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11 Cards in this Set
- Front
- Back
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What are the percentages of foam used and for what type of fires? |
3% for hydrocarbon fires and 6% for polar solvent (alcohol) fires |
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What are the 3 types of foam? |
Low, medium and high expansion (LFB only uses low and high) |
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What are the 4 different ways of applying foam? |
1. Gentle application 2. Raindown application 3. Rolling on application 4. Off wall- indirect application |
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Describe gentle application |
Gentle application involves applying foam to the surface fuel, with the foam making brach as far away as possible using the full trajectory of the foam stream |
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What are the care and safety considerations for using foam |
1. Never apply water onto the buring liquid 2. Always open the branch away from the fire until there is a consistent supply of foam 3. Make sure there is enough foam available to apply and maintain a complete sealing blanket of foam 4. Apply foam to the furthest point away from the fire 5. Any surrounding risks cooled with covering jets 6. Preserve foam blanket until the flammable liquid has had time to cool 7. Do not walk or drag hose through foam as this can disturb the sealing blanket |
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When would we use high expansion foam |
High expansion foam is useful for fires in basements, ships holds and cable tunnels |
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Where are the bulk foam units |
Barking Harrow and Kingston |
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How does foam extinguish fire |
Diluting, isolating (the fuel from oxygen in the air, cooling (the fuel) , forming (a sealing blanket) intercepting (radiant heat from flames) |
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What are the 3 factors that can be varied with producing foam |
Volume of air mixed with volume of solution Quantity of foam concentrate added The size of the bubbles |
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The effectiveness of foam depends on what 4 factors |
1. Concentrate in good condition 2. Correct mixture of concentrate used 3. Good maintenance of equipment 4. Correct pump pressure used for equipment |
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What does the branch operator need to do in order use foam? |
Use the aspirator over the branch, request pre-mixed foam with 6 bar pressure at the branch and flow ring set to 400lpm. |
