Service Delivery 3

Fire Extinguishers

Aim

To introduce students to the various

types of fire extinguishers and their

differing uses

Learning OutcomesAt the end of the session students will be able to:

• Recognise the extinguisher colour coding scheme

• Describe the principles of operation of portable fire extinguishers

• Recognise extinguisher suitability for individual risks

• Recognise the hazards associated with each extinguisher

• State when it would be suitable to use a fire blanket.

Types of extinguishers

• Water

• Foam

• Dry powder

• Carbon dioxide

• Halon.

Method of pressurisation

• Gas cartridge

• Stored pressure.

Certification.

Items covered by BS EN3

• Duration of discharge

• Hoses and nozzles

• Marking

• Colour coding.

Colour coding.

Water extinguisher

Gas cartridge.

Operating lever

control valve

Cartridge piercer

CO2 cartridge

Discharge tube

White

Hose

Nozzle

Water extinguisher

Stored pressure.

Operating lever

Safety pin

Carrying handle

Control valve

Stored pressure area

Water

Discharge tube

Nozzle

Non-use of water extinguishers

• Do not use on fires involving electricity

• Do not use on flammable liquid fires.

Types of foam extinguisher

• Self-aspirating

• Non-aspirating.

Foam extinguisher

Self-aspirating.

Hose connection

Striker

Carrying handle

CO2 gas cartridge

Discharge tube

Foam solution

Foam branch

Foam application.

Considerations when using foam extinguishers

• Check whether the foam is self-aspirating or non-aspirating

• Check the foam’s suitability for the type of fire, i.e. is it polar resistant

• Do not use on fires involving electricity.

Dry powder extinguishers

Powders can be effective on varying classes of fires;

• Class A

• Class B

• Class C

• Class D

• Or combinations of the above.

Dry powder extinguisher

Gas cartridge.

Operating lever

Carrying handle

CO2 cartridge piercer

Gas inlet tube

CO2 gas cartridge

Powder

Discharge tube

Nozzle

Considerations when using powder extinguishers(1)

• Avoid inhaling powders especially if chloride based

• Beware re-ignition when extinguisher is expended

• Wind and moisture will affect efficiency outdoors

• Visibility will be reduced.

Considerations when using powder extinguishers(2)

• Powders will not penetrate hidden spaces

• Powders always create a mess

• Although they are non-conductors they will damage delicate electrical equipment.

Halon extinguisher

Stored pressure.

Operating leverSafety

pin

nozzle

Stored pressure area

Liquid BCF

Discharge tube

Main uses of halon extinguishers

• Small ‘class B’ or ‘class C’ fires

• Fires involving delicate electrical equipment.

Non-use of halons

Do not use on fires involving;

• Chemicals containing oxygen

• Reactive metals

• Metal hydrides.

Carbon dioxide extinguisher.

Operating lever

Safety pin

Carrying handle

Control valve

CO2 gas

Discharge horn

Flexible high pressure hose

Liquid CO2

Discharge tube

Main uses of carbon dioxide extinguishers

• On small fires involving flammable liquids

• On small fires involving electrical equipment.

Considerations when using carbon dioxide

• Discharge will be noisy

• Visibility may be impaired

• The discharge horn and hose become extremely cold - do not hold them with bare hands

• Owing to the poor cooling effect of carbon dioxide, re-ignition may occur.

Carbon dioxide application.

Fire Blanket.

Confirmation Assessments will be based on this lesson and the corresponding study note

Learning Outcomes

• Recognise the extinguisher colour coding scheme

• Describe the principles of operation of portable fire extinguishers

• Recognise extinguisher suitability for individual risks continued…

• Recognise the hazards associated with each extinguisher

• State when it would be suitable to use a fire blanket.

THE END