft. Synonymous with
Combies Aircraft.
Combustible Liquid
A liquid having a flash point at or above 100oF and below 200oF.
Commercial Aviation Aircraft
Airline, commuter, cargo, and fire fighting aircraft classification.
Conduction
Transfer of heat through direct contact between two objects or through contact
with an intervening medium that transfers heat.
Conductivity
The ability of a substance to conduct an electrical current.
Conduit
A pipe or channel.
Confinement
The process of controlling the flow of a spill and capturing it at a specified
location; or, fire fighting operations required to prevent fire from extending
to uninvolved areas or structures.
Containment
The act of stopping the further release of a material from its container.
Containment Boom
A floating physical barrier serving as a continuous obstruction to the spread of
a contaminant.
Convection
Transfer of heat by the movement of fluids such as air or water.
Cooling
The act of lowering the temperature of the fuel and adjacent surfaces.
Corrosives
Those materials that cause harm to living organisms by destroying body tissues.
Dead-Man Valve
A spring-loaded valve that controls the flow of fuel from a loading rack to a
tank and is designed to shut off immediately when the operator releases the
handle.
Declared Emergency
An aircraft emergency in which an aircraft crew is aware that there is a problem
and before they prepare to land notify the airport authorities of the emergency.
Decomposition
The breakdown of a substance over time due to chemical action or natural decay.
Defensive Attack
Exterior fire attack with emphasis on exposure protection.
Density
Weight per unit volume of a substance which is obtained by dividing the weight
by volume.
Diked Areas
Areas that are either bounded by natural or man-made barriers intended to keep
spilled fuel within these boundaries.
Direct Attack
Application of a fire stream directly onto a burning fuel; or, to attack a
natural cover fire at or close to the burning edge.
Drainage Dropout Rate
The amount of time it takes for foam to break down. Synonymous with
Drainage Rate and Drainage Time.
Drainage Rate
The amount of time it takes for foam to break down. Synonymous with
Drainage Rate and Drainage Dropout Rate.
Drainage Time
The amount of time it takes for foam to break down. Synonymous with
Drainage Rate and Drainage Dropout Rate.
Dry Foam
Foam that has a very high air-to-foam solution ratio.
Eductor
Portable proportioning device that injects a liquid, such as foam concentrate,
into the water flowing through a hoseline.
Electromagnetic Waves
Waves of heat radiated from an object of critical importance to exposure
protection.
Engine Nacelles
The protective housing surrounding the working parts of the engine.
Envelopment
Attacking key or critical segments around the entire fire perimeter at the same
time.
Explosive Limit
Percentage of a substance in air that will burn once ignited. Synonymous
with Flammable Limit.
Explosive Range
The range between the upper flammable limit (UEL) and lower flammable limit (LEL)
in which a substance can be ignited. Synonymous with Flammable Range.
Exposure Protection
Covering any object in the immediate vicinity of the fire with water or foam.
Feed
To add to the intensity of.
Fire Flow
Quantity of water available for fire fighting in a given area; or, the amount of
water required to extinguish a fire in a timely manner.
Fire Point
Temperature at which a liquid fuel produces sufficient vapors to support
combustion once the fuel is ignited. Synonymous with Burning Point.
Fire Tetrahedron
Model of the four elements required to have a fire in which the four sides
represent fuel, heat, oxygen, and chemical chain reaction.
Fire Triangle
Plane geometric figure in which the three sides of an equilateral triangle
represent oxygen, heat, and fuel, the elements necessary to sustain combustion.
Flame Spread
The spreading of flames from a point of origin to near by combustibles.
Flammable Limit
Percentage of a substance in air that will burn once ignited. Synonymous
with Explosive Limit.
Flammable Liquid
Any liquid having a flash point below 100oF and having a vapor
pressure not exceeding 40psi absolute.
Flank
Sides of a natural cover fire.
Flanking
Attacking the sides of the fire from a less active area or from an anchor point.
Flashover
Stage of fire at which all surfaces and objects within a space have been heated
to their ignition temperature and flame breaks out almost at once over the
surface of all objects in the space.
Flow Rate
The velocity at which water or a waterous solution flows through fire hose or
appliances.
Foam
Extinguishing agent formed by mixing foam concentrate with water and aerating
the solution for expansion. Also known as finished foam.
Foam Concentrate
The raw foam liquid as it rests in its storage container prior to the
introduction of water and air.
Foam Expansion
The introduction of air into a foam solution to create bubbles that result in
finished foam. Synonymous with Aeration.
Foam Monitor
A foam master stream nozzle.
Foam Proportioner
Device that injects the correct amount of foam concentrate into the water stream
to make the foam solution.
Foam Solution
Mixture of foam concentrate and water after it leaves the proportioner but
before it is discharged from the nozzle and air is added to it.
Foam Stability
The relative ability of foam to withstand spontaneous collapse or breakdown from
external causes.
Forcing Foam Maker
An in-line aspirator used to deliver foam under pressure in which air is
supplied directly to the foam solution through a venturi action.
Synonymous with High-Backpressure Foam Maker.
Frangible
Easily broken; used in many automatic fire protection systems.
Free-Burning Phase
Generally considered the phase of the fire where sufficient oxygen and fuel are
available for fire growth and open burning to a point where total involvement is
possible. Synonymous with Steady-State Phase.
Frontal Attack
Situation where the crew begins the attack from an anchor point at or near the
head of the fire and then proceeds to the flanks.
General Aviation Aircraft
Aircraft used for pleasure or training, business, or agricultural purposes.
Handline Nozzle
Any nozzle that can be safely handled by one to three firefighters and flows
less than 350gpm.
Heat Resistance
A foam's ability to resist the actual heat of the liquid or surface on which it
is applied.
High-Backpressure Foam Maker
An in-line aspirator used to deliver foam under pressure in which air is
supplied directly to the foam solution through a venturi action.
Synonymous with Forcing Foam Maker.
High-Impact Crashes
Aircraft crashes with severe damage to the fuselage and with a significantly
reduced chance of occupant survival.
Homogenous
A substance having uniform structure or composition throughout.
Hot-Smoldering Phase
Phase of combustion when the level of oxygen in a confined space is below that
needed for flaming combustion and is characterized by glowing embers, high heat
at all levels of the room, and heavy smoke and fire gas production.
Hydrocarbon
An organic compound containing only hydrogen and carbon and found primarily in
petroleum products and coal.
Hydrolyze
A chemical process of decomposition involving splitting of a bond and the
addition of the elements of water.
Hypergolics
A chemical reaction between a fuel and an oxidizer that causes immediate
ignition on contact without the presence of air.
Immiscible
Not capable of mixing together.
Impingement
To move upon as in flame.
Incipient Phase
First phase of the burning process where the substance being oxidized is
producing some heat, but the heat has not spread to other substances nearby and
the oxygen in air has not been significantly reduced.
Incompressible
Inability to be compressed into a smaller space.
Indirect Attack
Directing the fire stream at the ceiling level of a room or building in order to
generate a large amount of steam which in turn darkens the fire and cools the
area so that firefighters may enter and make a direct attack; or, a method of
controlling a wildfire where the control line is constructed or located some
distance from the edge of the main fire.
In-Flight Emergencies
Emergencies that include fires as well as other problems that may cause or
contribute to fire such as hydraulic failure, engine failure, landing gear
malfunction, or other system malfunctions of an aircraft that is in flight.
Inherent
An essential characteristic; intrinsic quality.
Inorganic Acid
An acid generally does not contain carbon and will not burn.
Jettisoned
Removal of an object from an aircraft while in flight.
Joule
The amount of heat energy provided by one watt flowing for one second.
Knockdown
To reduce in size or contain.
Life of Foam
The period of time that the foam blanket remains in place until more foam must
be applied.
Loading Racks
Fixed facilities where either truck or
railroad tank cars are bulk loaded with flammable and combustible liquids.
Low-Expansion Foam
A form of foam which creates an aqueous film that floats on top of fuels; also
called "light water".
Low-Impact Crashes
Aircraft crashes that do not severely damage or break up the fuselage and are
likely to have a large percentage of survivors.
Mechanical Foam
Foam produced by physical agitation of a mixture of water, air, and a foaming
agent.
Mechanical Shoe Seal
A fabric seal that is anchored to the top of the roof and
rides on the inside of a large fuel storage tank wall. Synonymous with
Pantograph Seal.
Military Aviation Aircraft
Classification of aircraft which includes cargo, fighter, bomber, trainer, and
special mission aircraft.
Miscible
The ability to mix together.
Mitigated
End process of lessening severity or danger from a situation.
Mobile Foam Apparatus
Apparatus used to fight large-scale flammable and combustible liquid fires in
areas that are not protected by fixed systems.
Non-Intervention
Allowing the fire to burn until all fuel has been consumed.
Octane
A characteristic of petroleum products which indicates its burning efficiency.
Oleophobic
The characteristic of shedding oil.
Opaque
Impenetrable to light.
Organic Acid
An acid that contains carbon and will burn.
Orifice
A hole or small opening.
Overproportioning
The result of to much foam concentrate being educted into the water stream due
to incorrect settings or a clogged orifice.
Oxidation
Chemical reaction in which oxygen combines with other elements.
Oxidizer
Substance that yields oxygen readily and may simulate the combustion of organic
and inorganic matter.
Pantograph Seal
A fabric seal that is anchored to the top of the roof and
rides on the inside of a large fuel storage tank wall. Synonymous with
Mechanical Shoe Seal.
Peripheral
To the side; outer edge.
Point and Cut Off
Attacking several heads or fingers of a wildfire at the same time and then
connecting the short line segments.
Polar Solvents
Flammable liquids that have an attraction to water.
Positive Heat Balance
Situation in which heat is fed back to the fuel.
Preclude
To rule out by circumstance.
Premixing
Mixing premeasured portions of water and foam concentrate in a container.
Proportioning
The mixing of water with an appropriate amount of foam concentrate to form a
foam solution.
Proximity Suit
Specialized protective gear which has an aluminized surface to allow
firefighters to move in close to put out a fire.
Purge
The process of emptying.
Pyrolysis
Chemical decomposition caused by heat that generally results in the lowered
ignition temperature of a material.
Quarter Drain Time
The time required in minutes for one-fourth of the total
liquid solution to drain from a foam blanket. Synonymous with 25 Percent
Drain Time and Quarter Drain Time.
Quarter-Life
The time required in minutes for one-fourth of the total
liquid solution to drain from a foam blanket. Synonymous with 25 Percent
Drain Time and Quarter Drain Time.
Radiation
Transfer of heat through heat waves (infrared).
Radiative Feedback
Radiant heat providing energy for continued vaporization.
Rain-Down Method
A method of foam application in which the foam stream is directed into the air
and allowed to gently float down onto the surface of the fuel.
Rate of Vaporization
The speed at which a liquid evaporates or vaporizes.
Refractometer
A device used to measure the amount of foam concentrate in a solution.
Reignition
To re-enter flame state due to inadequate extinguishment.
Residual Fuel
Unburned fuel left behind after a fire.
Resistance to Freezing
A foam concentrate's usefullness after it has been frozen and then thawed.
Retention
The characteristic of Class A foam and foam solution to remain on and in the
fuel, reduce the fuel temperature, and increase the fuel moisture content.
Roll-On Method
A method of foam application in which the foam stream is directed onto the
ground near the front edge of a liquid pool on fire and rolls across the surface
of the fuel.
Rollover
Unburned superheated combustible gases released during the incipient or early
steady-state phase that accumulate at ceiling level and are pushed, under
pressure, away from the fire area and into uninvolved areas where they mix with
oxygen and ignite once reaching their ignition temperature resulting in flames
rolling across the ceiling.
Rotor
Part of a helicopter that provides for lateral and vertical movement.
Semisubsurface Injection
A process in which foam is discharged through a flexible
hose that rises from the bottom of a tank, up through the fuel, and to the
surface.
Separating
The act of creating a barrier between the fuel and the fire.
Shelf Life
The time period that a product will work if stored properly prior to use.
Ship
Another name for aircraft.
Size-Up
Mental evaluation made by the operational officer in charge that enables them to
accomplish the mission; or a mental evaluation process that evaluates all
influencing factors before committing personnel and equipment to a course of
action.
Skin
The outer covering of an aircraft.
Skydrol
A type of synthetic hydrocarbon hydraulic fluid used in some aircraft.
Solubility
Degree to which a solid, liquid, or gas dissolves in a solvent.
Specific Gravity
Weight of a substance compared to the weight of an equal volume of water at a
given temperature.
Static Source
Body of water that is not under pressure or in a supply piping system and must
be drafted from in order to be used.
Steady-State Burning Phase
Generally considered the phase of the fire where sufficient oxygen and fuel are
available for fire growth and open burning to a point where total involvement is
possible. Synonymous with Free-Burning Phase.
Structure Fire
Fire that involves a building, enclosed structure, vehicle, vessel, aircraft, or
like property.
Subsurface Injection
A process by which foam is pumped into the bottom of a
burning petroleum tank and allowed to float to the top to form a fire
extinguishing blanket.
Suppressing
The act of preventing the release of flammable vapors and therefore reducing the
posibility of ignition or reignition. Synonymous with Smothering.
Surface Tension
The effect of a surfactant on the water/concentrate solution that allows the
water to spread more rapidly over the surface of Class A fuels and penetrate
organic fuels.
Surface-to-Mass Ratio
The ratio of the surface area of a fuel in relation to the mass of the fuel.
Surfactant
A chemical that lowers the surface tension of a liquid.
Tender
A tanker that transports large quantities of foam concentrate when needed.
Topography
Physical features of the earth's surface. Synonymous with Terrain.
Training Concentrates
Foam concentrates that are designed specifically for
training and are formulated for hydrocarbon fuel fire training.s
Tube Seal
A type of seal used on floating roof storage tanks in which the seal is
constructed of urethane and is contained in an envelope.
Turret
A large master stream appliance mounted on a pumper or
trailer and connected directly to a pump. Synonymous with Deck Gun or Deck
Pipe.
Undeclared Emergency
An aircraft emergency that occurs without prior warning.
Vapor Density
Weight of a given volume of gas or vapor compared to the weight of and equal
volume of air at the same temperature and pressure.
Vapor Suppression
The action taken to reduce the emission of vapors at a fuel spill.
Vaporization
Passage from a liquid to a gaseous state.
Venturi
Situation in which a fluid is forced under pressure through a restricted orifice
resulting in a decrease in the pressure exerted against the side of the
constriction and causes a corresponding increase in the velocity of the fluid.
Viscosity
A liquid's thickness or ability to flow.
Volatility
The ability of a substance to vaporize easily at a relatively low temperature.
Volume
The space occupied by a substance.
Wildfire
An unplanned, unwanted, and uncontrolled fire involving vegetative fuels that
often threatens structures.
Wildfire Mop-Up
Operations involving extinguishing hot spots and hidden fires after the main
body of fire has been knocked down. Synonomous with Mop-Up.
Wildland/Urban Interface
Areas where wildlands meet developed areas.