Questions and Answers
Which extinguishment method involves foam creating a barrier between the fuel gases and any possible ignition sources?
Separating
Class B foams are especially effective on:
hydrocarbon fuels
In order to create high-quality foam:
foam concentrate, water, and air must be mixed in the correct ratio
High-quality foam bubbles are created through the process of:
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The amount that fire fighting foam expands depends on the type of foam concentrate used and:
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Class A foam acts as a surfactant, which means that it:
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Polar solvent fuels are flammable liquids that mix readily with water.
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The rate of application for Class B foam depends on:
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What is necessary when applying fire fighting foam?
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Because of environmental concerns about fire fighting foam, firefighters should:
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Mixing water with foam concentrate to form a foam solution is referred to as:
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Most fire fighting foams are intended to be mixed with:
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Which factor is important when selecting the appropriate foam proportioner to use?
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Which method of foam proportioning involves using an external pump to force foam concentrate into the fire stream?
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The premixing method of foam proportioning is typically used with:
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Which type of foam proportioner is directly attached to the pump panel outlet or connected at some point in the hose lay?
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Which type of foam proportioner can compromise firefighter safety by slowing down operations since it requires the concentrate to be available where the nozzle is being operated?
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A(An) _____ is mounted on an apparatus and uses a centrifugal pump to supply the water for the foam solution and an onboard air compressor to add air to the mixture before discharge.
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Fog nozzles can be used with foam solution to produce:
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An advantage of _____ is that they are widely available on most fire apparatus.
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Which is a characteristic of foam nozzles?
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What is an advantage of using a foam nozzle to apply fire fighting foam?
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If the foam being produced is poor quality, the firefighter should:
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What is likely to cause poor quality fire fighting foam to be produced?
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Which method of foam application is only suitable for use on a pool of liquid fuel on open ground?
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Which method of foam application would be well suited for a flammable liquid spill near the exterior wall of a building?
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If a large pool of flammable liquid is burning in an open area, the _____ method of foam application may be the most effective method to use.
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What should firefighters do if the fire begins to spread uncontrollably when they are applying foam?
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Which type of substances have a flash point less than 100°F (38°C)?
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Which statement accurately describes pressurized vessels?
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Study Notes
Foam Fire Fighting Concepts
- Separating Method: Foam creates a barrier between fuel gases and ignition sources to extinguish fires.
- Class B Foams: Specifically effective on hydrocarbon fuels, such as gasoline and oil.
- High-Quality Foam Creation: Requires correct mixing ratios of foam concentrate, water, and air.
- Aeration: The process that generates high-quality foam bubbles.
Foam Application and Effects
- Foam Expansion Factors: Depends on the type of foam concentrate and the accurate proportioning of the solution.
- Class A Foam Functionality: Acts as a surfactant, lowering water's surface tension for better penetration into fuels.
- Polar Solvent Fuels: Flammable liquids that mix readily with water, complicating firefighting efforts.
- Class B Foam Application Rate: Varies based on whether the fuel is contained or spilled.
Application Techniques and Environmental Considerations
- Continuous Application: Essential for complete extinguishment when using firefighting foam.
- Environmental Precautions: Firefighters should prevent foam from entering bodies of water due to ecological concerns.
- Proportioning Definition: Mixing water with foam concentrate to form a solution.
Foam System and Proportioning Types
- Water-to-Foam Ratio: Most fire fighting foams are mixed with 94 to 99.9 percent water.
- Foam Proportioner Consideration: The appropriate proportioner selection is influenced by available water pressure.
- Injection Method: Involves an external pump forcing foam concentrate into the fire stream.
- Premixing Method: Commonly used with vehicle-mounted tank systems.
Foam Proportioner Types and Nozzle Characteristics
- In-line Eductor: Attached directly to the pump panel outlet or hose lay.
- Foam Nozzle Eductor: Can compromise safety as it requires concentrate at the nozzle's operation point.
- Compressed Air Foam System (CAFS): Uses a centrifugal pump and onboard air compressor for foam solution discharge.
Foam Application Techniques
- Fog Nozzles with Foam: Produce low-expansion, short-lasting foam and are widely available.
- Foam Nozzle Advantages: Produce higher quality foam compared to fog nozzles, although they have a shorter stream reach.
- Poor Quality Foam: Check for air leaks in the proportioning device if foam quality is low.
- Concentrate Mixing Issues: Mixing different foam concentrates in the same tank can lead to poor foam quality.
Specific Foam Application Methods
- Roll-on Method: Suitable for liquid fuel pools on open ground.
- Bank-down Method: Effective for flammable liquid spills near building exteriors.
- Rain-down Method: Most effective for large burning liquid pools in open areas.
- Retreat Protocol: Firefighters should retreat to safety and use handlines for protection if fires spread uncontrollably.
Fire and Substance Classifications
- Flammable Liquids: Defined as substances with a flash point below 100°F (38°C).
- Pressurized Vessels: Must be marked with placards or stickers indicating their contents for safety and awareness.
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Description
Test your knowledge on foam fire fighting methods, particularly for liquid and gas fires, with this engaging flashcard quiz. Discover key terms and definitions related to extinguishment techniques and the effectiveness of various foam types. Perfect for students and professionals in fire safety and emergency response.