Presentation on theme: "1. Identify how foam works 3. Discuss the different types of foam available on the market 4. Talk about the foam we have here with an in-depth look at."— Presentation transcript:
1. Identify how foam works 3. Discuss the different types of foam available on the market 4. Talk about the foam we have here with an in-depth look at F How do we use foam 6. Use of the new foam system on E Go out and create some foam using 2522 and portable eductor 2. Discuss all of the different classifications of foam
Burnback Resistance - The ability of a foam blanket to resist direct flame impingement such as would be evident in a partially extinguished petroleum fire. Drainage Rate - The rate at which solution drains from a foam. Expansion - The ratio of volume of foam formed to the volume of solution used to generate the foam; for example, an 8 expansion means 800 gallons of foam from 100 gallons of solution. Foam Liquid or Concentrate - The foaming agent for mixing with the appropriate amounts of water and air to produce finished foam. Foam Solution - A homogeneous mixture of water and foam liquid. Foam Stability - The relative ability of a foam to Withstand spontaneous collapse or breakdown from external causes, such as heat or chemical reaction. Polar Solvent - A liquid whose molecules possess a permanent electric moment. Examples are amines, ethers, alcohols, esters, aldehydes, and ketones. In fire fighting, any flammable liquid which destroys regular foam is generally referred to as a polar solvent (or is water miscible). Polymeric Membrane - A thin, durable, cohesive skin formed on a polar solvent fuel surface, protecting the foam bubbles from destruction by the fuel; a precipitation which occurs when a polar solvent foam comes in contact with hydrophilic fuels such as isopropanol, ethanol and other polar solvents. Proportioner - The device where foam liquid and water are mixed to form foam solution.
Foam helps us put out fires by 4 different means….. motheringooling eperating enetrating
Classifications of Foam By Type of Material Class A Paper, wood, textiles, rubber, etc. Class B Flammable liquids, gasoline, diesel Class C, D, K C- electrical D- Flammable metals K- Restaurant grease, oils Man Made Or Natural Protein means natural. Foams can be a mixture of man made and natural Expansion Ratio Either Hi, Medium, Or Lo Lo = Up to 20:1 Med from 20:1 – 200:1 High from 200:1 – 1,000:1
Different Types of Foams On The Market Protein Foam May be used in 3% or 6% mixture Protein based Low expansion Good re-ignition (burn-back) resistance Excellent water retention High heat resistance and stability May be used with fresh or salt water Performance can be affected by freezing and thawing Concentrate can be freeze protected with anti-freeze Not as mobile or fluid on fuel surface as other low-expansion foams Primary use on Class B fires involving hydrocarbons Used to protect flammable and combustible liquids in storage, transport, and processing May be used in 3% or 6% mixture Protein and synthetic based; derived from protein foam Fuel shedding Long-term vapor suppression Good water retention Excellent, long-lasting heat resistance Performance not affected by freezing and thawing Maintains low viscosity at low temperatures Can be freeze protected with anti-freeze May be used with fresh or salt water Non-toxic and biodegradable after dilution Good mobility and fluidity on fuel surface Pre-mixable for short periods of time Primary used for hydrocarbon vapor suppression Used for subsurface application to hydrocarbon fuel storage tanks and extinguishing in-depth crude petroleum or other hydrocarbon fuel fires Fluoro-protein Foam
Different Types of Foams On The Market Aqueous Film Forming Foam (AFFF) May be used in 1%, 3% or 6% mixture Synthetic based Good penetrating capabilities Spreads vapor-sealing film over and floats on hydrocarbon fuels Can be used through non-aerating nozzles Performance may be adversely affected by freezing and storing Has good low-temperature viscosity Can be freeze protected with anti-freeze Can be used with fresh or salt water Can be premixed Primary use in controlling and extinguishing Class B fires Used in handling land and sea crash rescues involving spills, extinguishing most transportation-related fires, wetting penetrating Class A fuels, and securing un-ignited hydrocarbon spills May be used in 3% or 6% mixture AFFF concentrate to which polymer added Can be used on both polar solvents and hydrocarbon fuels (used on polar solvents at 6% solution and on hydrocarbon fuels at 3% solution) Forms a membrane on polar solvent fuels that prevents destruction of the foam blanket Forms same aqueous film on hydrocarbon fuels as AFFF Fast flame knockdown Good burn-back resistance on both fuels Not easily premixed Primary use on fires or spills of both hydrocarbon and polar solvent fuels Alcohol Resistant Aqueous Film Forming Foam (AR-AFFF)
Film Forming Flouroprotein Foam (FFFP) Different Types of Foams On The Market FFFP’s are a combination of fluorochemical surfactants with protein foam. They are designed to combine the fuel tolerance and burnback resistance of a fluoroprotein foam with an increased knockdown power. FFFP foams release an aqueous film on the surface of the hydrocarbon fuel. High Expansion Foam Used at expansion ratios of greater than 200:1 For use on large enclosed areas, basements, ships hulls, etc. Can be used on Class A materials
Proportioning Equipment Elkhart Brass Model 240 In-Line Eductor
Proportioning Equipment Akron Brass Model 768 Foam Tube For Ratios Of Up To 12:1
Other Equipment on the market By-Pass Inline Eductor Foam Nozzle Tubes High Exp. Foam Tube Foam Nozzle
Rates of application for foam How much foam will you need ???? To determine the amount of foam you need, use the following formulas. 1.Determine area of spill in square feet. 2.Multiply that number by either 0.1 for hydrocarbon spills and 0.2 for polar solvents. This will give you the required flow in GPM’s. 3.Take that number and multiply it by the percentage of foam you are using, either 1%, 3%, 6%, etc. This number will tell you how much concentrate you will need per minute. 4.Finally, take the answer from number 3 and multiply by 15 (the number of minutes NFPA requires as a minimum application time) and that will give you the total number of gallons of foam concentrate required.
Rates of application for foam How much foam will you need ???? NFPA recommended application rate for Film Forming Type Foams equals 0.1 gpm (foam solution) per square foot of fire with a MINIMUM RUN TIME OF 15 MINUTES. Examples of application rates for Hydrocarbons: AN AREA OF 2000 SQUARE FEET OF REGULAR GASOLINE IS BURNING. YOU HAVE UNIVERSAL PLUS 3% / 6% FOAM AVAILABLE FOR SECURING THE FLAME..10 gpm/sq.ft. X 2000 sq.ft. = 200 gpm of FOAM SOLUTION REQUIRED..03 X 200 gpm = 6 gallons of 3% CONCENTRATE REQUIRED per minute. 6 gal. X 15 minutes = 90 gallons of 3% AFFF CONCENTRATE REQUIRED to control, extinguish and initially secure a 2000 sq.ft. hydrocarbon fire. For Hydrocarbons
Rates of application for foam How much flammable liquid spill can we cover with our current foam supply ???? For hydrocarbons: Area = foam concentrate reserve X aeration factor of your nozzle divided by or Area = gallons of foam X 8/0.045 For polar liquids: Area = gallons of foam X 8/0.18 As an example, if you have 20 gallons of foam concentrate and you have a gasoline spill, how big of an area can you blanket with foam? 1. Area = 20 gallons X 8/ Area = 3, square feet or 59.6’ X 59.6’
Procedure for application of foam 1.Determine the type of liquid spilled, either a hydrocarbon or polar solvent 2.Choose the foam that would best fit the situation. 3.Estimate the amount of fuel spilled in square feet 4.Use the appropriate formula to estimate the amount of foam required. If additional foam is required, make the appropriate calls to get more foam. 5.Set-up the foam operation. Determine if eductor will be on the pump discharge or somewhere else in line. 6.Determine if an aspirating nozzle is required. For F-500, it is generally not required. 7.Apply foam using appropriate technique for 15 minutes. 8.Assess the situation after 15 minutes. Use a combustible gas meter to monitor for explosive atmospheres. Apply more foam if necessary.
Setting up the foam operation Connecting directly to pump discharge. 1.Connect eductor to discharge outlet of apparatus then connect hose to discharge of eductor. 2.The eductor must be used with a nozzle having the same rated flow (i.e. 95 gpm nozzle with a 95 gpm eductor) 3.Adjust the metering device to the correct setting for the required percentage of concentrate. 4.Check by-pass valve. If eductor is the by-pass type, be sure that the valve is in the FOAM position (closed). If the valve is in the WATER position, eductor will not pick up foam concentrate. 5.Open discharge and set proper flowing pressure. Eductor inlet pressure of 200 psi is required for accurate proportioning of concentrate into the water stream and efficient nozzle performance. Be sure that the nozzle is fully open. 6.Insert pick-up tube into foam supply. There will be a dely of 12 – 15 seconds before the foam solution will be discharged at the nozzle in a typical system. 7.The hose lay between the eductor and the nozzle must not exceed the recommended length for the combination of flow rate and hose size being used.
Setting up the foam operation
Alcohol Resistant Aqueous Film Forming Foam First, an aqueous film is formed in the case of a conventional hydrocarbon fuel, or a polymeric membrane in the case of a polar solvent fuel Second, regardless of the fuel type, a foam blanket is formed which excludes oxygen and from which drains the liquids that form the film or the polymeric membrane. Third, the water content of the foam produces a cooling effect. 3 Actions
Alcohol Resistant Aqueous Film Forming Foam Just like AFFF but a polymer is added Pseudoplastic and thixotropic, product will be gel-like until a shear force is applied and then the product will flow, similar to ketchup Can be used on class A fires Can be used with or without air aspirating nozzle. The minimum and maximum usable temperature for ANSULITE ARC 3% or 6% AR-AFFF Concentrate in this equipment is 35 °F (2 °C) to 120 °F (49 °C) respectively.
Does not fall into any previous foam category
What can we use F-500 on? Class A Fires ? Yes! Class B Fires ? Yes! 0.5 % – 1.0 % 1 % - 3 % 1 % for spills up to and including 50 gallons 3 % for spills over 50 gallons (Hydrocarbons) 6 % for polar solvents Class D Fires ? Yes!
How does F-500 work? Most foams create a blanket over the liquid surface, but F-500 does not work that way. F-500 “encapsulates” the liquid in what is called a “micelle encapsulator”. This renders the flammable liquid un- flammable for the duration of the incident, and makes transfer of the material safer. F-500 still cools the flammable liquid to the point it does not give off flammable vapors. It also reduces the surface tension of water for easier penetration of class A materials It is said to absorb heat as well Can be used without an expansion nozzle and with a smooth bore nozzle.
F-500 Proportions One 5 gallon container in a 500 gallon tank = 1% For use on hydrocarbon fires less than 50 gallons Pre-mix in tank and run off tank only until tank is empty, then re-mix for additional foam if needed. 500 Gallon Tank Three 5-Gallon containers in a 500 gallon tank = 3% For use on hydrocarbon and polar solvent fires greater than 50 gallons Pre-mix in tank and run off tank until tank is empty, then re-mix for additional foam if needed. 500 Gallon Tank
F-500 APPLICATION RATES
TROUBLESHOOTING 1) Make sure nozzle is always FULLY opened during operation. 2) Assure that nozzle and eductor GPM settings are equal. 3) Check for kinks in hose lines. 4) Check for adequate pump pressure. 5) Check for air-tight seal around pick-up tube/hose connections. 6) Check for kinks or blockage in pick-up tube and hose lines 7) Check metering valve to make sure it is open 8) Check for clogged nozzle. 9) Is nozzle elevated too high above eductor 10) Check the check ball (listen for rattle, look for flow into concentrate bucket).
GASAHOLS-MTBE-OTHER OXYGENATED FUEL SOURCES METHANOL ETHANOL MTBE-METHYL TERTIARY BUTYL ETHER -> made from isobutylene, a refinery waste product which is normally recycled or burned, and methanol which is produced from natural gas. It now has the largest share of the oxygenate market. TERTIARY AMYL METHYL ETHER (TAME), ETHYL TERTIARY BUTYL ETHER (ETBE) DI-ISOPROPYL ETHER (DIPE). As long as the mixture is not greater than 10 %, use standard hydrocarbon percentages of foam concentrate