An extinguisher’s letter ratings tell the types of fire it can put out: Class A (combustible solids such as wood, paper, fabrics, or trash), B (grease and other flammable liquids), or C (electrical). The number preceding the A or B rating (for example, 1-A or 5-B) indicates the size of a standard test fire that the extinguisher can put out; the higher the number, the greater the extinguisher’s firefighting capacity. The C rating means that the extinguishing materials do not conduct electricity; it has no number.
Match extinguishers to potential fire hazards, or buy multipurpose ABC extinguishers rated at least 2-A 10-B:C. Check the canister for the Underwriters’ Laboratories (UL) or Factory Mutual (FM) label and for clear operating instructions. Disposable or gaugeless extinguishers are unreliable; replace them. Do not use water on Class B or C fires.
Install extinguishers in the kitchen and in or near the living room, bedrooms, basement, and garage. They should be in plain view, away from but convenient to fire hazards. Make sure the entire family knows where they are and how to use them. Inspect the pressure gauge periodically. If pressure drops or if the extinguisher is used, even briefly, have it recharged by an extinguisher service company.