320 likes | 460 Views
Service Delivery 3. Fire Extinguishers. Aim. To introduce students to the various types of fire extinguishers and their differing uses. Learning Outcomes At the end of the session students will be able to:. Recognise the extinguisher colour coding scheme
E N D
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.
Items covered by BS EN3 • Duration of discharge • Hoses and nozzles • Marking • Colour coding.
Operating lever control valve Cartridge piercer CO2 cartridge Discharge tube White Hose Nozzle Water extinguisherGas cartridge.
Operating lever Safety pin Carrying handle Control valve Stored pressure area Water Discharge tube Nozzle Water extinguisherStored pressure.
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.
Striker Hose connection Carrying handle CO2 gas cartridge Discharge tube Foam branch Foam solution Foam extinguisher Self-aspirating.
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.
Operating lever Carrying handle CO2 cartridge piercer Gas inlet tube CO2 gas cartridge Powder Discharge tube Nozzle Dry powder extinguisherGas cartridge.
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.
Safetypin Operating lever nozzle Stored pressure area Liquid BCF Discharge tube Halon extinguisherStored pressure.
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.
Operating lever Safety pin Carrying handle Control valve Flexible high pressure hose CO2 gas Liquid CO2 Discharge horn Discharge tube Carbon dioxide extinguisher.
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.
ConfirmationAssessments 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.