Ch. 14 Foam Flashcards
(39 cards)
ch. 14 pg. 479
To produce Fire Fighting foam what three parts need to be inducted or injected in the correct ratios.
Foam concentrate
Water
Air.
Ch. 14 pg. 479 Definitions: Foam concentrate Foam Solution Foam
Foam Concentrate, Raw foam Liquid stored in totes before mixed with water or air.
Foam solution- mixture of foam concentrate and water before injected with air.
Foam- completed product after air is introduced into the foam solution (also called finished foam)
Ch. 14 pg. 481
Foam extinguishes and or suppresses vapors by the following methods: (3)
> 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.
Ch. 14 foam pg. 504
The nozzle that is limited to the application of Class A foam from a CAFS, provides an effective stream with excellent reach is what?
Smooth bore nozzle.
The exception to the standard rule that dictates the discharge orifice be no greater than half the diameter of the hose.
Ch. 14 foam pg. 482 Most fire fighting foam concentrates are formulated to mix with \_\_\_\_\_\_ to \_\_\_\_\_\_ percent water. A. 92-98.9% B. 93-99.9% C. 95-99.9% D. 94-99.9%
D. 94-99.9%
Ch. 14 pg. 483 What method of proportioning foam uses the pressure of a water steam to induct (draft) foam concentrate in the fire stream. A. induction B. Injection C.premixing D. batch mixing
A. Induction
Note: achieved by passing a stream of water through a venturi device called an eductor.
Ch. 14 pg. 480
Class B. fuels are divided into two categories:
hydrocarbons
polar solvents
Ch. 14 pg. 480
Class B foam is used on what kind of fuel?
Ineffective on what kind of fuel?
hydrocarbons
polar solvents
Ch. 14 pg. 480
Gasoline is considered a hydrocarbon. When mixed with ______ percent solvent additives, it should be treated as a polar solvent during emergency operations.
15%.
Ch. 14 pg 485 Depending on convenience foam solution maybe stored in a variety of containers. Under conditions that may require large quantities of foam such as aircraft rescue fire fighting, wildland, or industrial facilities which storage method would supply enough foam concentrate. A. Pail B. Barrels C. Totes D. apparatus tanks
C. Totes.
Tote carry 275 gallons.
Ch. 14 pg. 484 foam storage containers amounts pails barrels totes apparatus tanks
pails - 5 gallons
barrels - 55 gallons
totes - 275 gallons
apparatus tanks 20-200 gallons.
foam pumper or tender may carry 8000 gallons.
Ch. 14 foam storage
Class A foam storage life: pg. 487
Class B protein foam: 489
Class B synthetic foam: 489
class A. = 20 years Class B protein foam = 10 years Class B. synthetic foam = 20-25 years.
Regardless of the type of tank, foam storage must be airtight.
Class B foams should be stored in a cool area to maximize shelf life.
Ch. 14 pg. 486
Class A foam accepted use is for:
Class B foam accepted use is for:
ordinary combustibles
flammable liquids
Ch. 14 pg. 488
proportioning Class A foam for fire attack and overhaul with a standard fog nozzle: what percent concentrate is used?
0.2-0.5 % concentrate
Ch. 14 pg. 488. When using class A foam for exposure protection what is the correct percent of concentrate with a standard fog nozzle.
0.5-1.0 percent concentrate.
Ch. 14. 488
when applying Class A foam using a compressed air foam system what percent concentrate should be used?
0.2-0.5 percent concentrate
Ch. 14. pg 488 When applying class A foam using an air aspirating nozzle what percent concentrate should be used?
0.3-0.7 percent concentrate.
Ch. 14 pg. 490
Proportioning Class B foams: 1
Hydrocarbons : 2
Polar Solvents: 3
- one to six percent
- one or three percent
- three or six percent.
Ch. 14 pg. 493
Alcohol resistant AFFF concentrate: This concentrate can be used on both hydrocarbon fuels and polar solvents. While the proportioning needs to be adjusted for each. correct percent for:
hydrocarbon fuels:
polar solvent fuels:
hydrocarbons 1 to 6 %
polar solvents 3 or 6 %.
aspirating nozzles are generally best for preserving the membrane that forms on the surface of these products.
Ch. 14 pg. 495
The in-line eductor uses the Venturi principle to draft foam concentrate into the water stream. The pressure at the discharge side of the eductor must not exceed 70 percent of the eductor inlet pressure. Excessive back pressure may result in no foam concentrate being inducted into the water. Back pressure is determined by:
adding the nozzle pressure, friction loss in the hose between the eductor and the nozzle, and the elevation pressure.
ch.14 pg. 506 Under certain circumstances D/O may be required to operate a hand line or master stream during an incident at which foam lines are used. What is the correct application method for Class A foam? A. Rain down method B. Roll on method C. Bank down method D. Direct application.
D. direct application.
This technique follows the same procedure as direct attack using plain water, yet usually more effective due to Class A foams’s enhanced extinguishing capabilities.
Ch. 14 pg. 508
The primary concern regarding the environmental impact of foam is the effect of finished foam after application to a fire or spill. The process of decomposition results in:
A. rate at which bacteria can degrade the foam
B. the ratio of foam to the body of water
C. the consumption of oxygen
D. the severity of impact may vary based on the concentrate and type of Class A or B solution.
C. the consumption of oxygen.
ch. 14 pg. 508-509
Although used in the same manner as Class A foam, these agents are structurally and chemically quite different. Unlike Class A foam these form small bubbles filled with water.
durable agents.
Ch. 14. pg. 509
Durable agents:
When used as an extinguishing agent, the standard application rate is:
when used on a fire line the application rate:
Fore structure protection the application rate is:
1%
1.5-2%
2-3%
durable agents will adhere to vertical structural surfaces for up to 24 hours.
