Fire
1 - Introduction:
Start fires usually on a small scale because most of them arising start from a little spark because of the neglect to follow the ways of preventing fires, but it quickly spread if not promptly Batafaúha leaving losses and the risk of heavy loss of life and luggage, money and facilities, due to the presence of large quantities of flammable materials in everything that surrounds us things that our presence in various locations and the environment surrounding us in the house and the street, school, workplace and places of pleasure, recreation and other sites, and that if there had been a fire for the rest of us and inflicted heavy losses Bmmtlkatna costs. Therefore we must take preventive measures from the dangers of fires to prevent their occurrence and the elimination of their causes, with the potential to control in case it breaks out and put out as soon as possible with minimal losses.
2 - the principle of fire
The principle of the fire on the basis of sequential chemical reactions between the elements of fire (fuel, heat and oxygen) where they combine Boxgen burning material impact factor of the air temperature of (different degree of the temperature for each substance is called the ignition point)
Therefore, a fire to occur there must be three elements are fuel, heat and oxygen, a so-called triangle of ignition: -
1 - fuel (article):
Any material which is flammable and combustion, regardless of their nature and condition of
There are material in nature in the following cases:
Solid State (wood. Paper. Cloth .... etc.)§
The case of liquid and semi-liquid (such as grease and oils of all kinds. Gasoline. Alcohol ... etc)§
and a gas (butane gas. Alastelln. Methane, etc. ..)§
Divided flammable materials into three sections:
easy flammable materials: It can burn in natural conditions and complete combustion burn.§
Materials ignition difficult: the presence of flame and burning glow, but stop when the dimensions of the combustion source flame them.§
materials non-flammable: Do not burn under normal conditions and need special circumstances to ignite§
2 - Temperature:
Achieve any degree of heat to the extent necessary for the ignition and the source of sparks, flame, friction, sunlight, chemical reactions ... etc..
How to Heat Transfer
Objects exchange heat with the surrounding, ie the temperature in normal circumstances are not fixed any that heat moves from hot body to the body which less than in the temperature and occurs in one of the following means: -
1 - Plug contact:
Transmission of heat conduction are touching directly or through a connector as in the case of tentacles hand to pot hot as it moves heat from the pot to hand over Mosul and different metals in the degree of their ability to connect to some of them are good conductor of heat and some other non-conductor of heat and that heat is transferred in liquids and gases change depending on the density and temperature change.
2 - convection currents:
Transmitted heat in liquids and gases due to the change density depending on the temperature change as it moves by convection currents are moving from bottom to top can be observed convection heat transfer as in the pipeline network of hot water to buildings and chimneys ovens, heaters and the spread of fire in the fire buildings of the lower floors to the top.
3 - Radiation:
Thermal radiation absorbed by some objects and reflected by others Valogesam black or dark absorbs heat more shiny objects or with a polished surface shining and the heat transfer in the air in the form of waves with radiation heat Kalocap light and air does not absorb heat, but transmitted from its source to hit the body as if absorbed by the dark temperature rises If bright or polished surface, it reflects heat into the air.
3 - oxygen:
Available oxygen in the air by air (19-21%).
1 - Introduction:
Start fires usually on a small scale because most of them arising start from a little spark because of the neglect to follow the ways of preventing fires, but it quickly spread if not promptly Batafaúha leaving losses and the risk of heavy loss of life and luggage, money and facilities, due to the presence of large quantities of flammable materials in everything that surrounds us things that our presence in various locations and the environment surrounding us in the house and the street, school, workplace and places of pleasure, recreation and other sites, and that if there had been a fire for the rest of us and inflicted heavy losses Bmmtlkatna costs. Therefore we must take preventive measures from the dangers of fires to prevent their occurrence and the elimination of their causes, with the potential to control in case it breaks out and put out as soon as possible with minimal losses.
2 - the principle of fire
The principle of the fire on the basis of sequential chemical reactions between the elements of fire (fuel, heat and oxygen) where they combine Boxgen burning material impact factor of the air temperature of (different degree of the temperature for each substance is called the ignition point)
Therefore, a fire to occur there must be three elements are fuel, heat and oxygen, a so-called triangle of ignition: -
1 - fuel (article):
Any material which is flammable and combustion, regardless of their nature and condition of
There are material in nature in the following cases:
Solid State (wood. Paper. Cloth .... etc.)§
The case of liquid and semi-liquid (such as grease and oils of all kinds. Gasoline. Alcohol ... etc)§
and a gas (butane gas. Alastelln. Methane, etc. ..)§
Divided flammable materials into three sections:
easy flammable materials: It can burn in natural conditions and complete combustion burn.§
Materials ignition difficult: the presence of flame and burning glow, but stop when the dimensions of the combustion source flame them.§
materials non-flammable: Do not burn under normal conditions and need special circumstances to ignite§
2 - Temperature:
Achieve any degree of heat to the extent necessary for the ignition and the source of sparks, flame, friction, sunlight, chemical reactions ... etc..
How to Heat Transfer
Objects exchange heat with the surrounding, ie the temperature in normal circumstances are not fixed any that heat moves from hot body to the body which less than in the temperature and occurs in one of the following means: -
1 - Plug contact:
Transmission of heat conduction are touching directly or through a connector as in the case of tentacles hand to pot hot as it moves heat from the pot to hand over Mosul and different metals in the degree of their ability to connect to some of them are good conductor of heat and some other non-conductor of heat and that heat is transferred in liquids and gases change depending on the density and temperature change.
2 - convection currents:
Transmitted heat in liquids and gases due to the change density depending on the temperature change as it moves by convection currents are moving from bottom to top can be observed convection heat transfer as in the pipeline network of hot water to buildings and chimneys ovens, heaters and the spread of fire in the fire buildings of the lower floors to the top.
3 - Radiation:
Thermal radiation absorbed by some objects and reflected by others Valogesam black or dark absorbs heat more shiny objects or with a polished surface shining and the heat transfer in the air in the form of waves with radiation heat Kalocap light and air does not absorb heat, but transmitted from its source to hit the body as if absorbed by the dark temperature rises If bright or polished surface, it reflects heat into the air.
3 - oxygen:
Available oxygen in the air by air (19-21%).
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