Application of Portable Fire Extinguishers

Given a selection of portable extinguishers, full personal protective equipment, and a controlled instructional environment, the student will be able to demonstrate the proper techniques of inspecting, selecting, and using portable extinguishers...


• Wind could disrupt the efficiency of extinguisher

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• Dry chemical portable extinguisher (Class B:C)

• Types

• Cartridge-operated

• Stored-pressure

• Operation

• Cartridge-operated

• Remove hose from its storage position

• Hold extinguisher by carrying handle in one hand

• Depress plunger, keeping your body clear of the filling cap

• Direct nozzle and squeeze control handle with the other hand

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• Stored-pressure

• Break wire seal

• Remove pin

• Hold extinguisher handle with thumb and palm on valve

• Direct nozzle with other hand

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• Advantages

• Interrupt chemical chain reaction

• Distance of 5 to 20 feet - relative distance. The object is to reach but not disturb the fuel source

• For Class B:C

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• Disadvantages

• Size and weight

Notes: Dangerous increases of pressure could occur because of a reaction involving different chemicals.

• Must be refilled with manufacturer=s recommended chemical

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• Hazards: never refill with multi-purpose dry chemical

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• Multi-purpose dry chemical portable extinguishers (Class A:B:C)

• Types

• Cartridge-operated

• Stored-pressure

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• Operation

• Cartridge-operated: same as dry chemical type B:C

• Stored-pressure: same as dry chemical type B:C

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• Advantages

• Interrupts chemical chain reaction

• Prevents combination of air and fuel

• Cools some

• Discharges 5 to 20 feet

• Isolates Class A fires

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• Disadvantages

• Size and weight

• Must be refilled with manufacturer=s recommended chemical

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• Hazards: never refill with regular dry chemical

Notes: Dangerous increases of pressure could occur because of a reaction involving different chemicals.

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• Dry powder portable extinguisher (Class D)

• Operate same as cartridge- operated dry chemical and multi-purpose dry chemicals

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• Advantages

• Forms crust to exclude air and smother fire

Notes: May be discharged from an extinguisher with longer reach, shoveled or scooped on to the fuel source.

• Conducts heat away from fire

• For Class D fires

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• Disadvantage: low effective range 3 to 5 feet - relative distance

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• Hazards: often confused with dry chemical or multi-purpose dry chemical extinguishers

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VI. Limitations of Extinguishers (1-6)

• Have limited discharge distances

• Carry a limited amount of extinguishing agent and requires refill source to recharge

• May be only partially effective or totally ineffective

• Limited discharge time

• Must be maintained and protected from damage

• Expensive to use

• The objective is to reach the fire and extinguish it but not disturb the fuel source

VII. Care and Maintenance (1-7)

• Authority: Article 38A MD Fire Prevention Code and NFPA 10, Standard for Portable Fire Extinguishers

• Frequency

• Maintenance should occur at regular intervals

• Check annually at least

• Follow manufacturers= recommendations for specific type of extinguisher

• Perform a hydrostatic test of pressurized water and CO2 extinguishers every 10 years. Dry chemical every 12 years in accordance with NFPA 10

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• Conditions requiring maintenance

• When found necessary as a result of an inspection

• When the extinguisher has been used

• When there is evidence of tampering

• When there has been physical or mechanical damage

• When it has been exposed to any abnormal temperature, corrosive atmosphere or material

• When it is otherwise impaired as evidenced by leaking, etc.

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