& Answers 100% Correct!
What are the conditions needed for a fire to occur? - ANSWERSfuel (material that acts
as a fuel)
sources of ignition (chemical, biological, or physical)
oxygen
What are the components of the fire tetrahedron? - ANSWERSheat, fuel, oxygen, chain
reaction
How do you stop a fire? - ANSWERSRemove any of the components of the fire
tetrahedron (i.e. remove fuel, oxygen, heat, or interrupt the chemical reaction)
Oxygen - ANSWERS-21% ambient air
-robust flaming combustion down to 15-16%
-surface combustion (smoldering) down to about 11%
-loss of consciousness in atmospheres with 12% or less oxygen
Heat - ANSWERSanything that produces the required temperature for ignition
-sun
-open flame
-chemical reaction
-sparks
-friction
Fuel - ANSWERS-only vapors burn
-liquids and solids must first be vaporized
-tendency of a substance to vaporize is an indication of its ability to burn
-liquids vaporize more readily than solids
Chain reaction - ANSWERS-you can have oxygen, heat, and fuel in the same place and
still not have a fire
-fuel and oxygen relationship must be balanced (i.e. in the flammable range)
-heat must be sufficient to bring fuel to its ignition
What is a flash point (of a liquid)? - ANSWERS-the lower temp that a liquid can give off
sufficient gas to form a flammable gas mixture near the surface of a liquid
-lowest temp at which we can have fire
-fire flashes across surface given sufficient oxygen and an external source of ignition
What is a Fire point? - ANSWERS-just above the flash point, liquid gives off flammable
vapors rapidly enough to support continuous combustion
, What is ignition temperature? - ANSWERS-substance starts to burn
-heat from external heat source
-auto-ignitio, no external source of ignition needed
What is auto ignition? - ANSWERSvapor generated ignites without any outside ignition
source
What is vaporization? - ANSWERSrate increases with temperature
What is spontaneous combustion? - ANSWERSheat is generated by a chemical action
within a substance and this continues until you have ignition (usually begins with
oxidation and combines oxygen and gives off energy in the form of heat)
What is lower flammable limit? - ANSWERSthe least concentration of flammable vapors
in air that will burn
What is upper flammable limit - ANSWERSthe greatest concentration of flammable
vapors in the air that will burn
What are the results of combustion? - ANSWERSsmoke, flame, heat, and gases
_____________ is the result of incomplete combustion - ANSWERSsmoke
White or light grey indicates ____________ burning - ANSWERSfree
Black or dark grey indicates a ______ fire or a _________ of oxygen - ANSWERShot,
lack
How is flame produced? - ANSWERSresult of conversation of the fuel to a state of
blazing combustion
How is heat generated? - ANSWERSrapid oxidation of the material
How are gases produced? - ANSWERSresult of combustion, may or may not be toxic
What are the characteristics of the incipient stage of a fire? - ANSWERS-cool
-good combustion
-little smoke
-good visability
-easy to breath
-radiative feedback
What are the characteristics of the freeborn stage? - ANSWERS-hot
-poor combustion
-dense smoke