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 equipment
CLASS F: Cooking OIL & FAT etc
The water extinguisher is the cheapest and most used fire extinguisher. This is used for Class A fires. It is not suitable for use for Class B (Liquid) fires, or fires involving electricity.
The foam extinguisher is more versatile but more expensive than the water extinguisher. This is used for Classes A & B fires. The foam extinguisher is not recommended for fires involving electricity but is safer than water if inadvertently sprayed onto live electrical equipment.
The dry powder extinguisher can be used on Classes A, B & C fires. This extinguisher is best for Class B (liquid) fires and also Class C (Gas) fires but ensure that the gas supply has been isolated first. Also available are special powders for Class D (Metal) fires. When these are being used indoors the powder can damage machinery and also obscure vision.
Carbon Dioxide is ideal for fires involving electrical equipment, and can also be used to extinguish Class B (Liquid) fires, but has no post-fire security and the fire could re-ignite.
Specialist extinguisher for Class F fires.
A specialist fire extinguisher for use on Class D fires- metal fires such as lithium, Sodium, Aluminium, and Manganese when in the form of swart or turnings.