![Instructors ,[object Object],[object Object]](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Recommended
More Related Content
What's hot
What's hot (20)
Similar to Foam Use Class PP
Similar to Foam Use Class PP (20)
Recently uploaded
Recently uploaded (20)
Foam Use Class PP
- 1. 7TH ANNUAL ARKANSAS FIRE BOAT SCHOOL FRIDAY AND SATURDAY, JUNE 4TH AND 5TH, 2010 SPILLWAY LAUNCHING RAMP/IRON MOUNTAIN RESORT DEGRAY LAKE, ARKANSAS
- 6. C A B D Flammable Liquids Gasoline Acetone Kerosene Ordinary Combustibles Wood Cloth Paper Wool Energized Electrical Equipment Transformers Computers Electric Ovens Combustible Metals Magnesium Titanium Zirconium Sodium Potassium
- 11. A measure of the durability and viscosity of foam Foam Solution Wet Foam Fluid Foam Dry Foam 0.1%-1% 0.2% 0.5% 1.0%
- 12. Class A foam attack - 125 gpm at 0.5%
- 13. NOTE: Lack of smoke; ability of Class A foam to bond with carbon
- 20. Foam Bubble Class A Class B Emulsifiers Carbon-loving Good Spreading Excellent wetting Carbon-shedding Excellent spreading Poor wetting Designed to react with the fuel source
- 21. When plain water is applied to fuel, surface tension causes water to bead up …
- 22. Add Class A foam to plain water… solution spreads and penetrates the fuel…
- 23. … moisture content of the fuel increases and chance of rekindle is reduced.
- 25. 5.3.4.1.1 Wetting agent solutions at the concentractions specified by the manufacturer shall be evaluated to, and comply with, the requirements of UL711 for Class A fires utilizing a 3A wood crib. 5.3.4.1.2 The test shall be conducted utilizing a 9.5 L (2.5 gal) listed 2A rated water extinguisher. U.L. 711 is the portable extinguisher test series. A 2.5 gallon extinguisher can never get more than a 2A rating with plain water. When a wetting agent or Class A foam is added to the water then the extinguisher is more effective. The 3A test fire is larger than the 2A and is two (2) two times the amount of fire loading, in general, as the 2A fire loading. When an agent in an extinguisher passes the test cycle, then the agent is rated by U.L. as better than plain water.
- 35. Well….for one thing, at the concentrate level, Class A foam and Class B AR AFFF don’t like each other……
- 43. EDUCTOR A mixing system that uses water pressure to draw foam concentrate into the water stream for mixing.
- 58. Around the Pump Proportioner
- 60. Do NOT Recirc water when foam system is on
- 61. Set and monitor water flow rate and adjust metering valve accordingly
- 62. Water Tank Foam Tank Flow Meter Water Pump
- 68. Non-Aspirated
- 69. Automatic Nozzles with Foam Tube
- 70. Low Expansion
- 71. Medium Expansion
- 73. High Expansion
- 74. Ground Monitor
- 78. A Class B foam must form a cohesive barrier over the surface of the liquid that is impermeable to product vapors A layer of foam over the liquid surface is usually a cohesive barrier. A film is often not a vapor barrier
- 81. AREA x RATE = GPM of Solution 2000 .10 200 gpm GPM x %CON. = GPM of Concentrate 200 .03 6 gpm GPM x %Water = GPM of Water 200 .97 194 gpm GPM x TIME = TOTAL GAL CONC. 6 15 90 gal GPM x TIME = TOTAL GAL WATER 194 15 2910 gal Ignited Fuel Spill: Gasoline Application Example 3% Concentrate 50’ 40’
- 84. AREA x RATE = GPM of Solution 2000 .10 200 gpm GPM x %CON. = GPM of Concentrate 200 .01 2 gpm GPM x %Water = GPM of Water 200 .99 198 gpm GPM x TIME = TOTAL GAL CONC. 2 15 30 gal GPM x TIME = TOTAL GAL WATER 198 15 2970 gal Ignited Fuel Spill: Gasoline Application Example 1% A 1% Hydrocarbon Foam Is Much More Efficient In Terms Of Storage And Handling 50’ 40’
- 87. AREA x RATE = GPM of Solution 2000 .20 400 gpm GPM x %CON. = GPM of Concentrate 400 .06 24 gpm GPM x %Water = GPM of Water 400 .94 376 gpm GPM x TIME = TOTAL GAL CONC. 24 15 360 gal GPM x TIME = TOTAL GAL WATER 376 15 5640 gal Ignited Fuel Spill: Ethanol Application Example 6% 50’ 40’ A 6% Alcohol foam will make this fire a logistics issue. Where is 360 gallons of foam going to come from?
- 89. AREA x RATE = GPM of Solution 2000 .20 400 gpm GPM x %CON. = GPM of Concentrate 400 .03 12 gpm GPM x %Water = GPM of Water 400 .97 388 gpm GPM x TIME = TOTAL GAL CONC. 12 15 180 gal GPM x TIME = TOTAL GAL WATER 376 15 5640 gal Ignited Fuel Spill: Methanol Application Example 3% A 3% Alcohol Foam Is Efficient In Terms Of Storage and Handling As Compared To 6% Alcohol Foam. Large Amounts Of Concentrate Are Still Required 50’ 40’
- 92. You can make a difference Get back to the basics! National Fallen Firefighters Foundation Life Safety Initiatives 2004
- 93. Duty and responsibility -- Make EVERY DAY a TRAINING DAY….so that… EVERYONE GOES HOME! Firefighter Life Safety Initiatives
Editor's Notes
- Direct and Indirect Attack Mop-up/Overhaul Exposures Structural and wild land fires
- Most situations now days are class A situations. Unless there is an significant amount of fuel, in depth (over 1”) Putting Class A foam on tires, in a wet state can allow the water to cool because of its ability to stick to the tires. Exposure Protection: Class A foam is excellent for exposure protect. The foam will keep the water on a structure where the water would run off.
- The focus of this presentation is Class A Ordinary Combustibles and some on Class B flammable and combustible liquids. We will compare the differences in the two foams. 2
- “We’re going to use foam now instead of water.” Foam is water. Most application rates are.3 to .5% leaving 99.5% water Better Cooling: Class A foam will increase the surface area of water. The result is that the water can turn to stream quicker resulting in quicker cooling. Less Rekindles: Class A foam is excellent for mop up applications because it improves penetration into the crevices of the fuel. The results are a reduction in rekindles. Reduced water damage: Because the foam knocks the fire down with less water and is more effective at mop up the water damage is substantial reduced to the structure. 2-3 times faster knockdown than water: The surface area of water is increased when it becomes foam. All of the water is on the outside of the water bubble, which increases the surface area. The water will turn to stream easier with the increase in surface area. One advantage, the increased steam conversion has to watched for one “disadvantage”... More steam. When you use foam, you will make more steam. Be prepared, and allow for the steam to escape.
- Class A foam is very good at making bubbles at very low percentages. Class A foam is carbon attractive. It makes the water stick to charred carbon based fuels Class A foam is a wetting agent, that reduces the surface tension that exists in water. This surface tension allows water to sit on surfaces and not soak in. Foam helps to increase the surface area of a gallon of water, is how you absorb more BTUs. A bubble will turn to steam much quicker than a droplet of water. This steam production is what makes foam capable of knocking fires down very quickly. During over-haul and mop-up type operations, the foam is effectively used as a wetting agent that has low surface tension that can soak in fast, and stay attached to the surfaces, because of the carbon affinity, or attractiveness of the soapy water. Exposure Protection: Class A foam is excellent for exposure protect. The foam will keep the water on a structure were the water would run off. The fact that Class A is used at such low percentages, is what makes it affordable to use on a regular basis.
- Strong degreaser- over time it can dry the oil out of leather boots/gloves or leather on turn out gear, if not washed off after each use. CONS – Raw concentrates will work on packing and seals. Understanding the use of Class A foam on a Class B fire, It will mix with over time Could have re-ignition A foam does not have that high burn back resistance
- Accuracy in foam proportioning is important. If your proportioner is off by 30%, just remember that 1/10 of 1% is equal to a gallon of concentrate per 1,000 gallons of water. Four types of foam. Foam Solution - Wet water, no real foam bubbles. Wet Foam - Frothy wet foam, a little foam bubble structure, a very quick drain time. USE- overhaul or mop-up. Fluid Foam - a higher bubble producer, slower drain time. USE - initial attack on most fires. Dry Foam - very high bubble producer, very slow drain time. USE- to cover and protect, exposure protection.
- REMOVING FUELS – If we take a quantity of water and cause it to spread over and also penetrate the surface of the fuel plus stay there for some extended period of time, have we not made the fuel wet and thus removed it from availability for combustion? The answer is again, yes. INTERRUPTION OF THE CHEMICAL CHAIN REACTION – This is the hardest one to understand but, the easiest to see (the visual effect of foam) NO SMOKE. The hydrocarbon molecule is a chain molecule and it fractures many times in the combustion process into fragments or free radicals. These fragments are actively seeking others to recombine with just to fracture again (the chain reaction). The foam molecule actively seeks out the available fragments containing the carbon atom and bonds with them in a permanent bond thus removing it from the chain reaction.
- Class A: High infinity for carbon, readily bonds with carbon to wet the fuel causing extinguishment and/or preventing or limiting ignition. Class B: Does not like carbon. Does not react with the fuel, permitting the foam blanket to stay on top of the fuel surface for extended period. Emulsifiers: React with fuel to limit vapor release. Used at high rates, 3% to 6% or higher.
- Most fuel storage facilities, airports, and refineries forbid the use of Class A or dual purpose foams. Note also that dual purpose foams have not been certified to be used on alcohol fuel. The only foams that have worked well on alcohol is the AR-AFFF or ATC foams. It is very important to do your homework in purchasing Most often the good ones do not cost much more or any more than weaker foams.
- U.S. Forest Service is the only independent testing lab for Class”A” Foam
- Since first due engines respond to buildings and MVAs more than anything else, L.A. County has standardized on Class A foam on all engines.
- This is simply some Class A and ATC Class B concentrate that go together. The A sets the B off
- Even mixing Class B Foam from different manufactures can Gel. Should always use the same foam and never mix A with B foam of any kind, this causes a polymerization reaction. Approved class A concentrates should not gel, but might want to test the two before mixing in the same tank.
- Low expansion combination nozzle (impact foam) This is the type we will use for structural firefighter because of the reach Low expansion with the combination nozzle/smooth bore will have the same reach as water Low expansion foam tube, will loose 10%-15% of the stream reach
- We are not going to give you a full working knowledge of all the systems on the market, but will show a few and give you a vague idea of how they work.
- This is the inexpensive way to make foam on a trial basis. Also can be used in an emergency situation. However, this is not good practice for everyday operations because of the problems that are associated with batch mixing
- You would know starting out how much water was in the tank. But as the water starts to bubble, you will be guessing at how much foam to dump in the tank.
- When you open the tank to pump valve, it will cause foaming in the tank
- Manual tend to all be eductor type with constant flow class B systems
- These are the Cadillac units, These systems are designed to run class “A” foam. But some can run class “B” foam if spec’d the right way.
- This is a Scotty system on the grass truck at the Ohio Fire Academy, (around the pump) (wildland use)
- This is suitable for big Class B Foam Engines Small wildland class A engine Not for class A structural use
- Note, the water is being drawn off the discharge side and back around through an eductor (venturi) then back into the water stream on the suction (vacuum) side of the pump. When the system is charged, foam is available at all discharges. Remember the foam is being run true the pump, this requires the pump to be flushed after each use.
- A water flow in a conduit passes through a device that has a wheel in in the waterway. The wheel spins in proportion to the water velocity. The wheel sends an electric signal to a processor. The processor then controls the speed of an electric concentrate pump that pumps concentrate into the water stream. The stream is then divided into individual conduits by a manifold.
- Exposure protection Structural thermal insulation
- Impact is made on impact with a combination nozzle (straight stream) or solid bore. (floor/wall/ceiling) Aspirated nozzle will have a way to add air at the nozzle. CAFS is foam with the concentrate/air/water all being added at the truck.
- Air aspirated nozzle are required by N.F.P.A. for fuel fires
- The advantage? Aspirated foam makes a thicker blanket that will smother the fuel vapors faster/longer
- The disadvantage? Lack of reach makes it difficult to actually get the foam on the fuel
- This is a perfect medium expansion stream (round column of bubbles) Good for 3 dimensional fires (car/pallets/tires/debris in a structure)
- Large fuel spills/warehouses/airport hangers
- The average first due engine doesn’t respond to Class B incidents very often. MVAs with fuel spills aren’t really that much of a Class B hazard. Rubber tires and plastic interiors aren’t Class B either. In fact, Class foam is proven to be a better agent for rubber and plastic fires then Class B foam.
- Look at the pavement and area around the truck. The fire area was larger, but the spill has either burned off or has been suppressed. The ground fire is gone. The actual square footage of fire is fairly low.
- Know what you’re doing. Size it up and make sure Plan A is going to work.
- Look at the grass in front of the fire. The ground fire is gone. The actual square footage of fire is fairly low.
- Know what you’re doing. Size it up and make sure Plan A is going to work.