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Foam Application Rates for E85 and E-95 Application Rates Described in Terms of the Amount in Gallons of Foam Solution Reaching the Total Square Footage of the Fuel Surface Every Minute • Critical Application Rate - lowest rate at which a foam will extinguish a fire under a particular set of ideal conditions (.06 for gasoline) • Minimum application rate - the amount found by tests to be the most practical in terms of speed and control of agent required Application Rates Foam concentrate application rates may be as low as 0.06 gpm for gasoline to as much as 0.20 for polar solvents (ethanol). Minimum foam concentrate application rates. Application rates are listed as gpm • .10 for flammable liquid spill/fire • .16 for tank diameter of less than 150’ • .18 for tank diameter of less than 200’ • .20 for tank diameter of less than 250’ • .20 Polar solvent spill/fire Polar Solvent = Ethanol NFPA 11 “Tests have shown that foam may travel effectively across at least 100 feet of burning liquid surface”. “Sometimes” Application Rates Calculated 1. Determine Area of Hazard 2. Choose Appropriate Application Rate 3. Rate x Area = GPM of Foam Solution 4. Solution GPM x % Used = Concentrate GPM 5. Concentrate GPM x Time = Total Concentrate • Storage Tanks - 60 Minute Flow Time • Spills - 15 Minutes Flow Time Application Rates Calculated Example • Determine Area of Hazard = 3000 sq. ft • Application Rate = 0.20 GPM • Rate x Area + 600 GPM of Solution • 600 GPM x 3% Used = 18 GPM Concentrate • 18 x 15 minutes application time = 270 gals needed This calculation example is based on a spill area of 75’ x 40’. Requirements • Based upon the 75’ x 40’ spill footprint one can see that 270 gallons of 3% foam concentrate would be needed. • If we assume every gallon of 3% foam concentrate requires 97 gallons of water, we can see that we would also need 26,190 gallons of water (97 x 270) to maintain the required 15-minute application period. Preplan Based upon the previous example: • Where would you get 270-gallons of 3% AR-AFFF concentrate? • Where would you get 26,190-gallons of water in an area without hydrant’s? Quick Foam Flow Work Sheet 1. Determine Area of Hazard* = SQ. FT. * (L x W) or (.785 D2) 2. Choose Application Rate = 3. 4. 5. Sq. Ft. X GPM X Flow rate of solution Gallons GPM GPM = % % of FLC GPM = Gallons Gallons of FLC per/minute Minutes Gallons X = Gallons of FLC per/minutes Duration of flow Total FLC Required • NFPA 11 states that a minimum15-minute flow duration is required. • If you calculate this minimum requirement in all of your foam concentrate requirements this should get you off to a good start. • Do not hesitate to calculate more if there is a large spill or fire. • Gasohol (not E-95 or E-85) fires may be extinguished using conventional AFFF and ARAFFF but increased application rates may be necessary especially for prolonged burn back resistance.