Fire Triangle

The interaction of the three equal sides of the fire triangle: heat, fuel and
oxygen, are required for the creation and maintenance of any fire. When there is
not enough heat generated to sustain the process, when the fuel is exhausted,
removed, or isolated, or when oxygen supply is limited, then a side of the triangle
is broken and the fire is suppressed.


The heat source is responsible for the initial ignition of wildland fire, and heat
is also needed to maintain the fire and permit it to spread. Heat allows fire to
spread by removing the moisture from nearby fuel, warming surrounding air,
and preheating the fuel in its path, enabling it to travel with greater ease


Fuel could be defined as any kind of combustible material, and is characterized
by its moisture content, size and shape, quantity, and the arrangement in which
it is spread over the landscape. The moisture content of any fuel will determine
how easily that fuel will burn.


Air contains about 21% oxygen, and most fires require at least 16% oxygen
content to burn. Oxygen supports the chemical processes that occur during a
wildland fire. When fuel burns, it reacts with oxygen from the surrounding air
releasing heat and generating combustion products (i.e. gases, smoke,
particles). This process is known as oxidation

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Smokey the Bear