Fire Classes & Fire Extinguisher Types Explained

Fire Classes & Fire Extinguisher Types Explained

The National Fire Protection Agency defines 5 classes of fires based on the source of fuel in the fire triangle. Fuel is considered any type of combustible material; anything that will burn and sustain the fire.


Class A Fires 

The fuel for class A fires consists of ordinary combustible materials. Wood, paper, cloth, rubber and many plastics are class A fires when they burn. These are all items you have throughout your home! Look around your living room, bedroom, or even your back porch and you'll see that almost everything would be a class A fire if it were to burn.

Class B Fires 

Flammable liquid fires, also known as oil fires are caused by, you guessed it, flammable liquids. Gasoline, kerosene, oil based paints, tars, solvents, alcohols, and flammable gasses like propane are considered class B fires. Look under the kitchen sink or in your cleaning closet and you will find the flammable symbol on a number of your products.

Class C Fires 

Known as electrical fires, these fires involve an electrical component. If there is any electricity, perhaps a powerline or some other electrical equipment, the nature of the fire changes and requires a different type of fire extinguisher. This can also be a common type of home fire, sometimes indirectly. For example, let's say you have a small fire near an electrical outlet. Electricity is not part of the fire, but if you were to use a water fire extinguisher, it could conduct electricity and turn your class A into a class C fire. 

Class D Fires 

Consisting of combustible metals, these fires are not common in home settings. It's unlikely you have magnesium, titanium, zirconium, sodium, or potassium metals in your home. Many devices contain lithium batteries but as long as you dispose of them properly, the risk of a class D fire in your home is low. If you do suspect this kind of fire, we recommend you call the fire department immediately. Class D fires are both rare and require specialized fire fighting equipment and training. They do not represent the type of fire to ever be tackled by a non-professional.

Class K Fires

These fires are caused by cooking oils and fats in cooking appliances. While these could also be considered Class B fires (flammable liquids), the extremely high temperatures and nature of vegetable/animal oils put these in a class on their own. Using a water or pressurized extinguisher can actually accelerate the size and spread of the fire. That's why it is so important to use a class K fire extinguisher rated for these fires.

Choose the Right Fire Extinguisher Type

Different types of fires require different classes of extinguishers. To add to the confusion, there are different extinguishing agents in the extinguisher to put out the fire. With so many options, it can be overwhelming!

Element is a multipurpose fire extinguisher that fights A, B, C & K classes of fire. 

Portable Fire Extinguishers

The easiest and most common kind of extinguisher, portable extinguishers are an important part of your fire safety plan. Most fire extinguishers work by negating one of the three components of fire in the Fire Triangle. They'll try to remove Heat, Fuel, or Oxygen in order to put out a fire. Science has also updated the Fire Triangle to the Fire Tetrahedron to include the chemical reaction between the three as modern extinguishers, like Element, break the chemical reaction of fire on a molecular level to put it out.

Water Fire Extinguishers

The original extinguisher, water extinguishers are highly cooling and remove Heat from the fire triangle of Class A fires. Water only works on class A fires. It is not suitable for use on any other kind of fire because water will not disrupt the Fire Tetrahedron. This is true of water mist extinguishers as well.

Foam Fire Extinguishers

Foam fire extinguishers are suitable for use on Class A and Class B fires. The foam builds up on the surface of burning liquids and flames, cutting off the flow of oxygen while cooling the fire. The residue left by a foam extinguisher is difficult to remove, by design, since it needs to blanket the fire in order to cut off oxygen. Unfortunately, many of these are not Class C fire extinguishers so they cannot be used on energized electrical equipment like your TV or as a car fire extinguisher.

CO2 Fire Extinguishers

Carbon dioxide extinguishers are used for B or C class fires. Pressurized CO2 displaces oxygen quickly and has a cooling effect to extinguish a liquid fire without conducting electricity. The pressurized CO2 quickly disperses so it's not ideal for use on A class fires and since they're pressurized, they can also make kitchen fires worse! 

Wet Chemical Fire Extinguishers

Not always suitable for energized fires, wet chemical extinguishers contain chemicals that create a soapy substance that adheres to cooking oils to extinguish flames and cool on contact. The chemical will seal itself to the oil, preventing reignition. 

Remember, never use water on a grease fire. Water will not adhere to oil and will cause a greater fire risk as it can spread the fire.

Dry Chemical Fire Extinguishers

Dry chemical extinguishers work by covering the fuel in a thin layer of chemical dust, separating the fuel from the oxygen in the air. Similar to Element, the chemical also works to interrupt the chain reaction of fire. Unlike Element, they leave a nasty chemical residue.

Element is the world's smallest and longest lasting fire extinguisher that can be used as a kitchen fire extinguisher, car fire extinguisher, off-road fire extinguisher, RV fire extinguisher, motorcycle fire extinguisher and anywhere else!

Halon Alternative Clean Agent Fire Extinguishers

The NFPA defines a "clean agent" as a gaseous fire suppressant that is electrically nonconducting and does not leave a residue upon evaporation (source). It does not mean it is safe for the environment. Halon, one of the first "clean agents" has been removed from the market because of how much damage it does to the environment. 

Halotron and other Halon alternatives discharge in the combined form of a gas/mist or liquid and they rapidly evaporate with twice the range of CO2 extinguishers. Like Element, they are non-conducting and do not leave a residue upon evaporating so they're not damaging to the environment. Unlike  Element, these agents are more expensive and can be hazardous to humans. "Inhalation of high concentrations of vapor may cause central nervous system effects" (source).

Element Eco-Friendly & Safe Clean Agent Fire Extinguishers

Element fire extinguishers are classified as Clean Agent Fire Extinguishers according to the National Fire Prevention Agency (source). Element is also eco-friendly and safe to use. That puts it in a class of its own for fighting A, B, C, & K fires!


Element Provides The Best Fire Safety Of All Fire Extinguisher Types 

  • Fights All Major Classes: A, B, C, & K

  • Small and Lightweight

  • Non-Toxic & Eco-Friendly

  • Easy To Use

  • Never Expires

  • Zero Fire Extinguisher Maintenance

  • Safe to use around people, pets and will not cause additional damage to your possessions

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