The 6 types of fire, their characteristics, and how they appear

Since the remotest antiquity, fire has always been both an object of veneration and of fear and dread. This double vision of flames comes from the fact that we are aware that fire is an element with the capacity to destroy, but also that it has facilitated our survival by allowing us to light up, get warm, cook food and defend ourselves from animals and enemies.

But not all fires are the same, but there are different classifications regarding the types of fire that we can come across. It is about this diversity of typologies that we are going to talk about throughout this article.

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Fire: what is it and how is it generated?

Before going into specifying the types of fire that exist, it may be useful to stop and reflect on what fire is and the way in which it is generated. Fire, more than an element per se, is the manifestation of a combustion process or chemical reaction that is generated violently and more or less quickly.

It is an exothermic oxidation process

in which a material oxidizes at such a speed that it causes the transmission of light and heat energy, something that allows the appearance of flames as a product of combustion gas.

In order for a flame to form, a series of factors must exist and occur. without which the combustion could not come to appear. In the first place, a fuel or material with the ability to ignite under certain circumstances is necessary, which will act as a reducing agent.

In addition to this, another of the essential requirements is an oxidizer or material/element capable of causing combustion (the most common is oxygen). In this sense, the oxidizer will play the role of oxidizing agent

The third element, of great relevance, is the presence of some type of energy that allows combustion to start, such as heat energy generated by friction. Finally, the chain reaction needs to be in order to be sustained, or else the fire will go out. Flames and fire can be of different shades and colors and have different behaviors depending on which elements are serving as oxidizer and fuel.

Classification of types of fire according to the type of fuel

One of the most common ways, and in fact the most accepted and official worldwide, of classifying different types of fire we can find it in the one that takes as a differentiation criterion the type of fuel that participates in the reaction. In this sense it is divided into five main classes, although on occasions it has come to be considered a sixth.

A class

All those combustion reactions that originates from a solid fuel, and often of an organic type. It is about the type of fire that we make in bonfires or those caused in forests or in living tissues. They can also arise from the combustion of plastics. It is possible to extinguish them with water, either jet or spray, although other methods such as dry powder or carbon dioxide can also be used.

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Class B

Class B fires are types of fire which appear from the combustion of liquid materials with flammable capacity, or solids with the capacity to liquefy. It is the type of fire that is produced by the combustion of alcohol, gasoline, wax or paint, among others. In this sense, the fire of the candles or old lanterns would belong to this group. Its extinction requires dry powder, although water spray or CO2 can also be used.

C-class

Class C fires are considered to be the set of types of fire that are the product of the combustion of gases at high temperatures, such as those used in electrical appliances or in the kitchen. Thus, the combustion of methane or natural gas would produce this type of fire, which It usually appears faster than in the case of the previous ones.. Reactions of this type require dry powder to quench.

Class D

Class D, in what refers to the types of fire, refers to those combustion reactions in which the fuel is some type of metal or flammable metal powder. Examples of this are caused by magnesium. They should not be extinguished with water since the reaction is extremely virulent, but special powder extinguishers should be used.

Class F or K fires

This last type of fire is somewhat special, since it refers to a fire started by fuel in the form of oil or fat, which is used in kitchen equipment. In Europe it was called class F fire, and in English-speaking territories they are known as class K fires (from kitchen or kitchen).

Although technically it could correspond to those of class B, this class was created when seeing that the behavior of the flames and the type of elements that can be used to extinguish them are different (for example, it could not be extinguished with carbon dioxide). To put out, water extinguishers with some specific components are usually used.

E-class

Although technically it is not usually considered a type of fire apart from the previous ones, rather each case is would be included in the type of fuel that corresponds, on occasions there has been talk of the type of class fire AND. This classification would mainly include flames produced by alterations linked to elements that work or through which electricity flows. The reason for not considering it as a real class is the fact that basically what is burned are certain components that belong to previous classes. Putting them out requires carbon dioxide extinguishers, never water.