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Fire Basics
Before we identify the types of fire extinguishers,
We need to learn a little about how fire works.
Fire Basics
A fire starts when all of the following occurs simultaneously:
There is a fuel or a combustible material
Enough heat to raise the temperature of the material to its ignition point
Sufficient amount of oxygen to support combustion
A Chemical reaction
Types of Fire
The type of fire that is produced depends on which materials are involved
Types of Fire: Class A
Ordinary Combustibles
paper, cloth, wood, rubber, and many plastics
Types of Fire: Class B
Flammable Liquids
Fires in oils, gasoline, some paints, lacquers, grease, solvents, and other flammable liquids
Types of Fire: Class C
Electrical Equipment
wiring, fuse boxes, energized electrical equipment, computers, and other electrical sources
Types of Fire: Class D
Metals
powders, flakes or shavings of combustible metals such as magnesium, titanium, potassium, and sodium
Types of Fire: Class K
Kitchen Fires
combustible cooking fluids such as oils and fats
Types of Fire Extinguishers
Fire Extinguishers are designed to remove one of the three elements that produce a fire
The Label On Each Fire Extinguisher
Indicates Which Type of Fire It Is Designed To Extinguish
Types of Fire Extinguishers: Water
Types Of Fire Extinguishers: Water
Water Extinguishers
Class A (wood, paper, cloth, rubber, and certain plastics) fires only.
Removes the heat element of the fire triangle.
Don’t use water on flammable liquid or cooking oil fires. Doesn’t Work. There is a big risk of spreading the fire.
Don’t use water on an electrical fire. May cause electrocution if electrical devices are plugged.
Types of Fire Extinguishers: Carbon Dioxide
Types Of Fire Extinguishers: Carbon Dioxide
CO2 Extinguishers
Class B and C (flammable liquid and electrical) fires only.
Takes away the oxygen element of the fire triangle.
CO2is not effective for Class A fires because they may re-ignite after the CO2 fades.
Types of Fire Extinguishers: Dry Chemical
Types Of Fire Extinguishers: Dry Chemical
Dry Chemical Extinguishers
Primarily designed for B and C fires.
May be used on Class A, B, and/or C fires. Ensure label indicates this
Interrupts chemical reaction of the fire triangle.
Coats the fuel with a thin layer of powder which separates the fuel from the oxygen.
Types of Fire Extinguishers: Dry Powder
Types Of Fire Extinguishers: Dry Powder
Dry Powder Extinguishers
Class D (metals) fires.
Separates the fuel element from the oxygen element of the fire triangle.
May not effective for Class A fires because they may re-ignite after the powder fades.
Types of Fire Extinguishers: Wet/Dry Chemical for Kitchen
Types Of Fire Extinguishers: Wet/Dry Chemical for Kitchen
Wet/Dry Chemical Kitchen Extinguishers
Class K (oils and fats) fires.
Only required for commercial cooking system hood and fire suppression system
Separates the fuel element from the oxygen element of the fire triangle.