Flashcards in Chapter 14 - Foam Equipment and Systems Deck (61)
Some of the major reasons for the increase in use of foam products include: (4)
> Magnitude and frequency of hazardous materials incidents that require foam operations for mitigation.
> Newer foam concentrates are more easily used by structural and wildland firefighters.
> Improvements in the design of foam proportioning equipment and systems have made their inclusion in apparatus more feasible.
> Use of foam may help reduce water usage; a significant factor where supply is limited.
_________ ____ are the most common foams in use.
These products must be ____________ (mixed with water) and ________ (mixed with air) before use
To produce fire fighting foam, ____ _______, _____, and ___ must be ________ or injected in the correct ratios.
Raw foam liquid in its storage container before being combined with water and air.
Device that injects the correct amount of foam concentrate into the water stream to make the doam solution.
Mixture of foam concentrate and water before the introduction of air.
Completed product after air is introduced into the foam solution. (Also known as Finish Foam)
Class B fuels are divided into two categories:
Hydrocarbons and Polar Solvents
__________ ____, such as crude oil, fuel oil, gasoline, benzene, and kerosene, are petroleum based and have a specific gravity of less than one and will float on water.
______ _______ _____, such as alcohol, acetone, ketones, and esters, are known as miscible liquids because they mix with water.
Polar Solvent Fuels
_______ foams are designed solely for use on hydrocarbon fuels and are not effective on polar solvent products regardless of the concentration that is applied.
Class B Foams
Foam extinguishes and/or suppresses vapors by the following methods:
> Separating - Creates a barrier between the fuel and the fire.
> Cooling - Lowers the temperature of the fuel and adjacent surfaces.
> Suppressing or smothering - Prevents the release of flammable vapors, reducing the possibility of ignition or reignition.
____________ is the act of mixing of water with foam concentrate to form a foam solution.
Most fire fighting foam concentrates are formulated to mix with a___ to _____ percent water.
94 to 99.9%
Class A foam percentages may range from as little as ____ percent to __ percent.
0.1 to 1 %
Foam is proportioned by using one of four basic methods:
> Batch Mixing
Four common methods of foam storage for most fire service applications are:
> Apparatus Tanks
Five-gallon plastic _____ are commonly used containers in many municipal fire departments.
Foam concentrate is also available in 55- gallon plastic or plastic-lined _______.
When bulk storage of foam concentrates is required, some fire departments or industrial facilities may specify 275-gallon containers, called _______.
Foam concentrate tanks on municipal fire apparatus generally range from ___ to ____ gallons while foam pumpers or tenders may carry _____ gallons or more of concentrate.
20 to 200
The majority of foam concentrates are divided for use on either ______ __ (ordinary combustibles) or _____ __ (Flammable liquids) fuels.
Class A or Class B
_______ ___ foam may be used with fog nozzles, aerating foam nozzles, and medium and high expansion devices; and compressed air foam systems using most nozzles, including solid stream nozzles.
Class A foam
______ __ foam concentrates my be mixed with percentages as little as ___ to ____ percent.
0.1 to 1.0 %
The following guidelines are commonly used for proportioning Class A Foam:
> Fire attack and overhaul with standard fog nozzles - 0.2 to 0.5%
> Exposure protection with standard fog nozzles - 0.5 to 1.0%
> Any application with air aspirating foam nozzles - 0.3 - 0.7%
> Any application with CAFS - 0.2 to 0.5%
The __________ ____ refers to the minimum amount of foam solution that must be applied to a fire, per minute, per square foot of fire.
These foam concentrates (______ __) consist of a sythetic or protein base. While synthetic foam is made from a mixture of flourosurfactants, protein based foam is derived from animal protein
Class B foams are mixed in proportions from ____ to ____ percent
1 to 6%