Fire Extinguishers

Usually fires any larger than the size of a waste paper bin should not be attempted to be extinguished but if smaller it might be benficial to use the extinguisher. However, you should only consider using a fire extinguisher if all members of your business have been alerted to the fire and the fire department has been called. Also, make sure you are safe from smoke and that the fire is not between you and your only escape route. 

Different types of fire extinguisher – a detailed guide

Water Extinguishers

Overview: Water fire extinguishers are the most common extinguisher type for class A fire risk. Most premises will require either water or foam extinguishers.

Label Colour:
– Bright Red

Use for:
– Organic materials such as:
o Paper and cardboard
o Fabrics and textiles
o Wood and coal

Do not use for:
– Fires involving electrical equipment
– Kitchen fires
– Flammable gas and liquids

How water extinguishers work:
The water has a cooling effect on the fuel, causing it to burn much more slowly until the flames are eventually extinguished.

Types of premises/business who may need water extinguishers:
– Buildings constructed of wood or other organic materials
– Premises where there are organic materials to be found such as:
o Offices
o Schools
o Hospitals
o Residential properties
o Warehouses

In fact, most buildings need either water or foam extinguishers.

Where to locate water extinguishers:
– By the exits on a floor where a Class A fire risk has been identified

Foam Extinguishers

Overview:
Foam fire extinguishers are the most common type of extinguisher for Class B fires, but also work on Class A fires as they are water-based.

Label Colour:
– Cream

Use for:
– Organic materials such as:
o Paper and cardboard
o Fabrics and textiles
o Wood and coal
Plus:
– Flammable liquids, like paint and petrol

Do not use for:
– Kitchen fires
– Fires involving electrical equipment
– Flammable metals

How foam extinguishers work:
As with water extinguishers, foam extinguishers have a cooling effect on the fuel. On burning liquids, the foaming agent creates a barrier between the flame and the fuel, extinguishing the fire.

Types of premises/business who may need Foam extinguishers:
– Buildings constructed of wood or other organic materials
– Premises where there are organic materials to be found such as:
o Offices
o Schools
o Hospitals
o Residential properties
o Warehouses
– Buildings where flammable liquids are stored

In fact, most buildings need either water or foam extinguishers

Where to locate foam extinguishers:
– By the exits on a floor where a Class A or Class B fire risk has been identified

Dry Powder Extinguishers

Overview:
Standard dry powder fire extinguishers are also called ‘ABC’ extinguishers because they tackle class A, B and C fires, however, they are not recommended for use in enclosed spaces. This is because the powder can be easily inhaled, and also the residue is very difficult to clean up after. ABC powder extinguishers can also be used on some electrical fires. Specialist dry powder extinguishers are used for flammable metals.

Label Colour:
– Blue

Use for:
– Organic materials such as:
o Paper and cardboard
o Fabrics and textiles
o Wood and coal
Plus:
– Flammable liquids, like paint and petrol
Plus:
– Flammable gases, like liquid petroleum gas (LPG) and acetylene
Plus:
– Fires involving electrical equipment up to 1000v

Specialist dry powder extinguishers are only used on flammable metals, such as titanium and magnesium.

Do not use for:
– Fires involving cooking oil
– Fires involving electrical equipment over 1000v
– or in enclosed spaces, such as offices or residential properties

How dry powder extinguishers work:
Dry powder extinguishers smother fires by forming a barrier between the fuel and the source of oxygen.

Types of premises/business who may need Dry Powder extinguishers:
– Businesses using flammable gases for chemical processes
– Premises where welding and flame cutting takes place
– Garage forecourts
– Liquid petroleum gas (LPG) dispensing plants
– Premises with large, commercial boiler rooms

Where to locate Dry Powder extinguishers:
– Place dry powder extinguishers near to the source of the fire risk.

Carbon Dioxide (CO2) Extinguishers

Overview:
CO2 fire extinguishers are predominantly used for electrical fire risks and are usually the main extinguisher type provided in computer server rooms. They also put out Class B fires (flammable liquids, such as paint and petroleum).

Label Colour:
– Black

Use for:
– Flammable liquids, like paint and petrol
– Electrical fires

Do not use for:
– Kitchen fires – especially chip-pan fires
– Combustible materials like paper, wood or textiles
– Flammable metals

How CO2 extinguishers work:
CO2 extinguishers suffocate fires by displacing the oxygen the fire needs to burn.

Types of premises/business who may need CO2 extinguishers:
– Premises with electrical equipment, such as:
o Offices
o Kitchens
o Construction sites
o Server rooms

All work vehicles should also carry a smaller 2kg CO2 extinguisher.

Where to locate CO2 extinguishers:
– Place near to the source of the fire risk and/or near the fire exits.

Wet Chemical Extinguishers

Overview:
Wet Chemical fire extinguishers are designed for use on Class F fires, involving cooking oils and fats.  They can also be used on Class A fires although it is more common to have a foam or water extinguisher for this type of fire risk.

Label Colour:
– Yellow

Use for:
– Cooking oil/fat fires
– Organic materials such as:
o Paper and cardboard
o Fabrics and textiles
o Wood and coal

Do not use for:
– Flammable liquid or gas fires
– Electrical fires
– Flammable metals

How wet chemical extinguishers work:
Wet chemical extinguishers create a layer of foam on the surface of the burning oil or fat, preventing oxygen from fuelling the fire any further. The spray also has a cooling effect.

Types of premises/business who may need wet chemical extinguishers:
– Commercial kitchens
– Canteens

Where to locate wet chemical extinguishers:
– Place near to the source of the fire risk.