1. Chapter 6— Portable Fire Extinguishers

2. Chapter 6 Lesson Goal
After completing this lesson, the student shall be able to operate portable fire extinguishers effectively & safely

3. Portable Fire Extinguishers
Intended for incipient fires
Quicker to deploy than hoselines
Found in most facilities, i.e. homes, businesses
Require little training to use

4. Portable Fire Extinguishers
Most common fire protection device
Most are re-chargeable
FF’s should not rely on privately–owned fire extinguishers

5. Fire Extinguishment Methods
Smothering
Cooling
Chain breaking
Saponification

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

7. Portable Extinguisher Discharge Mechanisms
All use some form of pressure:
Manual pump
Stored pressure
Pressure cartridge
Cylinder (wheeled units)

8. Fire Classifications
Fire extinguishers classified & rated according to their intended use
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)

9. 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)

10. Fire Classifications
Class C fires — Involve Class A or B fires created by electrical energy
Do not use water or water-based agents until electricity is shut off
Recommended method is to turn off or disconnect electrical power before using appropriate extinguisher
(Continued)

11. Fire Classifications
Class D fires — Involve combustible metals, alloys
Can be identified by bright white sparks & emissions from fire process
Class D, dry powder extinguishers work best
(Continued)

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

13. 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

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

15. 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

16. Stored-Pressure Water Extinguishers
Affected by freezing weather
Loaded stream extinguishers have an anti-freeze added
Not suitable for Class C & D fires
Maximum size is 2A

17. 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.

18. 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)

19. 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)

20. 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)

21. 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
Not suitable for flowing fuels
Most effective on static pools of flammable liquids

22. Clean Agent Extinguishers
Designed to replace halons, & use “clean agents” that discharge as rapidly evaporating liquids that leaves no residue
Nonconductive so can be used on Class C
Approved by U.S. EPA
Halon replacements work by inhibiting the chemical chain reaction

23. Carbon Dioxide (CO2) Extinguishers
Found as both handheld/wheeled units
Most effective in Class B, C fires
Leaves no residue
Have limited reach; gas can be dispersed by wind
(Continued)
Courtesy of Ansul Corp.

24. 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 they are bigger
Courtesy of Badger Fire Protection.

25. Carbon Dioxide (CO2) Extinguishers Hazards
Do not touch horn during discharge
Static electricity shock
Cold injuries
In confined spaces it displaces oxygen

26. Dry Chemical Extinguishers
For Class A-B-C fires and/or Class B-C fires; dry powder used on Class D only
Two types:
Cartridge operated
Stored pressure
(Continued)
Courtesy of Ansul Corp.

27. Dry Chemical Extinguishers
Puts out fire by breaking chemical chain reaction
Two basic chemicals:
Regular B:C-rated
Multipurpose and A:B:C-rated
Courtesy of Ansul Corp.

28. Dry Chemical Extinguishers
Agent
Common Names
Class of Fire
Sodium bicarbonate
Regular
B&C
Potassium bicarbonate
Purple K
Potassium chloride
Super K
Monoammonium phosphate
Multi-purpose
ABC

29. Wheeled Fire Extinguishers
3/25/2017
Wheeled Fire Extinguishers
Large units mounted on wheeled carriages
Typically contain 150 to 350 lbs of extinguishing agent
Indoor use requires wide doorways & aisles
6–29

30. Wheeled Fire Extinguishers
3/25/2017
Wheeled Fire Extinguishers
Long delivery hoses allow operators to attack fire from multiple sides
Usually pressurized by separate cylinders
Installed in special hazard areas
6–30

31. 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
Agent is usually a powder
Note: Dry powder & dry chemical not the same thing
(Continued)

32. 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)

33. Controlling/Extinguishing Metal Fires
Portable extinguishers for Class D come in both handheld & wheeled units
Courtesy of Amerex Corp.
(Continued)

34. Controlling/Extinguishing Metal Fires
Powder must be applied in sufficient depth to completely cover burning area to create smothering blanket
(Continued)

35. 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

36. 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

37. 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

38. Classifications A Rating: Based on 1.25 gallons (5 L) of water
2A = 2.5 gallon (10 L)
B Rating: Based on square foot or square meter
20B = 20 sq ft (1.8 sq m)
C Rating: Bases on electrical shock hazard (no shock, it’s a Class C)

39. Classifications D Rating: Used for metals only, no rating
Must be specific to types of metal
K Rating: Used for hot cooking oil application (deep fryers)

40. 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

41. 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

42. Classification of Fire Extinguishers
3/25/2017
Classification of Fire Extinguishers
COOKING OILS K
6–42
COOKING FATS

43. Classification of Fire Extinguishers
3/25/2017
Classification of Fire Extinguishers
Red slash across pictograph means Do Not Use
Use of the fire extinguisher on this type of fire could be dangerous
6–43

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

45. Extinguisher Selection Factors
Outside conditions
Availability of trained personnel
Ease of handling extinguisher
Life hazard/operational concerns

46. Extinguisher Selection Considerations
Select those that minimize risk to life/ property & 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

47. Extinguisher Check Immediately before use
External condition
Hose/nozzle
Weight
Pressure gauge
After selecting size/type for situation, approach fire from upwind side

48. DISCUSSION QUESTION
Why should you always have an escape route?

49. Fire Extinguisher Operation
Most extinguishers operate in a similar manner
Pick up extinguisher by handles, carry to point of application
(Continued)

50. Fire Extinguisher Operation
Once in position, use PASS method
P — Pull the pin
A — Aim the nozzle at the base of the fire
S — Squeeze handles together
S — Sweep nozzle back & forth
(Continued)

51. 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)

52. 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)

53. Fire Extinguisher Operation
If fire in liquid fuel, it may be necessary to apply foam through hoseline or attack with more than one extinguisher
If more than one extinguisher used, work together & maintain constant awareness

54. Fire Extinguisher Inspections
NFPA 10 & 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)

55. Fire Extinguisher Inspections
Servicing responsibility of property owner/building occupant
FFs should include inspections in building inspection program
(Continued)

56. Fire Extinguisher Inspections
Three factors determine usefulness of fire extinguishers
Serviceability
Accessibility
Simplicity of operation
NFPA 10 describes procedures for hydrostatic testing of cylinders

57. 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)

58. 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

59. 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
(Continued)

60. DISCUSSION QUESTION
How should a defective fire extinguisher be repaired?

61. Damaged Fire Extinguishers
Only slight damage/corrosion & uncertain whether safe — Should be hydrostatically tested
If allowed by SOP, leaking hoses, gaskets, nozzles, & loose labels can be replaced by FFs

62. Obsolete Portable Fire Extinguishers
Since 1969
Manufacturers stopped making inverting-type extinguishers
All extinguishers are carried upright
Manufacturing of extinguishers made of copper or brass with cylinders soft soldered or riveted together discontinued
(Continued)

63. Halon Fire Extinguishers
Included in Montreal Protocol
Damages the ozone
World stopped producing halogens at end of 1993
By 2010 all halons, fixed or otherwise, are to be removed

64. Summary
In many cases, fire extinguishers can control or extinguish small fires in less time than it takes to deploy a hoseline
(Continued)

65. Summary
Even though portable fire extinguishers may be found in many of the homes, apartments, & businesses that must be entered to extinguish fire, FFs should only rely on those carried on the fire apparatus.
(Continued)

66. Summary
To use fire extinguishers safely & effectively, FFs must know capabilities & limitations of the extinguisher — & their own capabilities & limitations — as well as the proper techniques for their application

67. Skills Operate a stored pressure water extinguisher
Operate a dry chemical (ABC) extinguisher
Operate a carbon dioxide (CO2) extinguisher
Clean, service & place a portable fire extinguisher back in service. (Skill Sheet FF-I-101)
Operate a dry chemical wheeled unit (Exercise 2)