Essentials of Fire Fighting (4th Edition)
Chapter 13 FF2 Terms
Fire Streams
Aerated
Mixed with air.
AFFF
(Aqueous Film-Forming Foam)-Synthetic foam concentrate that, when combined with water, is a highly effective extinguishing and blanketing agent on hydrocarbon fuels.
Batch Mixing
Process of adding foam concentrate directly into an apparatus water tank or portable tank.
Biodegradable
Characteristic of foam's ability to decompose by interaction with environmental bacteria.
Cooling
Reduction of heat by the quenching action or heat absorption of the extinguishing agent.
Eductor
Portable proportioning device that injects a liquid, such as foam concentrate, into the water flowing through a hoseline.
FFFP
(Film-Forming Fluouroprotein Foam)-Foam concentrate that is based on fluoroprotein foam technology with aqueous film forming foam (AFFF) capabilities.
Foam Concentrate
Raw chemical compound solution that is mixed with water and air to produce foam.
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.
Induction
Method of proportioning foam in which pressure energy in a stream of water is used to draft foam concentrate into the fire stream by use of an eductor (Venturi principle).
Injection
Method of proportioning foam in which external pump or head pressure is used to force foam concentrate into the fire stream at the correct ratio in comparison to the flow.
Premixing
Process of mixing pre-measured portions of water and foam concentrate in a container, commonly used with portable and wheeled extinguishers.
Proportioned
Term used to describe the final product of two or more items that have been combined using pre-determined/pre-measured portions of each item.
Separating
Creation of a barrier between the fuel and the fire.
Suppressing
Preventing the release of flammable vapors, therefore reducing possibility of ignition or re-ignition. Also called Smothering.
Venturi Principle
When a fluid is forced under pressure through a restricted orifice, there is a decrease in the pressure exerted against the side of the constriction and a corresponding increase in the velocity of the fluid. Because the surrounding air is under greater pressure, it rushes into the area of lower pressure.