What are the Types of Fire Extinguisher? | Color indicator | Usage
Fire classification
Fires can be placed into
different classes depending on what material is burning. This classification
then gives us information on the type of fire extinguisher we should use to put
out the flames.
Not all fires require the
same type of extinguisher and the correct type has to be used for each blaze.
Different fire extinguisher types are used to differentiate the best ones to
use on the type of fire you are confronting.
Class A
Class A fires are burning
flammable solids as fuel. Examples of these include paper and wood.
Extinguishers that can be used: Water, Foam, ABC Dry powder, Wet chemical
Class B
Class B fires are burning
flammable liquids. Examples include petrol and paint.
Extinguishers that can be used: Foam, CO2 Gas, ABC Dry powder
Class C
Class C fires burn
flammable gases. A couple of examples are propane and butane.
Extinguishers that can be used: ABC Dry powder
Class D
Class D fires are burning
flammable metals. These may include lithium or magnesium.
Extinguishers that can be used: Dry Special Powder
Electrical
Any fire involving
electrical equipment is classed as an electrical fire.
Extinguishers that can be used: CO2 Gas, ABC Dry powder
Class F
Class F fires are burning
cooking oils or fat.
Extinguishers that can be used: Wet chemical
🧯 Water extinguishers
Water
extinguishers are very common and should be used on solid materials only. This
can include paper, wood or any other solid fuel.
Water
based extinguishers are essentially filled with water and use compressed air to
help this come out. Some will also have an additive that will help make them
more effective. They work to cool the fire, removing heat from the fire
triangle and will effectively stop any fire that has started.
Can be used on:
·
Solid fuel fires
Not to be used on:
·
Flammable liquids
·
Flammable gases
·
Flammable metal
·
Electrical fires
·
Cooking oil fires
Water
extinguishers use a red label
🧯 Foam extinguishers
Foam
extinguishers are used on burning liquids such as petrol or diesel fires. They
can also be used on solid fuel fires in the same way as water extinguishers.
Foam
fire extinguishers are actually water based (this is why they can be used on
solid fuels) and have a cooling effect. They also contain ‘Aqueous Film Forming
Foam’ which smothers the fire and seals in any flammable vapours. This will
prevent the fire from reigniting and is why they are used to treat flammable
liquids. Since fire only burns on top of flammable liquids, a foam extinguisher
will create a barrier that smothers the flames.
Can be used on:
·
Solid fuel fires
·
Flammable liquids
Not to be used on:
·
Flammable gases
·
Flammable metal
·
Electrical fires
·
Cooking oil fires
Foam extinguishers use a cream label
🧯 CO2 extinguishers
CO2
extinguishers are typically used on electrical equipment. They can also be used
to extinguish flammable liquids in the same way as foam extinguishers.
Since
CO2 extinguishers are perfect for electrical fires, they are commonly found in
offices or places where there is a lot of electrical devices. They work to
replace the oxygen in the air with CO2 and will smother the fire in order to
put it out. CO2 extinguishers are safe to be used on both high and low voltage
electricals.
Can be used on:
·
Flammable liquids
·
Electrical fires
Not to be used on:
·
Solid fuel fires
·
Flammable gases
·
Flammable metal
·
Cooking oil fires
CO2
extinguishers use a black label
🧯 Dry Powder extinguishers
Dry
Powder extinguishers can be used on most fire types including electrical
devices. Dry Powder fire extinguishers are also known as ABC extinguishers
because they can be used on fire types A, B and C. Specialist ABC extinguishers
can also be used on flammable metals such as magnesium and titanium.
Powder
extinguishers work to coat the fuel source and smother the fire. They will
therefore stop any oxygen from getting to the fuel. Dry Powder extinguishers
should not be used in confined spaces as particles that are released can be
easily inhaled.
Can be used on:
·
Solid fuel fires
·
Flammable liquids
·
Flammable gases
·
Flammable metal
·
Electrical fires
Not to be used on:
·
Cooking oil fires
Dry
powder extinguishers use a blue label
🧯 Wet Chemical Extinguishers
Wet
Chemical extinguishers are specifically designed to be used on fires that have
cooking oils and fats as their fuel. They can also be used on solid fuel fires
but it is more common to use water or foam extinguishers for these.
This
type of extinguisher uses a fine mist that cools flames as well as salts that
form a layer on top of cooking oils. This type of extinguisher both cools and
smothers the fire.
Can be used on:
·
Solid fuel fires
·
Cooking oil fires
Not to be used on:
·
Flammable liquids
·
Flammable gases
·
Flammable metal
·
Electrical fires
Wet
Chemical extinguishers use a yellow label