Dry chemical extinguishers can be used on all fire except oil fires (class F fires)
Foam extinguishers are best used on combustible materials (class A) and flammable solids and liquids (class B)
Water extinguishers can only be used on combustible materials such as wood, paper, cloth, trash, and plastics (class A)
Wet chemical extinguishers can be used on combustible materials (class A) and oil fires (class F). These extinguishers have been specifically developed to tackle fires involving cooking oils and fats and contain potassium salts which both cool the flames and smother the fire’s oxygen content.
CO2 extinguishers can be used on flammable liquids (class B) and electrical fires.
Fire extinguishers with a Class C rating are suitable for fires in “live” electrical equipment. Both monoammonium phosphate and sodium bicarbonate are commonly used to fight this type of fire because of their nonconductive properties.
