Fire & Fire extinguisher Classifications With Fire Spread Methods

 

Fire & Fire extinguisher Classifications and Fire Spread Methods

Classification of fire and fire extinguishers

Types of fire and extinguishing

Class A: A type fire consisting of solid materials such as wood, paper, cardboard, textiles, furniture, and plastics that are usually shiny during combustion. This type of fire is extinguished by cooling which is obtained by using water.

Class B: The fire that involves liquids or liquid solids such as paint, oil or grease. They can be further subdivided:

      Class B1: Fires that contain liquids that are soluble in water, such as methanol. They can be extinguished with carbon dioxide, dry powder, water spray, and mild water and vapor liquids.

      Class B2: Types of fire that contains

water-soluble liquids, such as gasoline and oil. They can be extinguished using foam, carbon dioxide, dry powder, mild water and vapor liquid.

Class C: Fires are caused by gases such as natural methods of extinction or liquid gases such as butane or propane. Foam or dry powder can be extinguished with water to cool any container included or nearby.

Class D: Fires start with metals such as aluminum or magnesium. Extinguishing these fires requires special dry powder extinguishing equipment, which may include powdered graphite or powder.

Class F: Fires that are high in cooking oil or fat in large catering establishments or restaurants.

Electrical fires: A fire in electrical equipment or circuitry does not create a fire extinguishing class on its own, as electricity is a source of fire that extinguishes fires or ignites them until they are isolated. 

But there are some pieces of equipment that can store deadly voltages inside capacitors even when isolated.

For such fire hazards, fire extinguishers designed specifically for the use of electricity such as carbon dioxide or dry powder should be used. 

Fire extinguishers are usually designed to deal with one or more classes of fire. There are designated fire extinguishers for this type of fire. 

Fire classification

Fire classification with material examples

Class A fires: Fire in carbonaceous materials such as wood, paper, etc.

Class B fires: Fires in flammable liquids such as gasoline. Oil Grease diesel etc.

Class C fires: Fire in flammable gases such as LPG, acetylene

Class D fires: Fire in flammable metals such as sodium, potassium and aluminum

Fire hazard assessment

Identify Hazards –

Risks include: Anything that can start a fire, such as bare flames, heaters or commercial processes such as cookers or hot air dryers

Anything that can burn in a fire, including waste piles, display materials, textiles or other flammable products Oxygen sources such as air conditioning, medical products or commercial oxygen supplies that can extinguish fires

Identify people at risk, including:

People who work near or with fire hazards.

People who work alone, or in isolated areas such as store rooms or Children with children or parents

Elderly people

disabled people

Diagnose vulnerable people (such as hospital-delivery room, ICU, etc.),

Reduce or reduce the risk:

Where possible, protect yourself from fire hazards - e.g.

Eliminate waste build-up and reduce Any threats you can't completely eliminate

Replace highly flammable substances with low flammable items.

Keep anything that can remove fire from flammable substances Employees Have a smoking policy for employees or customers who wish to smoke in a designated area near your premises (Smoking is prohibited at adjacent locations)

Once you have mitigated this risk in practice, you need to look at any risk that cannot be eliminated and decide what fire safety measures to take.

 

 

Fire spread or heat transfer

Four ways to heat transfer: It is through Convection, radiation, Conduction and direct contact

1.   Convection  

The hot air becomes less dense and rises into the cool new air to accelerate the fire with more oxygen.

In the case of extremely hot products of combustion and flame, heat is moved upwards sufficiently to ignite flammable substances.

This is especially important inside buildings or other structures where the shape of the fire can effectively form a fireplace.

2.   Conduction

It is the transmission of heat through the soil, which involves melting or destroying matter with great intensity and igniting flammable substances that come in contact or near a hot spot.

Metals such as copper, steel and aluminum are very efficient or good heat conductors. Other materials such as concrete, brickwork and insulation equipment are highly inefficient or poorly insulated. Poor conductors or good insulators are used in fire protection arrangements. When there is a faulty conductor Infinite It is ideal for fiber race protection.

Care must be taken to ensure that there are no other health risks associated with such materials.

Asbestos is a very poor heat conductor and is unbearable. Unfortunately, It has serious health problems that are now more than just fire protection materials and are banned in the UK, although it is still found in many buildings where it is widely used for fire protection. Was done

 

3.   Radiation

 

Often in a fire, the direct transmission of heat through the emission of heat waves from a surface is so rapid that the adjacent material is heated enough to ignite.

 

The shiny red surface of the metal surface will be a sign of the danger of intense radiation in a fire.

 

4.   Direct burning

 

It is the effect of a flammable substance that causes a fire to spread through direct contact, such as an open fire, in which a range of combustible fuels is easily spread in a bowl.

Categories: Classification of fire, Classification of fire extinguishers, Construction Safety, Fire Classes, HSE, Safety, Safety at Work place