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A fire hazard is any situation in which there is a greater than normal risk of harm to people or property due to fire . Fire hazards can take the form of ways that fires caneasily start, such as a blocked cooling vent, or overloaded electrical system, ways firescan spread rapidly, such as an insufficiently protected fuel store or areas with highoxygen concentrations, or things which, in a fire, pose a hazard to people, such as

materials that produce toxic fumes when heated or blocked fire exits .

The fire triangle or combustion triangle is a simple model, from the science offirefighting , for understanding the ingredients necessary for most fires . It has largely

been replaced in the industry by the fire tetrahedron , which provides a morecomplete model, also described below.

The triangle illustrates the rule that in order to ignite and burn, a fire re uires threeelements! heat , fuel , and an oxidizing agent , usually oxygen . The fire is prevented orextinguished by removing any one of them. A fire naturally occurs when the elementsare combined in the right mixture "e.g., more heat is needed for igniting some fuels,unless there is concentrated oxygen#.

$ithout fuel , a fire will stop. Fuel can be removed naturally, as where the firehas consumed all the burnable fuel, or manually, by mechanically orchemically removing the fuel from the fire. Fuel separation is an importantfactor in wildland fire suppression, and is the basis for most ma%or tactics.&ther fuels may also be chemically altered to prevent them from burning atordinary temperatures, perhaps as part of a fire'prevention measure.$ithout sufficient heat , a fire cannot begin, and it cannot continue. (eat can

be removed by dousing some types of fire with water) the water turns tosteam, taking the heat with it. *ote that water will actually increase or spreadsome other types of fires "such as combustible metal fires, see comments

below#. +eparating burning fuels from each other can also be an effective wayto reduce the heat. In forest fires, burning logs are separated and placed intosafe areas where there is no other fuel. +craping embers from a burningstructure also removes the heat source. Turning off the electricity in anelectrical fire removes the heat source, although other fuels may have caughtfire and continue burning until the firefighter addresses them and their firetriangles too.$ithout sufficient Oxygen , a fire cannot begin, and it cannot continue.&xygen may be removed from a fire by smothering it with an a ueous foam ,

or some inert gas "e.g., carbon dioxide # or dry chemicals, or by enclosing itwhere the fire will uickly use up all of the available oxygen. A candle snufferuses this principle. &xygen for the fire may also be instantantly consumed, ifonly for a moment, by more sophisticated means such as using explosives tosnuff an oil well gas fire. &nce the gas fire is out, it is not hot enough to startagain, but workers must be extremely careful not to create sparks. See Red

Adair .

http://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Hazardhttp://en.wikipedia.org/wiki/Electricityhttp://en.wikipedia.org/wiki/Fuelhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Toxicityhttp://en.wikipedia.org/wiki/Toxicityhttp://en.wikipedia.org/wiki/Fire_exithttp://en.wikipedia.org/wiki/Firefighterhttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Heathttp://en.wikipedia.org/wiki/Fuelhttp://en.wikipedia.org/wiki/Oxidizing_agenthttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Wildfirehttp://en.wikipedia.org/wiki/Emberhttp://en.wikipedia.org/w/index.php?title=Aqueous_foam&action=edithttp://en.wikipedia.org/w/index.php?title=Aqueous_foam&action=edithttp://en.wikipedia.org/wiki/Inert_gashttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Explosiveshttp://en.wikipedia.org/wiki/Oil_wellhttp://en.wikipedia.org/wiki/Red_Adairhttp://en.wikipedia.org/wiki/Red_Adairhttp://en.wikipedia.org/wiki/Red_Adairhttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Hazardhttp://en.wikipedia.org/wiki/Electricityhttp://en.wikipedia.org/wiki/Fuelhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Toxicityhttp://en.wikipedia.org/wiki/Fire_exithttp://en.wikipedia.org/wiki/Firefighterhttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Heathttp://en.wikipedia.org/wiki/Fuelhttp://en.wikipedia.org/wiki/Oxidizing_agenthttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Wildfirehttp://en.wikipedia.org/wiki/Emberhttp://en.wikipedia.org/w/index.php?title=Aqueous_foam&action=edithttp://en.wikipedia.org/wiki/Inert_gashttp://en.wikipedia.org/wiki/Carbon_dioxidehttp://en.wikipedia.org/wiki/Explosiveshttp://en.wikipedia.org/wiki/Oil_wellhttp://en.wikipedia.org/wiki/Red_Adairhttp://en.wikipedia.org/wiki/Red_Adair

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