Fire: Difference between revisions
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The color of fire can also be different depending on the type of fuel present in the reaction. Butane and Propane usually produce a blue hue when burning, whereas wood fires are usually yellow in color. | The color of fire can also be different depending on the type of fuel present in the reaction. Butane and Propane usually produce a blue hue when burning, whereas wood fires are usually yellow in color. | ||
===Application Vs. Incident=== | |||
==References== | ==References== | ||
Revision as of 10:03, 11 August 2007
Fire is an observable side effect produced by an exothermal chemical reaction. Fire is usually produced as a result of a thermal interaction between oxygen and a fuel source (wood, or gasoline, for example).
The typical steps to create fire are as follows:
- a fuel source is affected by heat until it reaches its ignition temperature
- oxidation occurs; oxygen molecules break down larger molecules into carbon dioxide and water vapour
- this reaction produces a visible, incandescent body of heated gas which sustains the reaction until either the fuel is expended or there is no more oxygen available to the reaction
As long as all three properties of heat, oxygen, and fuel are present a fire will continue to burn. Removing any one of these elements will either remove the ability for a fire to start or will extinguish it.
History
It's hard to say when or where fire was first observed or discovered. Evidence from an excavation in the Benot Ya'aqov region of Israel have turned up burned fragments of flint and wood[1] that date from the Acheulian culture(1.8 mil. to 250,000 years ago), are some of the earliest available records of fire use in Eurasia. Evidence in the form of burnt bone in Africa was additionally discovered in 1986 when Bob Brain discovered a deposit approximately 6 meters thick in Swartkrans[2][3]. This finding possibly predated by a million years a discovery in Zhoukoudian, China, associated with Peking Man (H. erectus) circa 400,000 years ago[4]. Whenever it was actually discovered, fire was an integral part of human culture and survival.
Characteristics
Because fire is an observable effect, the varying properties can be identified. The height of the flame, for example, is usually dependant on the heat release rate of the fuel (the heat available or released(intensity) per square space, usually measured in Kw(Kilowatts) or Mw/sq.m.(Megawatts per square meter)) and the available oxygen consumption given the location of the fire.[5].
The color of fire can also be different depending on the type of fuel present in the reaction. Butane and Propane usually produce a blue hue when burning, whereas wood fires are usually yellow in color.
Application Vs. Incident
References
- ↑ Barach, Jerry (2004-04-30). Earliest evidence of use of fire in Eurasia discovered in Hebrew University Excavations at Benot Ya’aqov. Retrieved on 08-09-2007.
- ↑ Armstrong, Sue (1994). "South Africa - The Missing Pieces". New Scientist: 33.
- ↑ Levin, Eric (2005). "First Campfire Discovered in South Africa". Discover: 44.
- ↑ Weiner, Steve et al (1998). "Evidence for the use of fire at Zhoukoudian, China". Science 281: 251-253.
- ↑ Jones, Sr., Barry R. CFI (05-18-2003). FAQ - Fire and arson, explosions, fire science, forensic engineering, and other fire related topics. Retrieved on 08-10-2007.