What is a Water Fire Extinguisher used for?
Water Fire Extinguishers are one the most common types of extinguisher for installation in Class A fire risk areas. In this helpful guide, we explain all about how a Water Extinguisher works to fight fire, when it should and should not be used, and the types of premises that would benefit most from having one on site.
What are the main benefits of a Water Fire Extinguisher?
Water Fire Extinguishers are very cost-effective, as most contain nothing other than plain water! This, in turn, makes them completely environmentally friendly - you don't need to worry about the extinguisher contents flowing into water courses, and no expensive clean up is required. Although simple, Water Extinguishers remain very effective at fighting Class A fires, and is easy to use - even for an untrained person.
Which type of fire can Water Fire Extinguishers be used on?
There are many different types of fire extinguishers. This type of extinguisher is used on Class A fires – those involving flammable solids or carbonaceous materials, including paper, wood and textiles.
How do Water Fire Extinguishers work?
Water Fire Extinguishers remove the 'HEAT' side of the fire triangle. The water has a cooling effect, which lowers the temperature of the burning material when sprayed on it. This makes it impossible for combustion to occur and the flames are rapidly extinguished.
Why do some Water Extinguishers state 'with additive' or 'Water Plus'?
Some Water Extinguishers have a tiny amount of additive in them, called a wetting agent. This additive reduces the surface tension of the water and makes the water droplets literally spread out over the surface of the burning material, massively increasing its effectiveness. This is why 'Water with Additive' or Water Plus Extinguishers often have huge fire ratings compared with standard water.
How are Water Fire Extinguishers identified?
Water Fire Extinguishers have a white band with the word 'Water' in red. On stainless steel, Contempo range and other premium finish extinguishers, the coloured band is red with white lettering.
Where are Water Fire Extinguishers most suitable for use?
With the vast majority of fire risks involving Class A materials, there's almost no premises or building that doesn't need a Class A fire extinguisher. Almost all public or commercial premises need to cover for Class A fires, making Water Fire Extinguishers suitable for offices, warehouses and manufacturing, as well as retail premises, hospitals, hotels, schools and universities or colleges.
What other benefits do Water Extinguishers have?
Despite only being able to extinguish one class of fire (Class A fires), Water Extinguishers remain amongst the most popular fire extinguishers specified. This is because they offer fantastic value for money, and they are very 'clean' in operation - there's comparatively little damage done by a Water Extinguisher, and no chemical additives means no specialist clean-up is required. They are also completely environmentally friendly.
What are the limitations of a Water Fire Extinguisher?
It is extremely dangerous to use a Water Extinguisher on Class B (flammable liquids) and Class F (cooking oil) fires. Not only is the water ineffective, but when the water comes into contact with the hot burning liquid it vapourises instantaneously and literally spreads the fire, making it even worse!
You should also not use a Water Extinguisher on fires involving live electrical equipment. Although most models have been 'dielectrically tested' to 1000V, this is to protect against inadvertent use. Pools of water can form and be lethal to the operator or other persons, even when the fire is extinguished. Water and electricity don't mix well, and we always recommend specifying a properly rated extinguisher, such as a Carbon Dioxide extinguisher, where there is a significant risk of the fire involving live electrical equipment. This is why most fire points have 2 fire extinguishers - one Water/Foam unit and a CO2.