chapter 7 principles of fire
Combustion
A chemical process of oxidation that occurs at a rate fast enough to produce heat and light in the form of fighter a glow or flame
Ventilation Controlled Fire
A fire which the growth is controlled by the amount of air available to the fire.
Endothermic Reaction
A reaction that absorbs heat.
Exothermic Reaction
A reaction that produces heat.
Backdraft
An explosion resulting in the sudden introduction of air into a confined space containing oxygen deficient superheated products of incomplete combustion.
Fuel
Any substance that can undergo combustion.
Flammable
Capable of burning with a flame.
Class D Fire
Combustible Metal fires
Class K Fire
Combustible cooking oils fires
Smoldering
Combustion without flame, usually with incandescence and smoke.
Class C Fire
Energized Electrical Fires
Class B Fire
Flammable Liquid & Gas
Heat
Form of energy characterized by the vibration of molecules and capable of initiating a supporting chemical changes and changes of state.
Convection
Heat transfer by circulation within a medium such as a gas or a liquid.
Radiation
Heat transfer by the way of electromagnetic waves.
Conduction
Heat transfer to another body or within a body by direct contact.
Spontaneous Ignition
Initiation of combustion of a material by an internal chemical or biological reaction that has produced sufficient heat to ignite the material.
Thermal Layering
Is stratification of air and fire gases into layers based on their temperature.
Piloted Ignition Temperature
Minimum temperature a substance should attain in order to ignite.
Class A Fire
Ordinary Combustibles
Pyrolysis
Process in which a material is decomposed, or broken down into simpler molecular compounds by the effects of heat alone; pyrolysis often precedes combustion.
Smoke
The airborne solid and liquid particulates and gases present when a material undergoes pyrolysis or combustion.
Calorie
The amount of heat necessary to heat one gram of water one degree Celsius.
Plume
The column of hot gases, heat, and smoke rising above a fire.
Flameover
The condition where unburned fuel from the original fire as accumulated in the celling layer to a sufficient concentration that it ignites and burns . Typically precedes Flashover.
Temperature
The degree of heat of a body, as measured by a thermometer or similar instrument. Temperature is typically measured in degrees of Celsius or Fahrenheit.
Vapor
The gas phase of a substance
Auto-Ignition Temperature
The lowest temperature at which a combustable material ignites in air without spark or flame.
Flash point
The lowest temperature at which a liquid produces a flammable vapor.
Oxidation
The process by which a substance combines with oxygen.
Air Entrapment
The process of air or gas being drawn into a fire, plume, or jet.
Ignition
The process of initiating self sustained combustion.
British Thermal Unit (BTU)
The quantity of heat required to raise the temp of one pound of water one degree Fahrenheit.
Fire
The rapid oxidation of a fuel producing heat and light.
Heat release rate (HRR)
The rate at which heat energy is generated by burning.
Fire Point
The temperature to which a liquid must be headed in order to sustain burning after the removal of an ignition source. Typically, only a few degrees higher than the flash point.
Heat Transfer
The transport of heat energy from one point to another caused by temperature difference between those points.
Flammable Limits
The upper and lower concentration limit of a flammable gas. The ULE is the upper explosive limit, when the fuel /air is too rich to burn. the LEL is the lower explosive limit, when the fuel/ air is too lean to burn.
Flashover
Transition stage of a fire where all contents in a compartment reach their ignition temperature by thermal radiation and subsequently ignite, resulting in full room involvement. " Flashover is the transition from a fire in a room, to a room on fire."
Fuel Controlled Fire
When the size of the fire is controlled by how much fuel is burning.
