OXYGEN. 21% in air. Does not burn - Supports combustion. Increased oxygen will intensify burning

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3 FIRE Rapid self-sustaining oxidation of a fuel and oxygen in the presence of heat usually with the production of heat, light, and combustion byproducts

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5 OXYGEN 21% in air Does not burn - Supports combustion Increased oxygen will intensify burning

6 FUEL Physical States GAS LIQUID SOLID

7 Combustion requires that fuel be converted to vapor by heating

8 Size and shape of fuel influences ease of ignition and burning rate Smaller particles ignite more rapidly

9 CHEMICAL HEAT ELECTRICAL HEAT MECHANICAL HEAT NUCLEAR HEAT SOLAR HEAT

10 SELF-SUSTAINED CHEMICAL REACTION Allows for the continuous heating of the fuel and the production of vapors which join with oxygen to continue combustion Separates fire from slower oxidation reactions

11 EXINGUISHING PRINCIPLES Heat Control Oxygen Exclusion Fuel Removal Chemical Inhibition

12 CLASSES OF FIRE A CLASS Ordinary combustibles Cooling is normal extinguishment method

13 CLASSES OF FIRE CLASS B Flammable liquids and gases Extinguished by oxygen exclusion, cooling, fuel removal, or chemical inhibition

14 CLASSES OF FIRE CLASS C Energized electrical equipment Shut off power and extinguish by types of material burning

15 CLASSES OF FIRE CLASS D Combustible metals Extinguished with special extinguishing agents

16 CLASSES OF FIRE CLASS K Fires involving cooking oils used in commercial cooking operations

17 HEAT TRANSFER CONDUCTION Transfer of heat by direct contact from one body to another

18 HEAT TRANSFER CONVECTION Transfer of heat by movement of heated liquids or gases

19 HEAT TRANSFER RADIATION Transfer of heat as energy as heat waves

20 PHASES OF FIRE IGNITION When the four elements of the fire tetrahedron come together GROWTH After ignition, a fire plume develops & draws air from the surrounding space

21 THERMAL BALANCE ESTABLISHED Hottest gases accumulate at upper levels If water is improperly applied, it will cool the steam and cause steam and smoke to circulate within all levels

22 PHASES OF FIRE FLASHOVER Stage when area is heated to the point where flames flash over the entire area Temperatures generated during flashover can exceed 1500 F Occupants exposed to flashover usually will not survive

23 Flashover develops rapidly with little warning No one can accurately predict when flashover will occur

24 FLASHOVER SIGNS Heat build-up Rollover Thick dark smoke Free Burning

25 FULLY DEVELOPED Occurs when all combustible materials are involved in fire DECAY The rate of heat release declines as the fuels are consumed The remaining glowing embers result in moderately high temperatures

26 BACKDRAFT As a fire burns, large amounts of hot, unburned gases can collect in unvented areas without enough oxygen to ignite The introduction of air into this area will cause the gases to ignite with explosive force

27 Backdraft potential can be reduced by opening the building at the highest possible point to allow the gases to escape before entering an area

28 Smoke under pressure Dense gray-yellow smoke Little or no visible flame Smoke leaves in puffs Smoke-stained windows Muffled sounds Sudden inrush of air

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30 FIRE GASES Carbon Monoxide - most common fire gas Carbon dioxide Hydrogen cyanide Hydrogen chloride Phosgene Sulfur dioxide Hydrogen sulfide Hydrogen dioxide Nitric oxide Cyanic acid Ammonia Formaldehyde

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