Chapter 5 - Fire Behaviour Flashcards
The smallest particle of an element, which can exist alone or in a combination
Atom
A deflagration (explosion) from the sudden introduction of air into a confined space containing oxygen-deficient products of incomplete combustion (NFPA 1403)
Backdraft
A hot, high-volume, high velocity, turbulent, ultra-dense, black smoke that indicates an impending flashover or auto-ignitition.
Black Fire
An explosion that occurs when pressurized liquified materials (eg - propane/butane) inside a closed vessel are exposed to a source of high heat.
Boiling Liquid/Expanding Vapor Explosion
The temperature at which the vapor pressure of a liquid equals the surrounding atmospheric pressure (NFPA 1)
Boiling Point
A colorless, odorless, electrically non-conductive inert gas that is a suitable medium for extinguishing Class B and Class C fires (NFPA 10)
CO2/Carbon Dioxide
A toxic gas produced through incomplete combustion.
CO/ Carbon Monoxide
Energy that is created or released by the combination or decomposition of chemical compounds.
Chemical Energy
A fire in ordinary combustible materials, such as wood, cloth, paper, rubber and many plastics (NFPA 10)
Class A fire
A fire in flammable liquids, combustible liquids, petroleum greases, tars, oils, oil based paints, solvents, lacquers, alcohols and flammable gases. (NFPA 10)
Class B fire
A fire that involves energized electrical equipment (NFPA 10)
Class C fire
A fire in combustible metals such as Mg+, titanium, zirconium, sodium, lithium and K+
Class D fire
A fire in a cooking appliance that involves combustible cooking media (vegetable or animal oils and fats) (NFPA 10)
Class K fire
A chemical process of oxidation that occurs at a rate fast enough to produce heat and usually in the form of either a flow or a flame (NFPA 1)
Combustion
A space completely enclosed by walls and a ceiling. Each wall in the compartment is permitted to have openings to an adjoining space if the openings have a minumum lintel depth of 200mm (8in) from the ceiling and the total width of the openings in each wall does not exceed 2.4m (8ft). A single opening of 900mm (36in) or less in width without a lintel is permitted when there are no other openings to adjoining spaces (NFPA 13)
Compartment
Heat transfer to another body or within a body by direct contact (NFPA 921)
Conduction
Heat transfer by circulation within a medium such as a gas or a liquid (NFPA 921)
Convection
The stage of fire development within a structure characterized by either a decrease in the fuel load or available oxygen to support combustion, resutling in the lower temperatures and lower pressure in the fire area (NFPA 1410).
Decay Stage
Heat that is produced by electricity
Electrical Energy
Reactions that absorb heat or require heat to be added
Endothermic
Reactions that result in the release of energy in the form of heat
Exothermic
A rapid, persistent chemical reaction that releases both heat and light.
Fire
The lowest temperature at which a liquid will ignite and achieve sustained burning when expsoed to a test flame in accordance with ASTM 92, Standard Test Method for Flash and Fire Points by cleveland open cup tester (NFPA1)
Fire Point
A geometric shape used to depict the four components required for a fire to occur: Fuel, Oxygen, Heat and Chemical Chain Reactions:
Fire Tetrahedron
A geometric shape used to depict the three components of which a fire is composed: Fuel, Oxygen, and Heat
Fire Triangle
The range in concentration between the lower and upper flammable limits (NFPA 67)
Flammable Range
The minimum temperature at which a liquid or a solid emits vapor sufficient to form an ignitable mixture with air near the surface of the liquid or the solid (NFPA 115)
Flash Point
A transition phase in the development of a compartment fire in which surfaces exposed to thermal radiation reach ignition temperature more or less simultaneously, and the fire spreads rapidly throughout the space, resulting in full room involvement or total involvement of the compartment or enclosed space (NFPA 921)
Flashover