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Firefighter I. 61. Chapter 6 Lesson Goal. After completing this lesson, the student shall be able to operate portable fire extinguishers effectively and safely following the policies and procedures set forth by the authority having jurisdiction.. Firefighter I. 62. Specific Objectives. 1.Describe methods by which agents extinguish fire. 2.List mechanisms by which portable extinguishers expel their contents. 3.Distinguish among classifications of fires and the most common agents used to extinguish them. .
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1. Essentials of Fire Fighting,
5th Edition
2. Firefighter I 61 Chapter 6 Lesson Goal After completing this lesson, the student shall be able to operate portable fire extinguishers effectively and safely following the policies and procedures set forth by the authority having jurisdiction.
3. Firefighter I 62 Specific Objectives 1. Describe methods by which agents extinguish fire.
2. List mechanisms by which portable extinguishers expel their contents.
3. Distinguish among classifications of fires and the most common agents used to extinguish them.
4. Firefighter I 63 Specific Objectives 4. Describe types of extinguishers and their common uses.
5. Discuss extinguishers and agents for metal fires.
6. Explain the portable extinguisher rating system.
5. Firefighter I 64 Specific Objectives 7. Describe factors to consider in selecting the proper fire extinguisher.
8. Describe items to check for immediately before using a portable fire extinguisher.
9. Describe the PASS method of application.
6. Firefighter I 65 Specific Objectives 10. Summarize procedures that should be part of every fire extinguisher inspection.
11. Discuss damaged portable fire extinguishers and obsolete portable fire extinguishers.
7. Firefighter I 66 Specific Objectives 12. Operate a stored pressure water extinguisher.
13. Operate a dry chemical (ABC) extinguisher. (Skill Sheet 6-I-2)
14. Operate a carbon dioxide (CO2) extinguisher. (Skill Sheet 6-I-3)
8. Firefighter I 67 Fire Extinguishment Methods Smothering
Cooling
Chain breaking
Saponification
9. Firefighter I 68 Portable Extinguisher Expulsion Mechanisms Manual pump
Stored pressure
Pressure cartridge
10. Firefighter I 69 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
11. Firefighter I 610 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
12. Firefighter I 611 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
13. Firefighter I 612 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
14. Firefighter I 613 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
15. Firefighter I 614 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
16. Firefighter I 615 Stored-Pressure Water Extinguishers Air-pressurized water extinguishers or pressurized water extinguishers
Useful for all types of small Class A fires
17. Firefighter I 616 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
18. Firefighter I 617 Water-Mist Stored-Pressure Extinguishers
19. Firefighter I 618 Wet Chemical Stored-Pressure Extinguishers Specifically designed to control/extinguish Class K fires in deep fryers
Contain special potassium-based low-pH agent to cool/suppress fires in unsaturated cooking oils
20. Firefighter I 619 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
21. Firefighter I 620 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
22. Firefighter I 621 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
23. Firefighter I 622 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
24. Firefighter I 623 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
25. Firefighter I 624 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
26. Firefighter I 625 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
27. Firefighter I 626 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
28. Firefighter I 627 Dry Chemical Extinguishers Two basic types
Regular B:C-rated
Multipurpose and A:B:C-rated
Commonly used dry chemicals
Handheld units
Wheeled units
29. Firefighter I 628 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
30. Firefighter I 629 Controlling/Extinguishing Metal Fires Some powdered agents applied with portable extinguishers, others with shovel or scoop
Appropriate application technique described in manufacturers technical sales literature
31. Firefighter I 630 Controlling/Extinguishing Metal Fires Portable extinguishers for Class D come in both handheld, wheeled units
Regardless of applicator, powder must be applied in sufficient depth to completely cover burning area to create smothering blanket
32. Firefighter I 631 Controlling/Extinguishing Metal Fires Operation
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
33. Firefighter I 632 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
34. Firefighter I 633 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
35. Firefighter I 634 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
36. Firefighter I 635 Identification Two Ways Geometric shapes of specific colors with class letter shown within shape
NFPAฎ 10 recommended Uses pictographs to make selection easier; shows types of fires on which extinguishers should not be used
37. Firefighter I 636 Extinguisher Selection Factors Classification of burning fuel
Rating of extinguisher
Hazards to be protected
Size/intensity of fire
38. Firefighter I 637 Extinguisher Selection Factors Atmospheric conditions
Availability of trained personnel
Ease of handling extinguisher
Life hazard/operational concerns
39. Firefighter I 638 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
40. Firefighter I 639 Extinguisher Check Immediately before use
External condition
Hose/nozzle
Weight
Pressure gauge
After selecting size/type for situation, approach fire from windward side
41. Firefighter I 640 Fire Extinguisher Operation All modern extinguishers operate in similar manner
Pick up extinguisher by handles, carry to point of application
42. Firefighter I 641 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
43. Firefighter I 642 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 to achieve final extinguishment
44. Firefighter I 643 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
45. Firefighter I 644 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
46. Firefighter I 645 Fire Extinguisher Inspections NFPAฎ 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
47. Firefighter I 646 Fire Extinguisher Inspections Servicing responsibility of property owner/building occupant
Firefighters should include inspections in building inspection program
48. Firefighter I 647 Fire Extinguisher Inspections Three factors determine value
Serviceability
Accessibility
Simplicity of operation
NFPAฎ 10 describes procedures for hydrostatic testing of cylinders
49. Firefighter I 648 Parts of Fire Extinguisher Inspections Ensure extinguisher in proper location/accessible
Inspect discharge nozzle
Inspect extinguisher shell
Check for legible operating instructions on nameplate
50. Firefighter I 649 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
51. Firefighter I 650 Damaged Fire Extinguishers Can fail at any time; could result in serious injury
Leaking, corroded, otherwise damaged shells/cylinders should be discarded or returned to manufacturer for repair
52. Firefighter I 651 Damaged Fire Extinguishers Only slight damage/corrosion and uncertain whether safe Should be hydrostatically tested
If allowed by SOP, leaking hoses, gaskets, nozzles, and loose labels can be replaced by firefighters
53. Firefighter I 652 Obsolete Portable Fire Extinguishers In 1969
American manufacturers stopped making inverting-type extinguishers
Manufacturing of extinguishers made of copper or brass with cylinders soft soldered or riveted together discontinued
54. Firefighter I 653 Obsolete Portable Fire Extinguishers Extinguishers using carbon tetrachloride and chlorobromomethane prohibited in workplace
If obsolete extinguishers are discovered and occupant requests, firefighters should follow SOP to dispose of them
55. Firefighter I 654 Halon Fire Extinguishers Included in Montreal Protocol
U.S. stopped producing halogens at end of 1993
Units may still be in service
56. Firefighter I 655 Summary In many cases, fire extinguishers can control or extinguish small fires in less time than it takes to deploy a hoseline.
57. Firefighter I 656 Summary Even though portable fire extinguishers may be found in many of the homes, apartments, and businesses that must be entered to extinguish fire, firefighters should only rely on those carried on the fire apparatus.
58. Firefighter I 657 Summary To use fire extinguishers safely and effectively, firefighters must know capabilities and limitations of the extinguisher and their own capabilities and limitations as well as the proper techniques for their application.
59. Firefighter I 658 Review Questions 1. What are the five classes of fire and what do they involve?
2. What fires are aqueous film forming foam (AFFF) extinguishers most effective on?
3. How do carbon dioxide (CO2) portable extinguishers work?
60. Firefighter I 659 Review Questions 4. What are the three most common combinations for extinguishers with multiple markings?
5. List three factors that affect the selection of the proper portable fire extinguisher.
61. Firefighter I 660 Review Questions 6. What should be checked immediately before using a portable extinguisher?
7. What is the PASS method of application?
8. What procedures should be part of every fire extinguisher inspection?