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CVFD Training – Portable Fire Extinguishers

CVFD Training – Portable Fire Extinguishers

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CVFD Training – Portable Fire Extinguishers

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  1. CVFD Training – Portable Fire Extinguishers SFFMA Training Objectives: 29-01.01 – 29-01.03

  2. Fire Extinguishment Methods • Smothering • Cooling • Chain breaking • Saponification Firefighter I

  3. DISCUSSION QUESTION Has anyone in the class ever used a portable fire extinguisher to extinguish a fire? Firefighter I

  4. Portable Extinguisher Expulsion Mechanisms • Manual pump • Stored pressure • Pressure cartridge Firefighter I

  5. Fire Classifications • Class A fires — Involve ordinary combustibles • Easily extinguished with water, water-based agents (foam), dry chemicals • Water most common agent used by fire service (Continued) Firefighter I

  6. Fire Classifications • Class B fires — Involve flammable/combustible liquids, gases, greases • Special fire hazards; should not be extinguished until fuel gas shut off • Special-hazard fires get larger as fuel volume increases • Extinguishing agents include carbon dioxide, dry chemical, Class B foam (Continued) Firefighter I

  7. Fire Classifications • Class C fires — Involve Class A or B fires created by electrical energy • Do not use water, water-based agents until electrical energy eliminated • Recommended method is to turn off ordisconnect electrical power before using appropriate extinguisher (Continued) Firefighter I

  8. Fire Classifications • Class D fires — Involve combustible metals, alloys • Can be identified by bright white emissions from combustion process • Class D, dry powder extinguishers work best (Continued) Firefighter I

  9. DISCUSSION QUESTION Why should water-based agents not be used on Class D fires? Firefighter I

  10. Fire Classifications • Class K fires — Involve combustible cooking oils • Examples are vegetable fats that burn at extremely high temperatures • Most fuels found in commercial kitchens; can also be found in private homes • Wet chemicals used in extinguishing systems Firefighter I

  11. Pump-Type Water Extinguishers • Intended for use on small Class A fires only • All operate in similar manner • Equipped with single- or double-acting pump Firefighter I

  12. Stored-Pressure Water Extinguishers • Air-pressurized water extinguishers or pressurized water extinguishers • Useful for all types of small Class A fires (Continued) Firefighter I

  13. Stored-Pressure Water Extinguishers • Often used for extinguishing hot spots • Operation • Water stored in tank w/air or nitrogen • Gauge shows pressurization • Pressure forces water up tube, out hose • Class A foam concentrate sometimes added Firefighter I

  14. Water-Mist Stored-Pressure Extinguishers Use deionized water as agent, nozzles produce fine spray instead of stream Deionized water makes safe for use on energized electrical equipment Fine spray enhances cooling/soaking characteristics, reduces scattering of burning material Firefighter I

  15. Wet Chemical Stored-Pressure Extinguishers • Specifically designed to control/extinguish Class K fires in deep fryers • Contain special potassium-based alkaline agent to cool/suppress fires in unsaturated cooking oils Courtesy of Ansul Corp. Firefighter I

  16. Aqueous Film Forming Foam (AFFF) Extinguishers • Suitable for Class A, Class B fires • Fires/vapors from small liquid fuel spills • Different from stored-pressure water extinguishers • Tank contains specified amount of AFFF concentrate mixed with water • Air-aspirating nozzle aerates solution (Continued) Firefighter I

  17. Aqueous Film Forming Foam (AFFF) Extinguishers • Water/AFFF solution expelled by compressed air or nitrogen • To prevent disturbance of foam blanket, do not apply directly onto fuel; allow to rain onto surface/deflect off object (Continued) Firefighter I

  18. Aqueous Film Forming Foam (AFFF) Extinguishers • When AFFF/water mixed, finished foam floats on fuels lighter than water • Vapor seal created by film of water extinguishes flame, prevents reignition (Continued) Firefighter I

  19. Aqueous Film Forming Foam (AFFF) Extinguishers • Foam has good wetting, penetrating properties on Class A fuels; ineffective on polar solvents • Not suitable for fires in Class C, D fuels • Most effective on static pools of flammable liquids Firefighter I

  20. Clean Agent Extinguishers • Designed as replacement for Halon 1211, use “clean agents” that discharge as rapidly evaporating liquids that leaves no residue • Cool/smother fires in Class A, B fuels • Nonconductive so can be used on Class C • Approved by U.S. EPA Firefighter I

  21. Carbon Dioxide (CO2) Extinguishers • Found as both handheld/wheeled units • Most effective in Class B, C fires • Have limited reach; gas can be dispersed by wind (Continued) Courtesy of Ansul Corp. Firefighter I

  22. Carbon Dioxide (CO2) Extinguishers • Carbon dioxide stored under its own pressure as liquefied gas ready for release at any time • Wheeled units similar to handheld except wheeled are considerably larger Courtesy of Badger Fire Protection. Firefighter I

  23. DISCUSSION QUESTION What is the danger of touching the horn on a carbon dioxide extinguisher shortly after it has been used? Firefighter I

  24. Dry Chemical Extinguishers • For Class A-B-C fires and/or Class B-C fires; dry powder used on Class D only • Commonly used today (Continued) Courtesy of Ansul Corp. Firefighter I

  25. Dry Chemical Extinguishers • Two basic types • Regular B:C-rated • Multipurpose and A:B:C-rated • Commonly used dry chemicals • Handheld units • Wheeled units Courtesy of Ansul Corp. Firefighter I

  26. DISCUSSION QUESTION What happens when water is applied to a combustible metal fire? Firefighter I

  27. Controlling/Extinguishing Metal Fires • Special extinguishing agents, application techniques developed to control/extinguish metal fires • No single agent controls/extinguishes fires in all combustible metals (Continued) Firefighter I

  28. Controlling/Extinguishing Metal Fires • Some powdered agents applied with portable extinguishers, others with shovel or scoop • Appropriate application technique described in manufacturer’s technical sales literature (Continued) Firefighter I

  29. Controlling/Extinguishing Metal Fires • Portable extinguishers for Class D come in both handheld, wheeled units Courtesy of Amerex Corp. (Continued) Firefighter I

  30. Controlling/Extinguishing Metal Fires • Regardless of applicator, powder must be applied in sufficient depth to completely cover burning area to create smothering blanket (Continued) Firefighter I

  31. Controlling/Extinguishing Metal Fires • If small amount of burning metal on combustible surface, fire should be covered with powder • 1 to 2 inch (25 to 50 mm) layer spread nearby, burning metal shoveled onto layer • After extinguishment, material left undisturbed until cooled Firefighter I

  32. Portable Extinguisher Rating System • Portable extinguishers classified according to types of fire they extinguish • Class A, B also rated according to performance capability • System based on tests by UL, ULC Firefighter I

  33. Classifications • Class A — From 1-A through 40-A • Class B — From 1-B through 640-B • Class C — No tests • Class D — Test fires vary • Class K — Recognized by UL, ULC since 1996 Firefighter I

  34. Multiple Markings • Extinguishers for more than one class of fire identified by combinations of A, B, and/or C or symbols for each class • Most common are A-B-C, A-B, B-C • All must be labeled appropriately • Unlisted units should not be used • Ratings for each class are independent Firefighter I

  35. Identification — Two Ways • Geometric shapes of specific colors with class letter shown within shape • NFPA® 10 recommended — Uses pictographs to make selection easier; shows types of fires on which extinguishers should not be used Firefighter I

  36. Extinguisher Selection Factors • Classification of burning fuel • Rating of extinguisher • Hazards to be protected • Size/intensity of fire (Continued) Firefighter I

  37. Extinguisher Selection Factors • Atmospheric conditions • Availability of trained personnel • Ease of handling extinguisher • Life hazard/operational concerns Firefighter I

  38. Extinguisher Selection Considerations • Select those that minimize risk to life/property and are effective in extinguishing the fire type • Dry chemical extinguishers should not be selected for use in areas where highly sensitive computer equipment is located Firefighter I

  39. Extinguisher Check • Immediately before use • External condition • Hose/nozzle • Weight • Pressure gauge • After selecting size/type for situation, approach fire from windward side Firefighter I

  40. DISCUSSION QUESTION Why should you always have an escape route? Firefighter I

  41. Fire Extinguisher Operation • All modern extinguishers operate in similar manner • Pick up extinguisher by handles, carry to point of application (Continued) Firefighter I

  42. Fire Extinguisher Operation • Once in position, use PASS method • P — Pull the pin • A — Aim the nozzle • S — Squeeze handles together • S — Sweep nozzle back and forth (Continued) Firefighter I

  43. Fire Extinguisher Operation • Be sure agent reaches fire • Apply agent from point where stream reaches but does not disturb fuel • After fire knocked down, move closer for final extinguishment (Continued) Firefighter I

  44. Fire Extinguisher Operation • If extinguishment not achieved after entire extinguisher discharged, withdraw/reassess • If fire is in solid fuel reduced to smoldering phase, may be overhauled using appropriate tool (Continued) Firefighter I

  45. Fire Extinguisher Operation • If fire in liquid fuel, it may be necessary to apply foam through hoseline or simultaneously attack with more than one extinguisher • If more than one extinguisher used simultaneously, work in unison and maintain constant awareness Firefighter I

  46. Fire Extinguisher Inspections • NFPA® 10 and most fire codes require portable extinguishers inspected at least once/year • Verify that extinguishers • Are in designated locations • Not tampered with or activated • No obvious damage/other condition (Continued) Firefighter I

  47. Fire Extinguisher Inspections • Servicing responsibility of property owner/building occupant • Firefighters should include inspections in building inspection program (Continued) Firefighter I

  48. Fire Extinguisher Inspections • Three factors determine value • Serviceability • Accessibility • Simplicity of operation • NFPA® 10 describes procedures for hydrostatic testing of cylinders Firefighter I

  49. Parts of Fire Extinguisher Inspections • Ensure extinguisher in proper location/accessible • Inspect discharge nozzle • Inspect extinguisher shell • Check for legible operating instructions on nameplate INACCESSIBLE (Continued) Firefighter I

  50. Parts of Fire Extinguisher Inspections • Check locking pin, tamper seal • Determine whether full of agent, fully pressurized • Check for date of previous inspection • Examine condition of hose/fittings • If any items deficient, remove from service Firefighter I