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Questions and Answers
What should not exceed the rated capacity in gallons per minute through the eductor?
What should not exceed the rated capacity in gallons per minute through the eductor?
The flow
Which kind of nozzle inducts air into foam solution by a Venturi action and is the only nozzle that should be used with protein and fluoroprotein concentrates?
Which kind of nozzle inducts air into foam solution by a Venturi action and is the only nozzle that should be used with protein and fluoroprotein concentrates?
Batch mixing is generally only used with which types of foam concentrates?
Batch mixing is generally only used with which types of foam concentrates?
What is the percentage of Class A Foam?
What is the percentage of Class A Foam?
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What is the percentage of Class B foam?
What is the percentage of Class B foam?
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The minimum amount of foam solution that must be used on a fire per minute per square foot (square meter) of fire is called the:
The minimum amount of foam solution that must be used on a fire per minute per square foot (square meter) of fire is called the:
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Which of the following BEST explains why fuel and fire might consume a portion or the entire foam blanket?
Which of the following BEST explains why fuel and fire might consume a portion or the entire foam blanket?
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Installed in-line eductors are most commonly used to proportion which class of foam?
Installed in-line eductors are most commonly used to proportion which class of foam?
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Regardless of the type of tank, what is one characteristic that all foam storage containers share?
Regardless of the type of tank, what is one characteristic that all foam storage containers share?
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Driver/operators calculate the application rate available from a specific nozzle by:
Driver/operators calculate the application rate available from a specific nozzle by:
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For a portable foam application device, once foam concentrate and water have mixed to form a foam solution, the solution must be:
For a portable foam application device, once foam concentrate and water have mixed to form a foam solution, the solution must be:
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In which of the following situations is it acceptable to mix together different manufacturers' foam concentrates?
In which of the following situations is it acceptable to mix together different manufacturers' foam concentrates?
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Which proportioning method uses premeasured portions of water and foam concentrate that are mixed in a container?
Which proportioning method uses premeasured portions of water and foam concentrate that are mixed in a container?
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What is the smallest type of foam storage container?
What is the smallest type of foam storage container?
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In order to produce fire fighting foam, what three items must be educted or injected in correct ratios?
In order to produce fire fighting foam, what three items must be educted or injected in correct ratios?
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Which of the following factors is MOST likely to affect the degree of expansion in a foam solution?
Which of the following factors is MOST likely to affect the degree of expansion in a foam solution?
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Which of the following has a pickup tube that is located in the center bore of the nozzle and uses a modified Venturi design to draw concentrate into its water stream?
Which of the following has a pickup tube that is located in the center bore of the nozzle and uses a modified Venturi design to draw concentrate into its water stream?
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What are Mil-Spec concentrates?
What are Mil-Spec concentrates?
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Which of the following is the most common apparatus-mounted foam proportioner and consists of a small return (bypass) water line connected from the discharge side of the pump back to the intake side of the pump?
Which of the following is the most common apparatus-mounted foam proportioner and consists of a small return (bypass) water line connected from the discharge side of the pump back to the intake side of the pump?
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Which of the following is a disadvantage of durable agents?
Which of the following is a disadvantage of durable agents?
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The act of mixing water with foam concentrate to form a foam solution is called:
The act of mixing water with foam concentrate to form a foam solution is called:
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Low energy foam systems impart pressure on the foam solution with the use of the:
Low energy foam systems impart pressure on the foam solution with the use of the:
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Which of the following is true about the adequate and/or inadequate production of foam when an in-line proportioner is used?
Which of the following is true about the adequate and/or inadequate production of foam when an in-line proportioner is used?
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In some installed in-line eductor systems, a(an) ____ proportioner is installed to reduce the friction loss across the eductor.
In some installed in-line eductor systems, a(an) ____ proportioner is installed to reduce the friction loss across the eductor.
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Which method for Class B foam application involves directing the foam onto a vertical surface and allowing it to run down and spread across pooled fuel product?
Which method for Class B foam application involves directing the foam onto a vertical surface and allowing it to run down and spread across pooled fuel product?
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Which kind of nozzle allows firefighters the option of operating fixed flow, selective flow, or automatic flow when applying a low expansion, short duration foam blanket?
Which kind of nozzle allows firefighters the option of operating fixed flow, selective flow, or automatic flow when applying a low expansion, short duration foam blanket?
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What is the commonly used guideline for proportioning Class A foam for exposure protection with standard fog nozzles?
What is the commonly used guideline for proportioning Class A foam for exposure protection with standard fog nozzles?
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Which of the following is determined by the rate at which natural bacteria can degrade foam?
Which of the following is determined by the rate at which natural bacteria can degrade foam?
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What are the two basic types of medium- and high-expansion foam generators?
What are the two basic types of medium- and high-expansion foam generators?
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Which of the following are examples of polar solvent fuels requiring the use of special polymeric fire fighting foam?
Which of the following are examples of polar solvent fuels requiring the use of special polymeric fire fighting foam?
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The formula of Class A foam includes ____ that reduce the surface tension of water in the foam solution.
The formula of Class A foam includes ____ that reduce the surface tension of water in the foam solution.
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Which foam is MOST likely to be used to combat concealed space fires in cellars or other subterranean spaces?
Which foam is MOST likely to be used to combat concealed space fires in cellars or other subterranean spaces?
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Which of the following is an element that affects the breakdown process of Class A foam?
Which of the following is an element that affects the breakdown process of Class A foam?
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Due to the low eduction rates on a CAFS apparatus, what is required to supply the fire stream at the rate of 0.1 to 1.0 percent?
Due to the low eduction rates on a CAFS apparatus, what is required to supply the fire stream at the rate of 0.1 to 1.0 percent?
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Which of the following is released as fire fighting foam breaks down, providing a cooling effect on the fuel and suppressing the process of heat-producing oxidation?
Which of the following is released as fire fighting foam breaks down, providing a cooling effect on the fuel and suppressing the process of heat-producing oxidation?
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Both of the basic types of medium- and high-expansion foam generators produce foam containing:
Both of the basic types of medium- and high-expansion foam generators produce foam containing:
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In order to eliminate using pails or barrels to supply a foam eductor, fire apparatus equipped with onboard foam proportioning systems usually have ____ piped directly to the delivery system.
In order to eliminate using pails or barrels to supply a foam eductor, fire apparatus equipped with onboard foam proportioning systems usually have ____ piped directly to the delivery system.
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Class A foam solutions do not retain their foaming properties when mixed in water for more than:
Class A foam solutions do not retain their foaming properties when mixed in water for more than:
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Which of the following is a variable that affects a foam's rate of application?
Which of the following is a variable that affects a foam's rate of application?
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Direct application is a method of attack that is BEST used with:
Direct application is a method of attack that is BEST used with:
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Class B synthetic foam concentrate is made from:
Class B synthetic foam concentrate is made from:
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Which of the following are designed to work in conjunction with proportioners to produce the best possible foam?
Which of the following are designed to work in conjunction with proportioners to produce the best possible foam?
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Which of the following statements about variable-flow demand-type balanced pressure proportioners is MOST accurate?
Which of the following statements about variable-flow demand-type balanced pressure proportioners is MOST accurate?
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A type of in-line eductor that may be used to supply foam concentrate to a self-educting master stream foam nozzle is called a:
A type of in-line eductor that may be used to supply foam concentrate to a self-educting master stream foam nozzle is called a:
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The process of foam decomposition results in the consumption of:
The process of foam decomposition results in the consumption of:
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Which of the following is a common handline nozzle used for foam application?
Which of the following is a common handline nozzle used for foam application?
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Because it forms a rigid coating that adheres well and is slow to drain, the best consistency of Class A foam for vertical surfaces is:
Because it forms a rigid coating that adheres well and is slow to drain, the best consistency of Class A foam for vertical surfaces is:
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When using the batch mixing proportioning method, frothing can be avoided by:
When using the batch mixing proportioning method, frothing can be avoided by:
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Which of the following statements about regular protein foams is MOST accurate?
Which of the following statements about regular protein foams is MOST accurate?
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Which proportioning method uses an external pump to force foam concentrate into the fire stream at the proper ratio in comparison to the flow?
Which proportioning method uses an external pump to force foam concentrate into the fire stream at the proper ratio in comparison to the flow?
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Which foam consists of fluorochemical and hydrocarbon surfactants combined with solvents to create a high boiling point?
Which foam consists of fluorochemical and hydrocarbon surfactants combined with solvents to create a high boiling point?
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Which of the following is a proportioner used on large mobile apparatus installations, such as ARFF vehicles, and is one of the most accurate methods of foam proportioning?
Which of the following is a proportioner used on large mobile apparatus installations, such as ARFF vehicles, and is one of the most accurate methods of foam proportioning?
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Viscosity, or the thickness and ability of a liquid to flow freely, is MOST likely to be affected by:
Viscosity, or the thickness and ability of a liquid to flow freely, is MOST likely to be affected by:
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Which of the following is BEST described as the device that injects the correct amount of foam concentrate into the water stream to make the foam solution?
Which of the following is BEST described as the device that injects the correct amount of foam concentrate into the water stream to make the foam solution?
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In which of the following ways are durable agents similar to Class A foam?
In which of the following ways are durable agents similar to Class A foam?
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Which of the following is a limitation of CAFS?
Which of the following is a limitation of CAFS?
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High-energy foam generating systems/CAFS differ from other methods because:
High-energy foam generating systems/CAFS differ from other methods because:
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Which of the following is a basic foam proportioner that is designed to be attached directly to the pump panel discharge or connected at some point in the hose lay?
Which of the following is a basic foam proportioner that is designed to be attached directly to the pump panel discharge or connected at some point in the hose lay?
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A smooth bore nozzle is limited to the application of which classification of foam?
A smooth bore nozzle is limited to the application of which classification of foam?
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Which of the following statements about batch mixing is MOST accurate?
Which of the following statements about batch mixing is MOST accurate?
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Why is it important to avoid direct application of Class A foam to natural bodies of water?
Why is it important to avoid direct application of Class A foam to natural bodies of water?
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When operating an in-line foam eductor, which of the following operating guidelines must be followed to achieve properly proportioned finished foam?
When operating an in-line foam eductor, which of the following operating guidelines must be followed to achieve properly proportioned finished foam?
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Study Notes
Foam Application and Properties
- Application Rate: Minimum foam solution required is referred to as the application rate, which is determined per minute and per square foot (or meter) of fire area.
- Foam Blanket Consumption: Inconsistent application time can lead to consumption of a portion or all of the foam blanket by fuel and fire.
- Mixing with Water: Class A foam solutions lose foaming properties if mixed with water for over 24 hours.
Foam Proportioning and Storage
- Installed In-line Eductors: Primarily used for Class B foam.
- Foam Storage Containers: All foam storage tanks share the characteristic of being airtight to prevent contamination and degradation.
- Foam Concentrate: Essential components for producing firefighting foam include foam concentrate, water, and air.
Mixing Methods
- Premixing: Involves premeasured portions of foam concentrate and water mixed in a container.
- Batch Mixing: Can lead to frothing unless water is slowly circulated in the tank.
- Injection Method: Uses an external pump to accurately introduce foam concentrate into the water stream.
Foam Generators and Nozzles
- Foam Generators: Two basic types are water aspirating and mechanical blower generators, both producing foam with high-air content.
- Foam Nozzles: Fog nozzles offer flexibility for operating fixed, selective, or automatic flow, while air-aspirating nozzles are designed for use with protein and fluoroprotein concentrates.
Specific Foam Characteristics
- Biodegradability: Refers to the rate at which natural bacteria can degrade foam.
- Durable Agents: Although effective, they create slippery surfaces post-application, which may pose safety risks.
- Polar Solvent Fuels: Examples include alcohol and ketones, requiring specialized polymeric firefighting foam.
Class A and Class B Foams
- Class A Properties: Foam concentrate percentage for exposure protection typically ranges from 0.5 to 1.0 percent.
- Class B Properties: Made from fluorosurfactants; application rates can range from 1 to 6 percent based on the specific foam type and fire scenario.
System Limitations and Considerations
- CAFS Limitations: The system's hoses can exacerbate burst reactions due to compressed air while being effective at low eduction rates.
- Temperature Effects: Ambient air temperature affects the breakdown process of Class A foam and the viscosity of foam solutions.
Application Techniques and Situations
- Direct Application: Class A foam is best used with direct application methods for combating specific scenarios.
- Bank-down Method: Involves directing foam onto vertical surfaces for spreading across pooled fuel.
- Colloquial Feed Systems: Systems like the around-the-pump proportioner use small return water lines to balance water and foam concentrate.
Foam Types and Uses
- High-Expansion Foam: Preferred for concealed space fires due to its volume and ability to fill spaces effectively.
- Film Forming Fluoroprotein Foam (FFFP): Often used in situations requiring high efficiency and effectiveness.
Key Equipment and Performance
- Self-Educting Master Stream Foam Nozzle: Utilizes a modified Venturi design for concentrate integration.
- Variable-Flow Demand-Type Proportioners: Adjust foam concentrate based on demand while maintaining effective flow.
- Foam Proportioner: Essential device for injecting the correct amount of foam concentrate into the water stream.
Best Practices
- Quality Control: Ensure nozzle pressure is maintained for effective foam generation and delivery.
- Avoiding Environmental Harm: Direct application of Class A foam to natural water bodies should be carefully monitored to prevent ecological damage.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge with these flashcards covering crucial concepts from Chapter 14 about Foam Equipment and Systems. This quiz includes key terms like application rate and factors affecting foam effectiveness in fire suppression. Perfect for fire science students or professionals looking to refresh their understanding.
