Foam Operations for Firefighters

TOPIC: FOAM OPERATIONS FOR FIREFIGHTERS TIME REQUIRED: THREE HOURS MATERIALS: FOAM NOZZLES, FOAM EDUCTORS, FOAM SOLUTION, HOSE AND APPARATUS (OPTIONAL) REFERENCES: ESSENTIALS OF FIRE FIGHTING, FOURTH EDITION, IFSTA PUMPING APPARATUS...


      j. Not as mobile or fluid on fuel surface as other low-expansion foams

     k. Primary use on Class B fires involving hydrocarbons

         l. Used to protect flammable and combustible liquids in storage, transport, and processing

        2. Fluoroprotein

             a. May be used in 3% or 6% mixture

             b. Protein and synthetic based; derived from protein foam

             c. Fuel shedding

             d. Long-term vapor suppression

             e. Good water retention

             f. Excellent, long-lasting heat resistance

             g. Performance not affected by freezing and thawing

            h. Maintains low viscosity at low temperatures

            i. Can be freeze protected with anti-freeze

            j. May be used with fresh or salt water

           k. Non-toxic and biodegradable after dilution

                  l. Good mobility and fluidity on fuel surface

           m. Pre-mixable for short periods of time

           n. Primary used for hydrocarbon vapor suppression

           o. Used for subsurface application to hydrocarbon fuel storage tanks and extinguishing in-depth

               crude petroleum or other hydrocarbon fuel fires

  3. Aqueous Film Forming (AFFF)

      a. May be used in 1%, 3% or 6% mixture

      b. Synthetic based

      c. Good penetrating capabilities

     d. Spreads vapor-sealing film over and floats on hydrocarbon fuels

     e. Can be used through non-aerating nozzles

     f. Performance may be adversely affected by freezing and storing

    g. Has good low-temperature viscosity

    h. Can be freeze protected with anti-freeze

    i. Can be used with fresh or salt water

    j. Can be premixed

   k. Primary use in controlling and extinguishing Class B fires

   l. 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

  4. Aqueous Film Forming – Alcohol Resistant (AFFF-ATC or AFFF-ARC)

      a. May be used in 3% or 6% mixture

      b. AFFF concentrate to which polymer added

      c. Can be used on both polar solvents and hydrocarbon fuels (used on polar solvents at 6%

          solution and on hydrocarbon fuels at 3% solution)

      d. Forms a membrane on polar solvent fuels that prevents destruction of the foam blanket

      e. Forms same aqueous film on hydrocarbon fuels as AFFF

      f. Fast flame knockdown

      g. Good burn-back resistance on both fuels

      h. Not easily premixed

      i. Primary use on fires or spills of both hydrocarbon and polar solvent fuels

  5. High Expansion

      a. Synthetic detergent based

      b. Proportioned at 1-1/2% with water

      c. Special purpose, low water content

      d. High air-to-solution ratios: 200:1 to 1,000:1

      e. Performance not affected by freezing or thawing

      f. Poor heat resistance

      g. Prolonged contact with galvanized or raw steel may attack these surfaces

      h. Primary use in extinguishing Class A and some Class B fires, flooding confined spaces,

          volumetrically displacing vapor, heat, and smoke, reducing vaporization from liquefied natural

          gas spills, extinguishing pesticide fires, suppressing fuming acid vapors, suppressing vapors in

          coal mines and other subterranean space, suppressing vapors in concealed spaces in basements,

          as an extinguishing agent in fixed extinguishing systems for industrial use

      i. Not recommended for outdoor use

  6. Class A

      a. Synthetic

      b. Wetting agent that reduces surface tension of water and allows it to soak into combustible

          materials

      c. Rapid extinguishment with less water use than other foams