FT 105 Ch. 3

  1. Combustion
    Planned and controlled self sustaining chemical reaction between a fuel and oxygen with the evolution of heat and light.
  2. Fire
    Rapid self sustaining oxidation process that involves heat, light, and smoke in different quantities.
  3. Fire triangle
    Older three sided model used to describe the necessary requirments for fire.
  4. Fire Tetrahedron
    Four sided model describing heat, fuel, oxygen, and chemical reaction need for combustion.
  5. Free Radicals
    Molecular fragment possessing at least one upaired electron.
  6. Pyrolysis
    Break down of a solid into gaseous components when heated.

    A.K.A Thermal decompostion
  7. Spontaneous Combustin
    Material self heats to its piloted ignition temp. then ignites.
  8. Piloted Ignition Temperature
    Ignition temp. of a liquid fuel, when heated it will self ignite.
  9. Particulates
    Unburned products of combustion seen in smoke.
  10. Entrainment
    Captured cooler air that replaces the rising heated air surrounding the point of combustion.
  11. Smoldering Combustion
    Absence of flame with presence of hot materials in the surface where oxygen diffuses into the surface of the fuel.
  12. Acrolein

    Strong respiratory irritant produced when polyethylene is heated, or when materials with cellulose smolder.
  13. Hydrogen Chloride

    • Colorless but pungent 
    • irritating gas givin off during thermal decomposition of materials that contain chlorine.
  14. Hydrogen Cyanide

    Colorless, almond odor

    20X more toxic than CO

    Asphyxiant can be absorbed through skin

    Produced from combutsion of natural materials (wool, silk), or materials containing urea.
  15. Carbon Dioxide

    Colorless, odorless

    Nonflammable gas

    Can cause asphyxia by eliminating oxygen from confined space.
  16. Nitrogen Oxides
    NO2 and NO

    Smoke is a reddish brown color

    Can have delayed symptoms
  17. Phosgene

    Highly toxic, colorless gas

    Disagreeable odor of musty hay

    Symptoms delayed several hours from exposure

    Produced when freon or refrigerants come into flame contact.
  18. Stoichiometry of Reaction
    Proportion of fuel to oxygen and the resulting end products.
  19. Stoichiometry 
    Ideal burning situation where there is perfect balance of fuel and oxygen.
  20. Flamming Coumbustion
    Exothermic chemical reaction with flames occuring between a substance and oxygen.
  21. Diffuse Flamming
    Combustion process where the flames are part of the actual process.
  22. Class A Fire
    Ordinary combustibles.

    Extinguished by water.
  23. Class B Fires
    Flammable liquids.

    Extinguished by removing oxygen supply and cooling.
  24. Class C Fire
    Electrical fire

    Extinguished by cutting of power.
  25. Class D Fire
    Combustible metals

    Extinguish by specific foam mixture for different metals.
  26. Class K Fire
    Cooking Oil

    Extinguish by dry or wet chemical depending on sopanification. 
  27. Saponification
    Process of chemically converting fatty acid to sopa or foam.
  28. Fire Stages


    Fully developed

  29. Incipient Stage
    Point in which the 4 components of the fire tetrehedron come together and materials reach there ignition temp.
  30. Growth Stage
    Fire increases fuel consumption and heat generation.
  31. Fully Developed Stage
    Maximum Fuel consumption and heat occurs.
  32. Flame Over
    Flames travel up and long uburned gases during fire development.
  33. Flashover
    Sudden event that occurs when all contents of a confined space reach there ignition temperature and ignite simultaneously.
  34. Backdraft
    Violent reignition of closed container that has consumed all the oxygen within the container when new oxygen is introduced.
  35. Decay Stage
    Fire has consumed all available fuel and temperaure begins to decrease.
  36. Compartmentation
    Used in high rise buildings to provide a safe environment within the structure where persons can be protected from fire.
  37. Stack Effect
    Temp. difference between inside of a bulding and the outside of the building
  38. Relative Humidity
    Ratio of moisture in a given volume to the amount that volume would contain if saturated.
  39. Law of Latent Heat of Vaporization
    Heat that is absorbed when one gram of liquid is transformed into vapor at the boiling point under one atmospheric pressure.
Card Set
FT 105 Ch. 3
Combustion Process