what is fire ?
Fire is the burning of combustible material. A fire in an unwanted place and on an unwanted occasion and in uncontrollable quantity can cause damage or destroy property and materials. Fires injure people, and sometimes, cause loss of life. Hence, every effort must be made to prevent fire. When a fire outbreak is discovered, it must be controlled and extinguished by immediate correct action.
IGNITION TEMPERATURE -:The minimum temperature at which different substances catches fire is known as ignition temperature.
Components of fire?
The factors that must be present in combination for a fire to continue to burn are as follows.
Fuel -: Any substance, liquid, solid, or gas will burn if given oxygen and high enough temperature.
Heat -: Every fuel will begin to burn at a certain temperature. Solids and liquids give off vapour when heated and it is this vapour which ignites. Some liquids give off vapour even at normal room temperature
eg. petrol.
Oxygen-: Usually it exists in sufficient quantity in air to keep a fire burning
Fire triangle –:Representation of three component of fire(heat, fuel and oxygen) at three adjacent side of a triangle is known as fire triangle
Extinguishing of fire -:
isolating or removing any of these factors from the combination will extinguish the fire. There are three basic
ways of achieving this.
• Starving -: The fire of fuel by removing the fuel in the vicinity of fire.
• Smothering – : By isolating the fire from the supply of oxygen by blanketing it with foam, sand etc.
• Cooling – : By using water to lower the temperature.
PREVENTING FIRE-:
The majority of fires begin with small outbreaks which burn unnoticed until they become big fires of controllable magnitude. Most of the fires could be prevented with more care and by following some rules of simple common sense.
Accumulation of combustible refuse (cotton waste soaked with oil, scrap wood, paper, etc.) in odd corners are of fire risk. Refuse should be removed to collection points.
The cause of fire in electrical equipment is misuse or neglect. Loose connections, wrongly rated fuses or cables,
overloaded circuits cause over heating which may in turn lead to fire. Damage to insulation between conductors in cables also causes fire.
Clothing and anything else which might catch fire should be kept well away from heaters. Make sure the heater is shut off at the end of a working day.
Highly flammable liquids and petroleum mixtures (Thinner ,Adhesive solutions, Solvents, Kerosene, Spirit, LPG Gas etc.) should be stored in a separated place called the flammable material storage area.
Blowlamps and torches must not be left burning when they are not in use.
CLASSIFICATION OF FIRE-:
CLASS ‘A’ FIRE -:Fire on woods ,clothes ,paper and solid materials known as class ‘A’ fire
CLASS ‘B’ FIRE -: Fire on flammable liquids like petrol, diesel, kerosene and gasoline is known as class ‘B’ fire
CLASS ‘C’ FIRE -: Fire on gas and LPG gas is known as class ‘C’ fire
CLASS ‘D’ FIRE -:Fire on solid metals like electrical equipment’s called class ‘D’ fire