Chpt 14 Flashcards
1
Q
The national institute of standards and technology has determined that foam is ______ more effective than plain water in extinguishing fires, which can justify its use and added expense at an incident site
A
Three to five times
2
Q
Is a device that mixes the foam concentrate into the fire stream in the proper percentage
A
Foam proportioner
3
Q
The expansion of foam solution depends on good mechanical agitation and effective ______, the process of introducing air into the foam solution
A
Aeration
4
Q
Foam tetrahedron includes four components
A
Water
Foam concentrate
Air
Mechanical agitation
5
Q
Are produced when water and foam concentrate are mixed in the appropriate amounts
A
Mechanical foams
6
Q
Hydrocarbon fuels, such as gasoline, jet fuel, and kerosene, have a lower _______ than water
A
Surface tension
7
Q
Comprises the time required for a foam blanket to spread out across a fuel surface
A
Knockdown and speed flow
8
Q
Are used on ordinary combustible materials such as wood, textiles, and paper; they are also effective on organic materials such as straw and hay.
A
Class A
9
Q
Class A foams sometimes referred to as ______, are very effective because they improve the penetrating effect of water and allow for great heat absorption
A
Wetting agents
10
Q
According to foam manufacturers, these wetting agents can extinguish fie involving class A materials as much as _____ faster than water
A
20 times
11
Q
Is particularly useful for protecting buildings in rural areas during forest and brush fires when the water supply is limited
A
Class A foam
12
Q
Many fire departments use ____ while performing initial attack and overhaul of fires
A
Class A foam
13
Q
Class A foam increases the effectiveness of the water as an extinguishing agent by reducing the _____ of the water
A
Surface tension
14
Q
Are used on hydrocarbon, combustible fuels, or polar solvent fires
A
Class B foams
15
Q
A _____ reduces the surface tension of water and enhances penetration into fuel that is burning
A
Wetting agent
16
Q
A ____ creates a stable mass of small, air filled bubbles with lower density than oil, gas, or water and will float on top of burning fuel, creating a blanket that separates the fuel from air, lowering the Temperature and suppressing the vapors
A
Foam
17
Q
Are used to extinguish class B fires involving hydrocarbons
A
Protein foams
18
Q
Contain naturally occurring proteins that is, animal by product as the foaming agent.
A
Protein foams
19
Q
They produce highly stabilized mechanical foam with good expansion properties, excellent heat, and ______ and good drainage characteristics
A
Burn back resistance
20
Q
Consists of hydrolyzed protein, stabilizers, preservatives, and synthetic fluorocarbon surfactants
A
Fluoroprotein foam
21
Q
This type of foam is used for hydrocarbon vapor suppression and extinguishment of fuel in depth fires
A
Fluoroprotein foam
22
Q
Have slower knockdown characteristics than other concentrates, but they provide a long lasting foam blanket after the fire is extinguished
A
Regular protein foams
23
Q
Because they must be properly aspirated, these foams should not be used with non aspirating structural fog nozzles
A
Fluoroprotein foams
24
Q
Is able to form a vapor sealing film on non polar solvents
A
Film forming fluoroprotein foam
25
Knockdown performance is improved because the foam releases an aqueous film on the surface of the hydrocarbon fuel
Film forming fluoroprotein foams
26
Can be used on both hydrocarbon and water soluble fuels
Alcohol resistant film forming fluoroprotein foam
27
AR-FFFP is basically FFFP with a _______ additive
Polysaccharide polymer additive
28
Is based on combination of flurochemical surfactants, hydrocarbon surfactants, mad solvents
AFFF aqueous film forming foam
29
Because of the versatility of ____; it is used by the majority of municipal and airport fire departments in North America
AFFF
30
It’s ability to flow quickly allows _____ to achieve a very fast knockdown of hydrocarbon fuels
AFFF
31
Aspirating foam nozzles Should be used to apply _____ to ensure maximum performance
AFFF
32
Comprises a combination of synthetic detergents, flurochemicals, and high molecular weight polymers
Alcohol resistant aqueous film forming foams
AR-AFFF
33
Is one of the most versatile type of foam.
AR -AFFF
34
Are highly effective in confined space firefighting operations and in areas where access is limited or entry is dangerous to fire fighters, such as basements, ship board compartments, warehouses, aircraft hangars, and mine shafts
High expansion foams
35
High expansion foams can be used on either ____ fires
Class a or class b fires
36
The foam concentrates are normally proportioned in rations between 1 to 3 percent for these uses
High expansion foams
37
Are designed to be mixed with water at specific ratios
Foam concentrates
38
Foam concentrate ratios vary from _____ for class a foams
0.1 to 1 percent
39
Foam concentrate ratio for class b
1 to 6 percent
40
Alcohol resistant foams can be used effectively on both hydrocarbon and polar solvent fuels. ______ is the most commonly used concentrate for this purpose; it is available in a variety of percentages
AR-AFFF
41
The _____ is the ratio of finished foam to foam solution after the concentrate is mixed with water, agitated, and aspirated through a foam making appliance
Foam expansion rate
42
Low expansion foam Has a foam expansion ratio of up to
20:1
43
This type of foam is primarily designed for use on flammable and combustible liquids
Low expansion foam
44
Low expansion foam is effective in controlling and extinguishing most
Class B fires
45
Medium expansion foam has a foam expansion ratio in the range of _______
20:1 to 200:1
46
This kind of foam is used primarily to suppress vapors from hazardous chemicals
Medium expansion foam
47
Foams with expansion ratios between ______ have been found to produce the optimal foam blanket for vapor mitigation of highly reactive chemicals and low boiling points
30:1 and 55:1 medium expansion foam
48
High expansion foams has a foam expansion ratio in the range of
200:1 to 1000:1
49
This type of foam is designed for confined space firefighting
High expansion foams
50
The foam concentrate consists of a synthetic, detergent type foam used in confined spaces such as basements, mines, ship board, and aircraft hangars
High expansion foams
51
The ____ is a device that mixes the foam concentrate into the fire steam in the proper percentage
Foam proportioner
52
Is the process of pouring foam concentrate directly into the fire apparatus water tank, thereby mixing a large amount of foam at one time
Batch mixing
53
Class a foams concentrates that are batch mixed must be used within ____ if they are to be effective
24 hours
54
Premixing of foam solutions is a technique that is usually reserved for
Portable fire extinguishers
55
Involves the use of an eductor to introduce the appropriate amount of foam concentrate into a stream of water flowing from a discharge
Induction
56
An ____ is an appliance that uses the Venturi principle to introduce foam concentrate into the water stream
Eductor
57
A ___ is usually designed to work at a predetermined pressure and flow rate; it’s metering valve can be adjusted to set the percentage of foam concentrate that is educted into the stream
Foam eductor
58
In line eductors should only be used for the application of
Foam
59
Those mounted to permanently to the fire pump are dedicated to one foam discharge; such as ____ are in line devices dedicated to producing foam only
Pump mounted eductors
60
Are permanently mounted appliances that can be used for water or foam application, depending on what is required at the incident scene
By pass eductors
61
Eductors use the ____ to mix a specific amount of foam concentrate into the water stream
Venturi principle
62
Foam concentrate is introduced into the eductor using a ____ which allows the driver operator to adjust the percentage of foam concentrate being added to the water system
Metering valve
63
An eductor inlet pressure of _____ is necessary to overcome friction loss through the eductor as well as the friction loss between the eductor and the nozzle
200 psi
64
The ____ controls the flow of concentrate into the eductor
Metering device
65
The amount of foam concentrate introduced into the water stream is controlled by adjusting the _____
Metering valve
66
Metering valves have adjustable settings that range from
0 closed position to 6 percent
67
The percentage set on the metering valve will be achieved only if the inlet pressure at the eductor matches the manufacturers recommend
Inlet pressure
68
An ______ is attached to the hoseline no more than 150 ft from the nozzle and no more than 6ft above the surface of the foam concentrate— a placement that makes it easy to set up and take down
In line eductor
69
This system uses a diaphragm type pressure control valve to sense and balance the pressures in the foam concentrate and water lines to the proportioner
Balanced pressure systems
70
Is a device required for each foam outlet to proportion the correct amount of foam concentrate into water stream over a wide range of flows and with minimal pressure loss
Ratio controller
71
A _____ at the pump panel allows the driver operator to monitor the foam concentrate and water pressures
Duplex gauge
72
A ____ located at the pump panel enables the driver operator to override the automatic system by increasing or decreasing foam concentrate pressure, in case a problem occurs within the system
Manual throttling control
73
The ____ uses water as its cooling source and prevents the foam concentrate from overheating
Heat exchanger
74
Use an electrically operated, variable speed foam concentrate pump that directly injects foam concentrate into the discharge side of the pump manifold
Injection systems
75
Are the most common type of system in use today and are designed for use in class A foam concentrates and with many class B concentrates, depending on the viscosity of the concentrate
Injection systems
76
With____ the driver operator can adjust the foam concentrate percentage while the system is in operation
Injection systems
77
Concentrate injection rates can be set anywhere in the range of 0.1 to 10 percent. These percentages, can be changed in ______, are selected using a button on the control unit.
0.1 percent increments
78
Combines compressed air and a foam solution to create the finished foam
CAFS combined air foam systems
79
This type of system is generally used to generate class A foam specifically, to create a high quality finished foam that clings to vertical surfaces
CAFS combined air foam systems
80
CAFS hoselines are typically filled with approximately____ compressed air
30 percent
81
Because the hose is filled with air, ______ is insignificant
Friction loss
CAFS
82
Produce medium and high expansion foams
Foam generators
83
A _____ aspirating type of generator uses a water motor driven fan to produce the required air flow
Water powered aspirating generator
84
Mechanical generators operate similarly to a water aspirating generator. The difference is that the mechanical generator is______, which forces air flow through the unit
Electrically powered by a fan
85
A ____draws the foam into the master stream nozzle, this tube is placed into the foam concentrate supply and operated as an eductor system
Pick up tube
86
Are designed to mix air with the foam solution as it is discharged
Air aspirating foam nozzle
87
Are the nozzle of choice when using CAFS
Smooth bore nozzles
88
Not aeration is the major concern when a smooth bore nozzle is used with CAFS
Application
89
Foam concentrate is stored in containers that range in size from
5 gal pails to 55 gallon drums
90
Totes and trailers of foam concentrate are available in different sizes as well ranging from _____ of foam concentrate
100 to 1000 gallons
91
Typical protein concentrate has a shelf life in the range of
7 to 10 years
92
Synthetic concentrates and high expansion concentrates have a shelf life of
20 to 25 years
93
Should be used only on a pool of flammable product that is located on open ground
Sweep roll method
94
Is employed at fires where the fire fighter can use an object to deflect the foam stream and let it flow down the burning surface
Bankshot bank down method
95
Can be used when there is no vertical object to use for a bank shot and it would be to dangerously get close and use a roll on method of foam application.
Rain down method
96
This foam application technique consists of lofting the foam stream into the air above the material and letting it fall down onto the surface
Rain down method
97
The maximum inlet pressure to the water pump cannot be more than
10 psi
98
The _____ used for firefighting purposes is a stable mass of small, air filled bubbles.
Foam
99
Foam Is created through the application of four components:
Water, foam concentrate, mechanical agitation, and air
100
Foams come into two basic types
Chemical and mechanical foams
101
Fuel resistance is foams ability to minimize ______, which is the absorption of the burning fuel into the foam itself.
Fuel pick up
102
Firefighting foams are classified as either
Class A or class B
103
Many fire departments use _____ while performing initial attack and overhaul of fires.
Class A
104
A _____ is a chemical compound that contains the elements carbon and hydrogen
Hydrocarbon
105
Class b foams are divided into the following categories
Protein foams
Fluroprotien foams
Alcohol resistant film forming fluoroprotien foam
AR-FFFP
106
Protein foams also include stabilizers and inhibitors, which prevent corrosion and control _____.
Viscosity
107
These foams must be properly aspirated, however; thus they should not be used with non aspirating structural fog nozzles
Protein foams
108
Notably, _____ is effective for subsurface application to hydrocarbon fuel storage
FP fluoroprotien foam
109
With these foams, the fluorochemical surfactants are generally present in higher concentrations than in standard FP
Film forming fluoroprotien foam FFFP
110
On hydrocarbon fires, the film forming ability of this foam allows for a rapid fire knockdown and excellent burn back resistance.
Alcohol resistant film forming fluoroprotien foam ARFFFP
111
It extinguishes fire by forming an aqueous film on the fuel surface
AFFF
112
When applied to polar solvents, however, ______ forms a ploymeric membrane on the fuel surface
AR-AFFF
113
Foams based on combinations of hydrocarbon surfactants and solvents
High expansion foams
114
They are useful of fuels such as liquified natural gas for vapor dispersion and control.
High expansion foams
115
In certain concentrations, these foams are effective extinguishing agents for flammable liquid spill fires of most types
High expansion foams
116
Have a tremendous smothering and steam generation effect because the water contained in them is divided into such fine particles, which enhances the heat absorption quality of water.
High expansion foams
117
When using class A foam for initial fire attack on a vehicle fire, you might use a ______ percent ratio of foam concentrate to water
0.3 to 0.5
118
If you were supplying a hoseline that was spraying foam on a house to protect it during a brush fire, you might increase the ratio to ______, thereby creating a thicker foam that would last longer and protect the house for extended period
3 percent
119
If the water tank on the fire apparatus holds 500 gallons of water and you want to use class A foam at 1 percent, you would add ______ of foam concentrate with an in line eductor
5 gallons of foam
120
As the water travels through the in line eductor, it draws foam concentrate into the water at a desired percentage using the
Venturi principle
121
Two types of eductors in use today
In line eductors and bypass eductors
122
Most eductors are calibrated to flow the rated capacity at _____ inlet pressure
200 psi
123
This kind of system uses a fire pump, foam concentrate injection system, and an air compressor to produce high quality finished foam streams inside the fire apparatus piping
CAFS
124
Some water powered high expansion generators are designed to achieve expansion rates of as much as _______ gal of finished foam for every 1 gal of foam solution
1000 gallons
125
High expansion foam systems are designed for use in total flooding applications and are effective at the following locations
Mines Machinery spaces
Warehouses. Hazardous waste facilities
Aircraft hangars Wildland fire breaks
Basements
Storage buildings
Paper warehouses
