What are fire extinguishers in house and commercial buildings? (IMPORTANT To Know!)

Fire extinguishers are portable devices that help to put out a fire. These devices eject water, gas, foam, or other products to extinguish fires. You can use fire extinguishers in emergencies to put out small fires. If an unfortunate situation arises, you can use fire extinguishers to curb the fire and stop it from causing damage before the fire truck comes.


You will often find fire extinguishers kept in places where a fire breaking out can be fatal, for instance, buildings and transportation. But fire extinguishers are not enough where the fire has spread and is going out of control. It can be challenging to use them so it is important that you read the instructions on them and know the different types of fires.

What are the classes or types of fire?

Did you know there are six different types of fires? And not only that, there are different types of fire extinguishers for different classes of fire. There are six different classes of fire:

Class A

The fire burns on solid materials, like wood, textiles, and paper. Some of these materials have been treated with fire retardants to make it easier to put out the fire.

Class B

The fire uses flammable liquids as fuel, for instance, petrol, oil, and diesel. These can expand very fast and sometimes lead to explosions.

Class C

When any gas has caused the fire. This includes propane, butane and natural gas. A lot of water heaters use natural gas. A smell is added so that it is easier to detect a natural gas leak in your home. If you smell this, it is important to contact your gas supplier. They will turn off the gas and let a plumber come by to get it fixed. Natural gas, propane, and butane can amass and lead to explosions.

Class D

When any metal has caused the fire. Metals can melt if they get too hot. Since they are often used in structural elements of a building, it can collapse.

Class E

Actually, Class E isn’t the name of a class of fire, but we have listed it in this way here to make you remember that ‘Electrical fire’ is a class of fire. Electricity that is not installed properly can cause sparks and fires. We have electric switches to avoid this but an inspector needs to verify that everything is safe.

Class F

When cooking oil causes a fire. Barbequing causes a lot of fires as people are impatient and add too much oil on the fire.

Types of fire extinguishers for house and industrial

There are six major categories of fire extinguishers – water, CO2, foam, powder, wet chemical, and water mist. Each type of fire extinguisher is useful in putting out different classes of fire. Think about what fire extinguishers you might need before buying one. 

Water fire extinguisher 

This fire extinguisher is for Class A fire, i.e. solid fire. Water extinguishers can extinguish fire resulting from wood, textiles, paper, and other solid combustibles. The continuous spray of water helps to reduce the fuel’s ignition temperature.

Additionally, water vapor cuts off the oxygen on the fuel surface. This stops the fuel from burning and the spreading of fire. As you are aware, water conducts electricity. Therefore, you must be careful while keeping it near any electrical equipment. But if it is a di-electrically tested extinguisher, then it is safe on electrical equipment. 

Water extinguishers are of four different types:

  • Water jet extinguisher – When you use this extinguisher, it releases a jet of water on the fire. This jet spray prevents the chances of the fire reigniting by cooling the burning substances.
  • Extinguishers having water with additives – In this extinguisher, the water has foaming chemicals added to it. A small water extinguisher with additives is as effective as a big cylinder having water only. The additives remove the natural surface water tension. This in turn results in the burning materials getting soaked in water easily. 
  • Water spray – This water extinguisher is generally tested on a 35kV electrical source at 1 meter. It tries to put out the fire by spraying fine water droplets surrounded by non-conductive air.
  • Fog or Water mist extinguisher – This extinguisher releases deionized water mist. These are small water droplets. It is helpful in electrical equipment and Class A (solid combustibles), Class B (flammable liquids), and Class C (flammable gasses) fires. In fact, water comes out in the form of fog or mist. But this is the least powerful out of all water extinguishers because the weight of the droplets is very less. This can cause less water damage than the other options.

CO2 fire extinguisher

A CO2 fire extinguisher puts out the fire by releasing carbon dioxide. It is useful in electrical equipment and Class B fire (fire involving petrol paraffin, diesel, etc.) and leaves no residue. This extinguisher is perfect for keeping in server rooms and office buildings. Carbon dioxide cuts the air supply and smothers the fire.

Foam extinguisher

Di- electrically tested AFFF foam extinguishers can be used for electrical equipment. They are most helpful in Class A (solid combustibles) and Class B (flammable liquids) fires.

This adds versatility to foam extinguishers as they can be used on fire involving petrol, wood, diesel, and paper, both solids and liquid fires. It helps in stubbing the fire out by sealing the area around the fire. As a result, the flames can’t reach the air anymore.

Powder fire extinguisher 

Known as ABC fire extinguishers, these are capable of putting out Class A (solid combustibles), Class B (flammable liquids), Class C (flammable gasses), as well as electrical equipment fires. This makes them a multipurpose and versatile fire extinguisher.

When electrical equipment causes a fire, it can reignite because the powder cannot cool a fire. Using this extinguisher in closed spaces like a building should be avoided because it can cause breathing issues and affect visibility. 

Wet chemical extinguisher 

This extinguisher is used for Class A (solid combustibles) fires and also Class B fires(flammable liquids) at times, but it is made for Class F fires. Cooking oils like lard, sunflower oil, butter, olive oil, maize oil, and also fats can cause fire to break out.

The chemicals of this fire extinguisher form a soapy solution by reacting with the burning oil. This cools the burning oil and also acts as a sealant for the surface, eliminating the chance of the fire reigniting.

Identifying different types of extinguishers based on their colors

Seeing the color of the label on the cylinder, you will be able to tell the agent it contains for extinguishing a fire:

  • Water fire extinguishers – The label of this cylinder is bright red.
  • Carbon Dioxide extinguishers – The label on a CO2 cylinder is black.
  • Foam fire extinguishers – This fire extinguisher has a cream-colored label.
  • Powder fire extinguishers – The label color of a dry powder extinguisher is blue.
  • Wet chemical extinguishers – This fire extinguisher carries a yellow-colored label.

To initiate the extinguisher, you have to remove the safety lock first, and then squeeze the handle. Once you do that the content of the cylinder will come out with force through the nozzle.  Each system is unique so read the safety instructions on your fire extinguisher before you use it. Having a fire drill is always a great idea. This makes sure what you have to do when your fire alarm is going off.

To conclude, we can state that fire extinguishers are important safety devices. In your home, there are often explosive gasses such as natural gas. These can lead to fires and we have to be prepared for this. Training can already help you a lot. You also have to make sure that the fire alarm and fire extinguisher are not over the due date. An inspection can help to make sure that everything is up to code.