Which is a common dry chemical extinguishing agent?

Views: 28     Author: Site Editor     Publish Time: 2023-03-10      Origin: Site

This type of fire extinguisher is purposely designed for handling fire involving liquids that are flammable, electrical equipment, or metals that are combustible.  They can be used against different categories of fires, depending on the chemical agent they carry.  Always check to ensure you are using an extinguisher on the fire(s) it was designed to fight; otherwise, you might end up with a bigger mess.

dry chemical powder

Types of agents used in dry extinguishers

Various kinds of dry chemical extinguishers are available, each purposely allocated for a specific fire type. It's wise to use the appropriate extinguisher for the type of fire! Using the wrong agent can cause fire to reemerge after it appears to have been extinguished effectively. Herein are some of the agents applied in dry extinguishers.

Sodium Bicarbonate

Sodium Bicarbonate is the most commonly used dry chemical extinguishing substance. It is also called BC because it's effective against Class B and C flames. It forms a dense blanket of particles that hampers the combustion of flammable gases and liquids. It does so by heating up and emitting a cloud of carbon dioxide, which suffocates the fire, starving it of oxygen and disrupting the chemical reaction needed to continue burning. However, it is not appropriate for Class A fires since it does not decrease the heat from the fire, preventing the burning substances from reflashing.

Monoammonium Phosphate

MAP is a chemical substance used in multipurpose or ABC fire extinguishers to put out Class A, B, and C flames. It forms a barrier between air and fuel and absorbs heat, keeping the flaming materials from reflashing. It is the most commonly used dry chemical extinguisher, especially in the oil and gas fields. It's also the only ARFF-certified dry chemical agent. Of course, ARFF is short for Aircraft Rescue and Fire Fighting.

Potassium Bicarbonate

Potassium Bicarbonate is another chemical powder used in dry fire extinguishers designed to put out Class B and C flames. It creates a thin, insulating layer of particles that prevents flammable gases and liquids from burning.

Potassium Chloride

Potassium chloride, purple K, puts out Class B and C flames. It creates a thick, insulating layer of nanoparticles that prevents flammable gases and liquids from burning.

How Do Dry Chemical Extinguishers Work?

All dry chemical extinguishers work by forming an insulating shield between the air and the fuel. This barrier stops the fire from receiving oxygen, causing it to burn out. The shield also absorbs heat, which aids in keeping the fire from growing. Furthermore, some dry chemical fire fighting solutions form a dense film of particles interrupting the fire's chemical reaction, essentially putting out the flames.

Some dry chemical extinguishers also create a thin, protective blanket of particles that disrupt the thermal reaction of flammable gases and liquids. This helps contain the flames, keeping the fire from reaching other areas of a property.

Advantages of Dry Chemical Extinguishing Agents

The most apparent advantage of dry chemical fire fighting solutions is their ability to extinguish fires quickly and effectively. They are also reasonably priced and simple to use. Furthermore, they only cause minimal harm to the environment and the fire scene, making them a safer option.


Dry chemical extinguishers are widely used today. They are created to extinguish fires involving electrical equipment, flammable liquids, and combustible metals as soon as possible. There are many different types of dry chemical extinguishing substances, each intended for a specific type of fire. They work by forming a barrier between the air and the fuel, which keeps out oxygen, interferes with the flame's chemical processes, and might also absorb heat.

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