Identify the type of materials in the area

Class A: 

SOLIDS such as paper, wood, plastic etc

Class B: 

FLAMMABLE LIQUIDS such as paraffin, petrol, oil etc

Class C:  

FLAMMABLE GASES such as propane, butane, methane etc

Class D:

METALS such as aluminum, magnesium, titanium etc

Class E:

Fires involving ELECTRICAL APPARATUS

Class F:

Cooking OIL & FAT etc

 

Types of Fire Extinguishers

Water and Foam

Water and Foam fire extinguishers extinguish the fire by taking away the heat element of the fire triangle. Foam agents also separate the oxygen element from the other elements.

Water extinguishers are for Class A fires only - they should not be used on Class B or C fires. The discharge stream could spread the flammable liquid in a Class B fire or could create a shock hazard on a Class C fire.

Wet Chemical

Wet Chemical is a new agent that extinguishes the fire by removing the heat of the fire triangle and prevents re-ignition by creating a barrier between the oxygen and fuelelements.

Wet chemical of Class K extinguishers were developed for modern, high efficiency deep fat fryers in commercial cooking operations. Some may also be used on Class A fires in commercial kitchens.

Clean Agent

Halogenated or Clean Agent extinguishers include the halon agents as well as the newer and less ozone depleting halocarbon agents. They extinguish the fire by interrupting the chemical reaction of the fire triangle.

Clean agent extinguishers are primarily for Class B & C fires. Some larger clean agent extinguishers can be used on Class A, B, and C fires.

Dry Powder

Dry Powder extinguishers are similar to dry chemical except that they extinguish the fire by separating the fuel from the oxygen element or by removing the heat element of the fire triangle.

However, dry powder extinguishers are for Class D or combustible metal fires, only. They are ineffective on all other classes of fires.

Water Mist

Water Mist extinguishers are a recent development that extinguish the fire by taking away the heat element of the fire triangle. They are an alternative to the clean agent extinguishers where contamination is a concern.

Water mist extinguishers are primarily for Class A fires, although they are safe for use on Class C fires as well.

Cartridge Operated Dry Chemical

Cartridge Operated Dry Chemical fire extinguishers extinguish the fire primarily by interrupting the chemical reaction of the fire triangle.

Like the stored pressure dry chemical extinguishers, the multipurpose dry chemical is effective on Class A, B, and C fires. This agent also works by creating a barrier between the oxygen element and the fuel element on Class A fires.

Ordinary dry chemical is for Class B & C fires only. It is important to use the correct extinguisher for the type of fuel! Using the incorrect agent can allow the fire to re-ignite after apparently being extinguished successfully.

Fire Extinguisher Use

It is important to know the locations and the types of extinguishers in your workplace prior to actually using one.

Fire extinguishers can be heavy, so it's a good idea to practice picking up and holding an extinguisher to get an idea of the weight and feel.

Take time to read the operating instructions and warnings found on the fire extinguisher label. Not all fire extinguishers look alike.

Practice releasing the discharge hose or horn and aiming it at the base of an imagined fire. Do not pull the pin or squeeze the lever. This will break the extinguisher seal and cause it to lose pressure.

When it is time to use the extinguisher on a fire, just remember PASS!

Pull the pin.

Aim the nozzle or hose at the base of the fire from the recommended safe distance.

Squeeze the operating lever to discharge the fire extinguishing agent.

Starting at the recommended distance, Sweep the nozzle or hose from side to side until the fire is out. Move forward or around the fire area as the fire diminishes. Watch the area in case of re-ignition.

Watch our video on “How to use a Fire Extinguisher” for more information and a visual demonstration.

Fire Extinguisher Inspection

Like any mechanical device, fire extinguishers must be maintained on a regular basis to ensure their proper operation. You, the owner or occupant of the property where the fire extinguishers are located, are responsible for arranging your fire extinguishers' maintenance.

Fire extinguishers must be inspected or given a "quick check" every 30 days. For most extinguishers, this is a job that you can easily do by locating the extinguishers in your workplace and answering the three questions below.

  • Is the extinguisher in the correct location?
  • Is it visible and accessible?
  • Does the gauge or pressure indicator show the correct pressure?