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25 Cards in this Set
- Front
- Back
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What type of foam do LFB use? |
Low and high expansion foam Alcohol resistant aqueous film forming foam (ARAFFF) |
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What are the low expansion foam rates? |
Expansion ratio from 2:1 to 20:1 but usually between 5:1 to 15:1 |
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What are the high expansion foam ratios? |
Expansion ratio from 200:1 to 2000:1 but usually not more than 1200:1 |
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How does foam extinguish the fire? |
By: Diluting the surrounding air with water vapour Isolating fuel from oxygen in the air Forming a sealing blanket over the surface of the flammable liquid Intercepting radiant heat from flames Cooling the fuel by absorbing the heat |
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When foam is produced there are three factors that can be varied: |
Volume of air mixed with a volume of solution The size of the bubbles (hi ex only) Quantity of foam concentrate added |
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What does the effectiveness of the foam rely on? |
Concentration in good condition Correct mixture of concentrate used Good maintenance of equipment Correct pump pressure used for the equipment |
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What setting is needed to supply foam to a delta 400 branch? |
400 lpm at 6 bar 23 metre throw 15 lpm of foam |
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What are the required settings to supply foam to a ground monitor? |
950 lpm at 7 bar will deliver foam at a 12:1 ratio |
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How do you apply low ex foam? |
Gentle application from a distance Rain down by applying into the air above the fuel Rolling on to the ground in front of the fuel Off wall or indirect application allowing the foam to sink into the fuel |
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What type of buildings will have a foam inlet? |
Buildings containing oil fuel, oil fired boilers or other flammable liquids. The inlet is usually a tapered orifice suitable for most types of LX branches. |
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What equipment is used to deliver high expansion foam? |
Angus Turbex mk 2 carried on bulk foam units |
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What do bulk foam units carry |
8 x 1000 litre IBC of low ex 1 x 1000 litre IBC of hi ex 1 x Angus Turbex mk 2 2 x foam monitors 30 metres of foam discharge polythene tubing.
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What pressure does the Angus Turbex mk 2 operate at |
7 bar |
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Where is hi ex foam especially useful? |
Basements, ships holds and cable tunnels |
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What may affect the volume of foam penetrating a compartment? |
The back pressure caused by the products of combustion which will halt the spread of hi ex foam. Compartments should be ventilated to prevent this and these should be protected using covering jets |
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What safe systems of work should always be used when committing firefighters to Hi ex foam? |
Guidelines and effective communication equipment |
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Where are bulk foam units kept? |
Barking, harrow and kingston |
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How much foam can the RTPP draw into the pump casing? |
Up to 64lpm |
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How much foam does the onboard foam tank hold? |
80 litres |
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How long is the foam transfer tube? |
2 metres and up to four can be connected together |
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How to get foam to work from appliance foam tank. |
Engage PTO Open Tank to pump valve Engage pump Select low pressure mode Ensure both hose reel valves are closed Use the RTPP to preselect the foam rate to provide a 3% solution and select the flow rate appropriate for the equipment in use. Select desired water pressure setting on epump Set foam tank to RTPP valve open
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Knock off foam from onboard tank |
Pump speed to idle Disengage the pump Rotate the RTPP to zero Close Foam tank to RTPP valve Commence with flushing procedure Refill the foam tank |
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How are the bubbles made in a foam solution? |
Air is drawn into the nozzle through the Venturi effect. As the foam solution passes through the centre of the nozzle, a low level of pressure is created, which draws air into the nozzle |
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Supplying foam from an external foam supply |
1. Tank to pump valve open 2. Connect external foam supply using foam transfer tube 3. Engage pump 4. Select low pressure mode 5. Ensure both hose reels are closed 6. Use the RTPP rotary control to pre select the foam to provide a 3% solution to suit the flow rate of the foam equipment in use 7. Set the desired water low pressure setting on epump 8. Set the foam pick up to RTTP valve to open 9. Commence firefighting |
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How much foam does an Angus turbex use? |
4.5 Lpm |
