Portable Fire Extinguishers

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Introduction

 Portable fire extinguishers designed to fight:    Small fires Unusual fires Fires that cannot be reached quickly with hoselines  Fire extinguishers are valuable tools.

 Four basic PASS steps  Fire extinguishers come in a variety of types and sizes.

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Fire Classification and Risk

 Type of material burning defines class of fire.

 Classes of fire used to identify type of extinguishers and agents  Pre-incident plan for fuel types and locations 3

Class A

 Involves ordinary combustibles  Can be extinguished with:  Water  Water-based agents  Foam  Multipurpose dry chemicals  Water usually the agent used 4

Class B

 Flammable and combustible liquids, gases, and greases  Special hazards  Common extinguishing agents:   Carbon dioxide Regular and multipurpose dry chemical  Foam 5

Class C

 Involves energized electrical equipment  Water-based agents cannot be used.

 Turn off electrical power.

 Categorized with another class of extinguisher: BC or ABC  Agents include:  Carbon dioxide  Regular and multipurpose dry chemicals 6

Class D

 Combustible metals and alloys  Erratic behaviour  Water and other agents can react violently  No universal Class D extinguisher for all metals  Class D agents called dry powders  Not to be confused with dry chemicals 7

Class K

 New classification as of 1998  Fires in combustible cooking fuels  Agents usually wet chemicals  Agents used in fixed systems 8

Class K equipment.

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Types of Fire Extinguishers

 Factors for selecting an extinguisher:  Type and amount of fuel  Person using extinguisher  Type of building construction and occupancy  Type of equipment protected  Main objective extinguishing the fire 10

Various types of fire extinguishers.

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Types of Extinguishing Agents

     Water is the basic agent for Class A materials.

Loaded stream extinguisher Water-based foam extinguishers  Aqueous film-forming foam (AFFF)  Film-forming fluoroprotein foam (FFFP)  Better penetration for Class A materials  Reduces surface tension of the water Carbon dioxide  Inert gas stored under pressure as a liquid capable of being self-expelled Dry chemical agents  Particles propelled by gaseous medium 12

Kinds of Extinguishers

 Many types:   Small and handheld Large and require a wheeled cart  Pump-type extinguishers  Stored pressure extinguishers  Cartridge-operated extinguishers 13

(A) (B) (C)

(A) Older versions of fire extinguishers are labeled with colored geometrical shapes with letter designations. (B) Newer fire extinguishers are labeled with a picture label system. (C) Many fire extinguishers can be used to fight more than one type of fire.

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Inner workings of a stored pressure water extinguisher.

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Inner workings of a stored pressure dry chemical extinguisher.

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Inner workings of a carbon dioxide extinguisher with a fixed nozzle.

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Rating Systems for Portable Extinguishers

 Each class of fuel subjected to a separate type of extinguisher test for its class  Conducted by independent testing agency  Appropriate ratings and symbols   Class A Class B  Class C 18

Class C test for electrical conductivity of agent.

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Limitations of Portable Extinguishers

 Exceeding capabilities  Designed for specific purposes  First-aid method for fire extinguishment  Pick the larger size  Wrong class extinguisher may not do the job.

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Portable Extinguisher Operation

 PASS outlines four simple steps for extinguisher use  P: Pull the pin  A: Aim the nozzle  S: Squeeze the handle  S: Sweep the base of the fire 21

Care and Maintenance of Portable Extinguishers

 Simple inspections and careful storage prevent most problems  Move unit from its bracket.  Do hand test weight.  Do visual check.

 Recharging water extinguisher a simple process performed by any firefighter 22

Re-servicing an Extinguisher

(A) (B) (C)

(A) Unscrew and remove the top. (B) Add the manufacturer’s recommendation of water. (C) Add foam, if required.

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Re-servicing an Extinguisher

(D) (E)

(D) Replace the top. (E) Charge the extinguisher with the manufacturer’s recommendation of air.

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Inspection Requirements

 Many fire extinguishers are obsolete.

 Inspection is usually a visual inspection.

 If something does not look right, it should be removed and replaced.

 Extinguishers returned to service should be examined prior to their placement on apparatus.

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Lessons Learned

 Fire extinguishers can be used as:   Initial response tools To fight fires in special situations  Firefighters classify fires by their fuels.

 Four-step process for using an extinguisher: PASS 26