Chapter 16 —Fire Streams—
As water is vaporized into steam, it expands approximately __________ its original volume.
1,700 times
Which statement describes a fog stream?
A fine spray composed of tiny water droplets
How does the nozzle setting and the stream pattern affect water's ability to suppress fire?
A stream broken into small droplets absorbs heat more rapidly because of greater surface area.
What is the primary way in which water extinguishes fire?
Absorbing heat
Which foams are required to extinguish fires of ethanol or ethanol-based fuels?
Alcohol-resistant foams
What are installed in-line eductors, around-the-pump proportioners, and balanced pressure proportioners examples of?
Apparatus-mounted proportioners
Which type of nozzle control valve if partially opened on a smooth bore nozzle may cause turbulence and affect the fire stream?
Ball valve
Because the foam solution goes through the pump, which proportioning method may cause the pump to require additional maintenance?
Batch-mixing
Which proportioning method may make it difficult to refill an apparatus water tank due to excessive bubbling from residual foam solution?
Batch-mixing
Which stream pattern is used to extinguish fires in attics, cocklofts, basements, and other confined spaces?
Broken stream
In which type of fire situation are high-expansion foams typically used?
Confined spaces such as mines and shipboard compartments
Which type of fog nozzle provides a constant discharge rate throughout a range of patterns?
Constant gallonage
Which best describes a use of a fire stream?
Dispersing hot smoke and fire gases from a heated area
True or False: Foam concentrates generate bubbles through a chemical reaction when concentrates are mixed with water.
False
True or False: Nozzles should be stored with the control valve bale in the open position.
False
When using an in-line eductor, which situation might cause foam concentrations to be too lean?
Foam concentrate inlet too far above surface of foam concentrate
Which fire stream pattern can be used for hydraulic ventilation?
Fog stream
Which is the most common type of foam proportion used in the fire service?
In-line foam eductor
What can be done to help overcome friction loss?
Increasing pump pressure
While fighting a Class B fire, you notice that the foam solution has become too lean. You notice that the liquid level of the foam concentrate is approximately 7 ft. (2.13 m) below the eductor. What can be done to improve the quality of the foam solution?
Lower the eductor by at least 1 ft. (0.3 m)
Which type of fire stream is created by apparatus-mounted appliances?
Master stream
Which foam generator is typically associated with total-flooding applications?
Mechanical blower generator
Which classification of foam is used to suppress vapors from hazardous materials spills?
Medium-expansion foam
Which situation commonly produces poor-quality foam?
Mixing different types of foam concentrate in the same tank
Which type of nozzle can be used to effectively control fires in concealed spaces?
Piercing
Which term refers to liquids that mix readily with water?
Polar solvents
Which type of foam(s) may be used with air-aspirating nozzles?
Protein and flouoroprotein concentrates
Which is the primary manual application technique used on aboveground storage tank fires?
Rain-down method
Which situation commonly produces poor-quality foam?
Restricted water flow
Which type of nozzle control valve controls the discharge pattern of the fire stream?
Rotary control valve
Which type of nozzle control valve seats a movable cylinder against a shaped cone in order to terminate water flow?
Slide valve
Which nozzle produces a compact stream with little shower or spray?
Smooth bore nozzle
Which fire stream pattern has the ability to reach areas that other streams cannot?
Solid stream
Which factor plays a role in defining the specific fire stream patterns?
The volume of water flowing from the nozzle per minute
How may gravity, friction of air, and wind effect a solid fire stream?
They may decrease the reach of the stream.
Which characteristic is associated with the fog patterns produced by low-flow fog nozzles?
They produce lower-density fog patterns
When operating a handline, why should a firefighter open the control valve slowly?
To better control nozzle reaction
True or False: For maximum effectiveness, foam concentrates must be proportioned at the specific percentage for which they were designed.
True
True or False: Rotary control valves control both the water flow and the discharge pattern of a fire stream.
True
True or False: To prevent water hammer, valves, nozzles, and hydrants should be closed slowly.
True
True or False: When applying foam to a pool of liquid fuel, the operator continues to apply foam until it spreads across the entire surface of the fuel.
True
Which foam generator produces foam by pumping foam solution through the nozzle in a fine spray?
Water-aspirating type nozzle
Which variable will influence the application rate of the foam concentrate used on a hydrocarbon or polar solvent fuel?
Whether the fuel is spilled or on fire