fire extinguishers
DESCRIPTION
Fire extinguishers By: Muhammad Iqbal Khan SS Biology Email ID:[email protected] 0923135448175TRANSCRIPT
FIREMuhammad Iqbal KhanSS BiologyEmail ID:[email protected]
INTRODUCTIONINTRODUCTION
Fires can break out any timeFires can break out any time Do you know what to do ?Do you know what to do ? Do you know where to go ?Do you know where to go ? Do you know which extinguisher to Do you know which extinguisher to
use ?use ?
The following slide show will help,The following slide show will help,
HOWEVER YOU SHOULD READ YOUR HOWEVER YOU SHOULD READ YOUR LOCAL FIRE INSTRUCTIONS,LOCAL FIRE INSTRUCTIONS,
IT JUST MIGHT SAVE YOUR LIFE IT JUST MIGHT SAVE YOUR LIFE
OR SOMEONE ELSES.OR SOMEONE ELSES.
IF YOU FIND A FIREIF YOU FIND A FIREOR SMELL BURNING OR SEE OR SMELL BURNING OR SEE
SMOKESMOKE SHOUT,SHOUT, FIRE, FIRE, FIRE,FIRE, FIRE, FIRE, don’t be embarrassed or worried don’t be embarrassed or worried
about being wrong and don’t try to be about being wrong and don’t try to be a hero.a hero.
Press the nearest FIRE CALL BUTTON, Press the nearest FIRE CALL BUTTON, get to know where they are, normally get to know where they are, normally by or close too exits. by or close too exits.
FIRE CALL POINTFIRE CALL POINT
BREAK GLASS TO SOUND ALARM
USE THE NEAREST PHONE AND CALL USE THE NEAREST PHONE AND CALL THE EMERGENCY NUMBER.THE EMERGENCY NUMBER.
GIVE YOURGIVE YOUR NAMENAME WHERE YOU ARE CALLING FROMWHERE YOU ARE CALLING FROM WHERE THE FIRE ISWHERE THE FIRE IS ONLY IF IT IS SAFE TO DO SO - ONLY IF IT IS SAFE TO DO SO -
INFORM THE OPERATOR IF YOU ARE INFORM THE OPERATOR IF YOU ARE MAKING AN ATTEMPT TO EXTINGUISH MAKING AN ATTEMPT TO EXTINGUISH THE FIRE THE FIRE
ONLY TACKLE A FIRE IF IT IS ONLY TACKLE A FIRE IF IT IS SAFE TO DO SOSAFE TO DO SO
LEAVE THE BUILDING BY THE LEAVE THE BUILDING BY THE NEAREST EXIT.NEAREST EXIT.
CLOSE DOORS/ WINDOWS ONLY IF CLOSE DOORS/ WINDOWS ONLY IF SAFE TO DO SOSAFE TO DO SO
GO TO THE FIRE ASSEMBLY POINTGO TO THE FIRE ASSEMBLY POINT AWAIT THE FIRE SERVICEAWAIT THE FIRE SERVICE
REMOVE ONE OR MORE OF THE ELEMENTSREMOVE ONE OR MORE OF THE ELEMENTSREQUIRED TO SUSTAIN COMBUSTION AND THE FIRE REQUIRED TO SUSTAIN COMBUSTION AND THE FIRE
WILL GO OUTWILL GO OUT
Fire ExtinguisherFire Extinguisher Portable device used to put out fires of limited Portable device used to put out fires of limited
size. Such fires are grouped into four classes, size. Such fires are grouped into four classes, according to the type of material that is according to the type of material that is burning.burning.
Class A fires include those in which ordinary Class A fires include those in which ordinary combustibles such as wood, cloth, and paper combustibles such as wood, cloth, and paper are burning.are burning.
Class B fires are those in which flammable Class B fires are those in which flammable liquids, oils, and grease are burning. liquids, oils, and grease are burning.
Class C fires are those involving live electrical Class C fires are those involving live electrical equipment. equipment.
Class D fires involve combustible metals such Class D fires involve combustible metals such as magnesium, potassium, and sodium. Each as magnesium, potassium, and sodium. Each class of fire requires its own type of fire class of fire requires its own type of fire extinguisher.extinguisher.
Some extinguishers will put out only Some extinguishers will put out only one class of fire; others are used for one class of fire; others are used for two or even three classes; none is two or even three classes; none is suitable for all four classes.suitable for all four classes.
Fire extinguishers may go unused for Fire extinguishers may go unused for many years, but they must be many years, but they must be maintained in a state of readiness. For maintained in a state of readiness. For this reason, periodic inspection and this reason, periodic inspection and servicing are required, and that servicing are required, and that responsibility rests with the owner. responsibility rests with the owner. Local Authority Fire department Local Authority Fire department inspectors check at periodic intervals inspectors check at periodic intervals to see that extinguishers are present to see that extinguishers are present where required by law and that they where required by law and that they have been serviced within the have been serviced within the specified time period.specified time period.
Class A fire extinguishersClass A fire extinguishers
Class A fire extinguishers are usually Class A fire extinguishers are usually water based. Water provides a heat-water based. Water provides a heat-absorbing (cooling) effect on the absorbing (cooling) effect on the burning material to extinguish the burning material to extinguish the fire. Stored-pressure extinguishers fire. Stored-pressure extinguishers use air under pressure to expel use air under pressure to expel water. water.
EXTINGUISHERS FOR CLASS EXTINGUISHERS FOR CLASS B FIRES B FIRES
Class B fires are put out by excluding air, by Class B fires are put out by excluding air, by slowing down the release of flammable slowing down the release of flammable vapoursvapours, or by interrupting the chain , or by interrupting the chain
reaction of the combustion. reaction of the combustion. Three types of extinguishing agents —Three types of extinguishing agents — carbon dioxide gas, carbon dioxide gas, dry chemical (powder)dry chemical (powder), and , and foam foam
are used for fires involving flammable are used for fires involving flammable liquids, liquefiable solids, greases, and oils. liquids, liquefiable solids, greases, and oils.
Carbon dioxide is a compressed gas Carbon dioxide is a compressed gas agent that prevents combustion by agent that prevents combustion by displacing the oxygen in the air displacing the oxygen in the air surrounding the fire. surrounding the fire. (CAUTION, DO NOT (CAUTION, DO NOT TOUCH THE HORN OR BASE OF THE TOUCH THE HORN OR BASE OF THE EXTINGUISHER DURING DISCHARGE AS EXTINGUISHER DURING DISCHARGE AS THEY BECOME EXTREMELY COLD)THEY BECOME EXTREMELY COLD)
The two types of dry chemical extinguishers The two types of dry chemical extinguishers include one that contains ordinary sodium or include one that contains ordinary sodium or potassium bicarbonate, urea potassium potassium bicarbonate, urea potassium bicarbonate, and potassium chloride base agents;bicarbonate, and potassium chloride base agents;
The multi-purpose, dry chemical type The multi-purpose, dry chemical type extinguishers contains an ammonium phosphate extinguishers contains an ammonium phosphate based powder. The multi-purpose extinguisher based powder. The multi-purpose extinguisher can be used on class A, B, and C fires. can be used on class A, B, and C fires.
Most dry chemical extinguishers use Most dry chemical extinguishers use stored pressure to discharge the stored pressure to discharge the agent, and the fire is extinguished agent, and the fire is extinguished mainly by the interruption of the mainly by the interruption of the combustion chain reaction. combustion chain reaction.
Foam extinguishers use an aqueous Foam extinguishers use an aqueous film forming foam (AFFF) agent that film forming foam (AFFF) agent that expels a layer of foam when it is expels a layer of foam when it is discharged through a nozzle. It acts discharged through a nozzle. It acts as a barrier to exclude oxygen from as a barrier to exclude oxygen from the firethe fire
EXTINGUISHERS FOR CLASS EXTINGUISHERS FOR CLASS C FIRES C FIRES
The extinguishing agent in a class C fire The extinguishing agent in a class C fire extinguisher must be electrically non-extinguisher must be electrically non-conductive. Both carbon dioxide and conductive. Both carbon dioxide and dry chemicals can be used in electrical dry chemicals can be used in electrical fires. An advantage of carbon dioxide is fires. An advantage of carbon dioxide is that it leaves no residue after the fire is that it leaves no residue after the fire is extinguished. When electrical extinguished. When electrical equipment is not energized, equipment is not energized, extinguishers for class A or B fires may extinguishers for class A or B fires may be used.be used.
EXTINGUISHERS FOR CLASS EXTINGUISHERS FOR CLASS D FIRES D FIRES
A heat-absorbing extinguishing A heat-absorbing extinguishing medium is needed for fires in medium is needed for fires in combustible metals. Also, the combustible metals. Also, the extinguishing medium must not react extinguishing medium must not react with the burning metal. The with the burning metal. The extinguishing agents, known as dry extinguishing agents, known as dry powders, cover the burning metal powders, cover the burning metal and provide a smothering blanket.and provide a smothering blanket.
The extinguisher label gives The extinguisher label gives operating instructions and identifies operating instructions and identifies the class, or classes, of fire on which the class, or classes, of fire on which the extinguisher may be used safely.the extinguisher may be used safely.
USING THE WRONG EXTINGUISHER USING THE WRONG EXTINGUISHER CAN BE DANGEROUSCAN BE DANGEROUS
The extinguisher labelThe extinguisher label
Under EC directives all new extinguishers are Under EC directives all new extinguishers are coloured REDcoloured RED
a coloured band will identify the type of a coloured band will identify the type of extinguisher,extinguisher,
READ THE INSTRUCTIONSREAD THE INSTRUCTIONS
New extinguishers
WATER FOAM POWDER
CO2WATER
FOAM AFFF
POWDER CO2
OLD STYLE COLOURED OLD STYLE COLOURED EXTINGUISHERSEXTINGUISHERS
WATERFOAM AFFF POWDER CO2
