What are foam extinguishers made of?

It is composed of premix solution (a ratio of water and foam concentrate) mixed with air. It forms a stable foam blanket which spreads above the fuels and adheres to surfaces. Some types of foam forms a film above the fuel surface and seals vapours.

Which chemical is used in extinguisher?

The most common chemical is Sodium Bicarbonate used in the fire extinguisher, and by heating up, it gives carbon dioxide.

What foam is used in fire extinguishers?

Mechanical foam (AFFF) Gas Cartridge Type extinguishers are ideal for installation in outdoor environments. These fire extinguishers are preferred in warehouses, petrol filling areas and factories where there is a dual risk of solid materials and flammable liquid fires….Mechanical Foam (AFFF) Type.

What is chemical foam?

Chemical foam is formed by mixing together a solution of an alkali (usually sodium bicarbonate), an acid (usually aluminum sulfate), water and a stabilizer. The stabilizer is added to make the foam tenacious and long-lived. When these chemicals react, they form a foam or froth of bubbles filled with carbon dioxide gas.

What is the difference between chemical foam and mechanical foam?

Mechanical Foams Mechanical foam is produced by mixing a foam concentrate with water at the appropriate concentration, and then aerating and agitating the solution to form a bubble structure. Therefore, unlike chemical foams, the energy used to create the foam bubbles of a mechanical foam comes from an outside source.

How is fire extinguisher made?

Most of the other elements of a fire extinguisher are made of metal. The pressure vessel is generally made of an aluminum alloy, while the valve can either be steel or plastic. Other components, such as the actuating handle, safety pins, and mounting bracket, are typically made of steel.

What is foam chemical?

foam, in physical chemistry, a colloidal system (i.e., a dispersion of particles in a continuous medium) in which the particles are gas bubbles and the medium is a liquid. The term also is applied to material in a lightweight cellular spongy or rigid form.

How does a foam extinguisher work?

How do AFFF Foam Extinguishers work? Foam Fire Extinguishers provide a fast, powerful means of tackling flammable liquids. They do so by creating a blanket of foam that smothers the fire, cutting of its supply of oxygen of oxygen and contains the flame preventing re-ignition.

How foam is formed in fire extinguisher?

FOAM: A fire fighting foam is simply a stable mass of small air-filled bubbles, which have a lower density than oil, gasoline or water. Foam is made up of three ingredients – water, foam concentrate and air. When mixed in the correct proportions, these three ingredients form a homogeneous foam blanket.

Is fire extinguisher foam toxic?

Safety Concerns Fire extinguishing residues are generally non-toxic, particularly in the amounts you might expect when cleaning up after the use of a portable fire extinguisher.

How does foam extinguish a fire?

How Does Foam Extinguish The Fire. Foam extinguishes Class A Fires by cooling the burning material and removing the heat from the combustion triangle. Foam extinguishes Class B Fires by covering the flammable liquid with a foam blanket, thus cutting off the oxygen supply from the combustion process.

What does a foam extinguisher do?

A foam fire extinguisher discharges a foam solution under pressure that forms a blanket or film on the surface of a burning liquid creating a barrier between the fire vapours and the air necessary to support combustion thereby smothering the fire.

What is a foam extinguisher used for?

Foam fire extinguishers are more versatile than water fire extinguishers as they can be used on both Class A and B (flammable liquids) fires. Foam can also be used to fight electrical fires but it is not recommended as the foam will damage the electrical components.

What is AFFF extinguisher?

Foam (AFFF) Extinguishers. The AFFF fire extinguisher (pronounced A triple F) is suitable for use on class A and B fires. This means that in addition to being able to tackle combustible organic materials such as paper, card, wood and textiles, it is also able to tackle fires involving flammable liquids such as petrol or oils.