Presentation on theme: "Portable Fire Extinguishers"— Presentation transcript:
1Portable Fire Extinguishers Chapter 8Portable Fire Extinguishers
2Introduction Portable fire extinguishers designed to fight: Small firesUnusual firesFires that cannot be reached quickly with hoselinesFire extinguishers are valuable tools.Four basic PASS stepsFire extinguishers come in a variety of types and sizes.
3Fire Classification and Risk Type of material burning defines class of fire.Classes of fire used to identify type of extinguishers and agentsPre-incident plan for fuel types and locations
4Class A Involves ordinary combustibles Can be extinguished with: WaterWater-based agentsFoamMultipurpose dry chemicalsWater usually the agent used
5Class B Flammable and combustible liquids, gases, and greases Special hazardsCommon extinguishing agents:Carbon dioxideRegular and multipurpose dry chemicalFoam
6Class C Involves energized electrical equipment Water-based agents cannot be used.Turn off electrical power.Categorized with another class of extinguisher: BC or ABCAgents include:Carbon dioxideRegular and multipurpose dry chemicals
7Class D Combustible metals and alloys Erratic behaviour Water and other agents can react violentlyNo universal Class D extinguisher for all metalsClass D agents called dry powders Not to be confused with dry chemicals
8Class K New classification as of 1998 Fires in combustible cooking fuelsAgents usually wet chemicalsAgents used in fixed systems
10Types of Fire Extinguishers Factors for selecting an extinguisher:Type and amount of fuelPerson using extinguisherType of building construction and occupancyType of equipment protectedMain objective extinguishing the fire
12Types of Extinguishing Agents Water is the basic agent for Class A materials.Loaded stream extinguisherWater-based foam extinguishersAqueous film-forming foam (AFFF)Film-forming fluoroprotein foam (FFFP)Better penetration for Class A materialsReduces surface tension of the waterCarbon dioxideInert gas stored under pressure as a liquid capable of being self-expelledDry chemical agentsParticles propelled by gaseous medium
13Kinds of Extinguishers Many types:Small and handheldLarge and require a wheeled cartPump-type extinguishersStored pressure extinguishersCartridge-operated extinguishers
14(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.
15Inner workings of a stored pressure water extinguisher.
16Inner workings of a stored pressure dry chemical extinguisher.
17Inner workings of a carbon dioxide extinguisher with a fixed nozzle.
18Rating Systems for Portable Extinguishers Each class of fuel subjected to a separate type of extinguisher test for its classConducted by independent testing agencyAppropriate ratings and symbolsClass AClass BClass C
19Class C test for electrical conductivity of agent.
20Limitations of Portable Extinguishers Exceeding capabilitiesDesigned for specific purposesFirst-aid method for fire extinguishmentPick the larger sizeWrong class extinguisher may not do the job.
21Portable Extinguisher Operation PASS outlines four simple steps for extinguisher useP: Pull the pinA: Aim the nozzleS: Squeeze the handleS: Sweep the base of the fire
22Care and Maintenance of Portable Extinguishers Simple inspections and careful storage prevent most problemsMove unit from its bracket.Do hand test weight.Do visual check.Recharging water extinguisher a simple process performed by any firefighter
23Re-servicing an Extinguisher (B)(A) Unscrew and remove the top. (B) Add the manufacturer’s recommendation of water. (C) Add foam, if required.8.23
24Re-servicing an Extinguisher (D)(E)(D) Replace the top. (E) Charge the extinguisher with the manufacturer’s recommendation of air.8.24
25Inspection 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.
26Lessons Learned Fire extinguishers can be used as: Initial response toolsTo fight fires in special situationsFirefighters classify fires by their fuels.Four-step process for using an extinguisher: PASS