921 Definitions Flashcards
A rapid oxidation process, which is an exothermic chemical reaction, resulting in the evolution of light and heat in varying intensities
Fire
The flow of electric charge
Current.
the tendency of a material to move or deform permanently to relieve stresses.
Creep
Heat transfer to another body or within a body by direct contact
Conduction
An ignition source that has sufficient energy and is capable of transferring that energy to the fuel long enough to raise the fuel to its ignition temperature.
Competent Ignition Source
The heat, gases, volatilized liquids and solids, particulate matter, and ash generated by combustion
Combustion Products
A chemical process of oxidation that occurs at a rate fast enough to produce heat and usually light in the form of either a glow or flame
Combustion
a liquid that has a closed-cup flash point at or above 37.8°C (100°F).
Combustible Liquid
An instrument that samples air and indicates whether there are ignitible vapors or gases present
Combustible Gas Indicator.
Capable of undergoing combustion
Combustible
A distinct and visible fire effect generally apparent on noncombustible surfaces after combustible layer(s) (such as soot, paint, and paper) have been burned away
Clean Burn
Convex segments of carbonized material separated by cracks or crevasses that form on the surface of char, forming on materials such as wood as the result of pyrolysis or burning
Char Blisters
Carbonaceous material that has been burned or pyrolyzed and has a blackened appearance
Char
A relatively thin layer of flowing hot gases that develops under a horizontal surface as a result of plume impingement and the flowing gas being forced to move horizontally
Ceiling Jet
The circumstances, conditions, or agencies that brought about or resulted in the fire or explosion incident, damage to property, bodily injury, or loss of life.
Cause
The amount of heat necessary to raise 1 gram of water 1°C at the pressure of 1 atmosphere and temperature of 15°C
Calorie
A fire effect realized in gypsum products, including wallboard, as a result of exposure to heat that drives off free and chemically bound water
Calcination of Gypsum
The quantity of heat required to raise the temperature of one pound of water 1°F at the pressure of 1 atmosphere and temperature of 60°F
British Thermal Unit (Btu)
The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed
Bonding
Boiling liquid expanding vapor explosion
BLEVE
The expanding leading edge of an explosion reaction that separates a major difference in pressure between normal ambient pressure ahead of the front and potentially damaging high pressure at and behind the front
Blast Pressure Front
A rounded mass of resolidified metal on the end of the remains of an electrical conductor or conductors that was caused by arcing and is characterized by a sharp line of demarcation between the melted and unmelted conductor surfaces
Bead
A deflagration resulting from the sudden introduction of air into a confined space containing oxygen-deficient products of incomplete combustion
Backdraft.
The lowest temperature at which a combustible material ignites in air without a spark or flame
Autoignition Temperature