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Questions and Answers
What is the primary use of Class B foam?
What is the primary use of Class B foam?
Which foam type is NOT allowed during training evolutions?
Which foam type is NOT allowed during training evolutions?
How much water is needed to simulate finished foam using the suggested mixture?
How much water is needed to simulate finished foam using the suggested mixture?
What is a requirement for combining AR-AFFF with regular AFFF?
What is a requirement for combining AR-AFFF with regular AFFF?
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What properties are characteristic of Aqueous Film Forming Foam (AFFF)?
What properties are characteristic of Aqueous Film Forming Foam (AFFF)?
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What is the minimum percentage of AFFF that should be utilized in operations?
What is the minimum percentage of AFFF that should be utilized in operations?
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Which foam is indicated for use with polar solvent-based fuels?
Which foam is indicated for use with polar solvent-based fuels?
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What does the batch mixing process involve?
What does the batch mixing process involve?
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What is the maximum distance from a hydrant within which an ARFF vehicle can directly receive water without additional apparatus?
What is the maximum distance from a hydrant within which an ARFF vehicle can directly receive water without additional apparatus?
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Which component does the ARFF foam supply resource pump directly to during operation?
Which component does the ARFF foam supply resource pump directly to during operation?
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Who is responsible for operating the aerial master stream during the firefighting operation?
Who is responsible for operating the aerial master stream during the firefighting operation?
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What type of nozzle should be attached to the aerial for effective operation?
What type of nozzle should be attached to the aerial for effective operation?
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Which hose size is required for supplying foam to the rear aerial inlet?
Which hose size is required for supplying foam to the rear aerial inlet?
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What is the primary function of Class A foam in firefighting?
What is the primary function of Class A foam in firefighting?
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Which statement regarding the application of Class B foam is true?
Which statement regarding the application of Class B foam is true?
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At what percentage should Class A foam be proportioned for effective firefighting?
At what percentage should Class A foam be proportioned for effective firefighting?
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What should be avoided when using Class B foam according to the provided procedures?
What should be avoided when using Class B foam according to the provided procedures?
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What is the potential consequence of mixing different types of foam concentrates?
What is the potential consequence of mixing different types of foam concentrates?
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What is the primary role of the Driver/Operator (D/O) during foam operations?
What is the primary role of the Driver/Operator (D/O) during foam operations?
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What does the Critical Flow Rate refer to in fire suppression?
What does the Critical Flow Rate refer to in fire suppression?
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Under what condition should foam operations be delayed?
Under what condition should foam operations be delayed?
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How should liquid soap be utilized in firefighting?
How should liquid soap be utilized in firefighting?
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Which type of foam is typically used for alcohol-related fires?
Which type of foam is typically used for alcohol-related fires?
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What is the foam solution made of?
What is the foam solution made of?
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Which position is responsible for overseeing foam operations?
Which position is responsible for overseeing foam operations?
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When utilizing a portable standpipe, what is crucial to ensure?
When utilizing a portable standpipe, what is crucial to ensure?
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What causes foam blankets to lose effectiveness on boiling fuel?
What causes foam blankets to lose effectiveness on boiling fuel?
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What is the maximum recommended length of 1-¾” hose to avoid significant foam quality reduction?
What is the maximum recommended length of 1-¾” hose to avoid significant foam quality reduction?
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To ensure proper foam proportioning, what is the effect of pumping less than 200 psi to the eductor inlet?
To ensure proper foam proportioning, what is the effect of pumping less than 200 psi to the eductor inlet?
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For extinguishing hydrocarbon spills, what initial proportion should be set on the proportioner?
For extinguishing hydrocarbon spills, what initial proportion should be set on the proportioner?
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What is the critical flow rate formula for hydrocarbons?
What is the critical flow rate formula for hydrocarbons?
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The Elkhart Chief 4000-14 fog nozzle operates at what flow rate?
The Elkhart Chief 4000-14 fog nozzle operates at what flow rate?
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Why must ARFF units be supplied with a continuous supply of water?
Why must ARFF units be supplied with a continuous supply of water?
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What happens to the foam stream when using lower-rated fog nozzles with the eductor?
What happens to the foam stream when using lower-rated fog nozzles with the eductor?
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What should be done if lower explosive limits (LEL) are detected when using foam blankets?
What should be done if lower explosive limits (LEL) are detected when using foam blankets?
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What is the recommended height limit for the foam concentrate level to the eductor?
What is the recommended height limit for the foam concentrate level to the eductor?
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What is the effect of using ethanol additives in a hydrocarbon during foam application?
What is the effect of using ethanol additives in a hydrocarbon during foam application?
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Which of the following units has different eductors and foam nozzles than the rest of Operations?
Which of the following units has different eductors and foam nozzles than the rest of Operations?
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What is the flow time range for foam application during firefighting?
What is the flow time range for foam application during firefighting?
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Which capability is unique to ARFF apparatus compared to other units?
Which capability is unique to ARFF apparatus compared to other units?
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What is the critical flow rate formula for polar solvents?
What is the critical flow rate formula for polar solvents?
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How many pails of foam should be available per 1-¾” foam line when extinguishing an ignited polar solvent?
How many pails of foam should be available per 1-¾” foam line when extinguishing an ignited polar solvent?
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In the event of batch mixing, what percentage should be used to calculate the required concentrate gallons in a 500-gallon tank for 3% foam?
In the event of batch mixing, what percentage should be used to calculate the required concentrate gallons in a 500-gallon tank for 3% foam?
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What is the consequence of not properly flushing the system after using AFFF foam during a fire operation?
What is the consequence of not properly flushing the system after using AFFF foam during a fire operation?
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Which foam application method aims to spread the foam blanket by directing the stream at the ground from the perimeter of the spill?
Which foam application method aims to spread the foam blanket by directing the stream at the ground from the perimeter of the spill?
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What is the maximum length of 1-¾” foam line that can be used without additional hose?
What is the maximum length of 1-¾” foam line that can be used without additional hose?
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Which of the following is a common reason for poor-quality foam blankets?
Which of the following is a common reason for poor-quality foam blankets?
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What is the recommended method to minimize trip hazards when walking on foam blankets?
What is the recommended method to minimize trip hazards when walking on foam blankets?
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When performing a batch mix for 6% foam in a 750-gallon tank, how many gallons of concentrate are needed?
When performing a batch mix for 6% foam in a 750-gallon tank, how many gallons of concentrate are needed?
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What must be the eductor pressure for effective foam application?
What must be the eductor pressure for effective foam application?
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What is a critical factor to check prior to inserting the pick-up tube into the open containers?
What is a critical factor to check prior to inserting the pick-up tube into the open containers?
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Which foam application method gently applies foam over the spill from above aiming at a 30-degree angle?
Which foam application method gently applies foam over the spill from above aiming at a 30-degree angle?
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What immediate action must be performed following a batch mix operation with foam?
What immediate action must be performed following a batch mix operation with foam?
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Which method requires the nozzle to be aimed parallel to the surface of the fuel without plunging into it?
Which method requires the nozzle to be aimed parallel to the surface of the fuel without plunging into it?
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What should be the maximum distance from the nozzle to the eductor when using the AWG S4/M4 low/medium expansion foam nozzle?
What should be the maximum distance from the nozzle to the eductor when using the AWG S4/M4 low/medium expansion foam nozzle?
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How can improperly working eductors be temporarily repaired?
How can improperly working eductors be temporarily repaired?
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What is the recommended solution if air leaks occur around the pick-up tube attachment to the eductor?
What is the recommended solution if air leaks occur around the pick-up tube attachment to the eductor?
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What is the priority action after every use of an eductor assembly?
What is the priority action after every use of an eductor assembly?
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At what pressure must the eductor backflush button not be forced?
At what pressure must the eductor backflush button not be forced?
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What should be confirmed before inserting the pick-up tube into the foam containers?
What should be confirmed before inserting the pick-up tube into the foam containers?
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Which component is replaced with a 2-½” x 1-½” reducer during the aerial foam evolution?
Which component is replaced with a 2-½” x 1-½” reducer during the aerial foam evolution?
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What is a temporary fix for a foam blanket that appears watery during application?
What is a temporary fix for a foam blanket that appears watery during application?
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What flow rate is the Chief model #4000-14 fog nozzle rated for?
What flow rate is the Chief model #4000-14 fog nozzle rated for?
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What action should be taken if the pump panel is receiving water from a pressurized source during flushing?
What action should be taken if the pump panel is receiving water from a pressurized source during flushing?
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Which of the following must be done to the hoseline during the flushing process?
Which of the following must be done to the hoseline during the flushing process?
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Which accessory should be used when connecting the in-line foam eductor to the pump panel for a 250 GPM flow rate?
Which accessory should be used when connecting the in-line foam eductor to the pump panel for a 250 GPM flow rate?
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How should the pressure at the eductor be monitored during the flushing process?
How should the pressure at the eductor be monitored during the flushing process?
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Study Notes
Foam Types and Usage
- Class A foam is effective for ordinary combustibles, enhancing water penetration for fires like tire, vehicle, and wildland fires.
- Class B foam extinguishes flammable liquid fires by vapor suppression and cooling.
- Foam application training must exclude Class A FireAde and Class B AR-AFFF due to health concerns.
- Finished foam can be made from a mix of five gallons of water and three cups of car wash.
Foam Definitions
- Alcohol Resistant Aqueous Film Forming Foam (AR-AFFF) is used with polar solvents at a concentration of 6%.
- Aqueous Film Forming Foam (AFFF) is a detergent-based foam compatible with dry chemical agents, known for rapid extinction and self-healing characteristics.
- Finished foam comprises a mixture of foam concentrate, water, and air.
Operational Procedures for Class A Foam
- Utilize Class A foam for better penetration and quicker extinguishment over plain water on various fire types.
- Ensure apparatus foam tanks are filled with Class A foam concentrate; do not mix with Class B foam.
- Class A foam should be proportioned between 0.5% and 1.0%.
- Liquid soap can act as a basic substitute for Class A foam.
Class B Foam Application
- Class B foam works by separating fuel from air, cooling it, and suppressing vapors.
- Majority of foam generation occurs through induction or batch mixing.
- Operations typically employ 3% to 6% AR-AFFF sourced in 5-gallon buckets.
- Proper foam volume must be available before beginning a foam operation; prioritize exposure protection otherwise.
Equipment and Resources
- Onboard Class B systems must not mix Class A foam; familiarize with each unit's system.
- Suppression units are equipped with specific foam generating equipment, like Elkhart and TFT in-line eductors.
- ARFF units focus on regular AFFF, carrying high foam output capacities with various supplier options available.
Application Hydraulics and Techniques
- An in-line foam eductor requires a pump pressure of 200 psi at its inlet, adjusted for hose lengths and elevation.
- Maintain foam concentrate at a maximum height of 6 feet from the eductor.
- For ignited spills, proper flow rates and durations are essential, with different formulas depending on fuel types (hydrocarbon vs. polar solvent).
Foam Application Methods
- Employ methods such as roll-on, bank-down, rain-drop, and seat-of-the-fire for effective foam application.
- Minimize walking on foam blankets and use careful foot placement if necessary.
Common Issues and Solutions
- Avoid foam quality issues by ensuring proper nozzle operation, correct eductor pressure, and unclogged systems.
- Address excessive hose length by limiting configurations to standard lengths; maintain the integrity of foam lines to ensure effective application.### Eductor Ball Check Valve Maintenance
- Shut down pump discharge gates when possible to prevent damage during maintenance.
- For a stuck eductor ball, gently tap with a rubber mallet or release the ball using a screwdriver.
- Replace plastic clamps on the pick-up tube attachment with metal ones to prevent air leaks.
- After each use, disassemble the eductor assembly and wash the ball check valve with warm water to avoid sticking.
Foam Application Issues
- Watery foam during application may indicate reduced concentrate pick-up; increasing proportioning rate from 3% to 6% can be a temporary solution.
System Flushing Procedure
- Throttle engine discharge pressure down to idle before flushing.
- Flush the hoseline with water until foam is no longer visible.
- Engage the eductor backflush button only under 75 psi; do not force above this pressure.
- Ensure pressure at the eductor remains below 75 psi while flushing the hoseline.
- Shut down the nozzle and expect rapid discharge at a 6% setting during flushing.
- Use the red flush button to run fresh water through the pick-up tube until no foam is visible.
- Clean any remaining foam residue from the wand metering head and eductor with warm water.
Elevated Foam Stream Evolutions
125 GPM Flow Rate
- Conduct a size-up to determine optimal apparatus placement, product type, and proximity to water supply.
- If a hydrant is within 300', the aerial can draw directly from it.
- Prepare equipment: replace master stream nozzle with a reducer and appropriate fog nozzle rated at 125 gpm @ 75 psi.
- Connect the in-line foam eductor to a pump discharge and establish the necessary hose connections.
- Charge water line to a minimum EDP of 200 psi and check for suction before immersing the pick-up tube into foam containers.
250 GPM Flow Rate
- Follow similar size-up procedures as for 125 GPM flow rate.
- Use fog nozzle rated at 250 gpm @ 50 psi.
- Set up two foam lines from different apparatus for greater effectiveness.
- Ensure aerial discharge and drain valves are closed before charging lines.
350 – 1000 GPM Flow Rate
- Requires an ARFF (Aviation Rescue and Firefighting) vehicle, with flow dependent on the resource type.
- Similar size-up for positioning and water supply considerations.
- Use a 5” hoseline connected to the rear aerial inlet.
- All pumping managed by the ARFF vehicle while aerial operations focus on the master stream.
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Description
Test your knowledge on the various types of firefighting foams, their specific applications, and operational procedures. This quiz covers Class A and Class B foams, including their definitions, uses, and considerations for their application in fire emergencies.
