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

The different types of flames obtained by generating chemical reactions with certain materials.

Since the most remote antiquity, fire has always been both an object of veneration and an object 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 providing us with light, warmth, cooking food and defending us from animals and enemies.

But not all the fires are equal, but there are different classifications with respect to the types of fire that we can come across.. It is on this diversity of typologies on which we are going to speak throughout the present article.

The fire: what is it and how is it generated?

Before specifying the types of fire that exist, it may be useful to stop and reflect on what fire is and how it is generated. Fire, more than an element per se, is the manifestation of a process or a chemical reaction of combustion that is generated in a violent and more or less rapid manner.

It is a process of oxidation at an exothermic level in which a material oxidizes at such a speed that it causes the transmission of light and heat energy, which allows the appearance of flames as a product of gas combustion.

For a flame to form, it is necessary that a series of factors exist and take place without which combustion could not appear. In the first place, a fuel or material with the capacity to ignite under certain circumstances is necessary, which will act as a reducing agent.

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

The third element, of great relevance, is the presence of some kind of energy that allows combustion to start, such as the heat energy generated by friction. Finally, it is necessary for the reaction to be a chain reaction in order to be sustained, otherwise the fire will go out. Flames and fire can be of different shades and colors and have different behaviors depending on what elements are serving as combustion and fuel.

Classification of fire types according to fuel type

One of the most common ways, and in fact the most accepted and official worldwide, of classifying different types of fire can be found in that which takes as a criterion for differentiation the type of fuel involved in the reaction. In this sense, it is divided into five main classes, although sometimes a sixth one has been considered.

Class A

Class A fires are known as all combustion reactions that originate from a combustible fuel. originates from a solid fuel, often of an organic type.. It is the type of fire that we make in bonfires or those provoked in forests or in alive tissues. They can also arise from the combustion of plastics. It is possible to extinguish them with water, either by spraying or spraying, although other methods such as dry powder or carbon dioxide can also be used.

Class B

Class B fires are types of fire which arise from the combustion of flammable liquids 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 candles or old lanterns would belong to this group. Its extinction requires dry powderalthough water spray or CO2 can also be used.

Class C

Class C fires are considered to be all types of fires resulting from the combustion of gases at high temperature, 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 tends to appear more quickly usually appears more quickly than in the case of the previous types of fire.. Reactions of this type require dry powder to extinguish.

Class D

Class D, in terms of types of fire, refers to those combustion reactions in which the fuel is some type of flammable metal or metal powder. Examples are the one 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 a fuel in the form of oil or grease, which is used in cooking equipment. In Europe it was called class F fire, and in English-speaking territories they are known as class K (kitchen or cooking) fires.

Although technically it could correspond to class B, this class was created when it was seen 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). Water extinguishers with some specific components are usually used for extinguishing.

Class E

Although technically it is not usually considered a separate type of fire from the previous ones, but each case would be included in the corresponding type of fuel, it has sometimes been referred to as class E fire type. This classification would include mainly the flames produced by alterations linked to elements that work or through which electricity circulates. The reason for its not being considered as a real class is the fact that in the end what is burned are determined components that belong to previous classes.. To extinguish them requires carbon dioxide extinguishers, never water.