This self-paced online course covers workplace fire extinguishers, including the A, B, C and D types of fire extinguishing agents.

Upon completion you should be able to:

• Understand the different classes of fires
• List and understand the different types of extinguishing agents
• Operate all basic types of extinguishers and the technique for safe use

Who Will Benefit

Anyone whose job involves designing, reviewing, evaluating or installing fire protection systems, including: designers, installers, engineers, electrical contractors, technicians, project managers, fire marshals, and architects.

Course Summary

• Used properly, portable fire extinguishers can be effective fire fighting tools in the early stages of a fire. However, if you discover a fire, the first thing you must do is sound the alarm. Do not attempt to do anything else until you’re sure the fire department is being notified and people are evacuating the building.
• For firefighting purposes, fires are divided into different classes; these will present different hazards, and require different types of extinguishers:
  • Class A - ordinary combustibles
  • Class B - flammable and combustible liquids; flammable gases
  • Class C - fires involving energized electrical equipment
  • Class D - combustible metals
  • Class K - combustible cooking oil or fat
• Fire extinguishers contain extinguishing agents, the material that actually does the work in putting out the fire. These agents may be in the form of a liquid, gas, gas/mist, foam or dry chemical. They put out the fire in different ways.
• Water is a very effective extinguishing agent for fires in ordinary combustibles (Class A). It works by cooling the fire.
• Dry chemical extinguishers are very popular, and multipurpose: they are rated either Class B, C, or Class A,B,C. They work by interrupting the chemical chain reaction of the fire.
• Foam extinguishers are also multipurpose, rated Class A, B; they work by smothering the fire. Note that because they are water-based, foam extinguishers are not rated for fires in energized electrical equipment (Class C).
• Carbon dioxide is a multipurpose extinguishing gas, rated Class B,C. It works by displacing air, depriving the fire of oxygen.
• Halogenated agents, rated Class B, C, also work by interrupting the chemical chain reaction. Unlike dry chemical extinguishers, they do not leave a corrosive residue, and so are preferred in areas containing delicate electronic equipment.
• Dry powder agents are rated Class D. They smother the fire.