Fire Extinguishers and Classes of Fires Greg Bennett

Fire Extinguishers and Classes of Fires Greg Bennett May 26, 2026 Last month we reviewed propane and grill safety. In that review, we mentioned dry chemical fire extinguishers. This month, we will review the classes of fires and fire extinguisher options. There are five (5) Classes of Fire. They are all represented by letters. Class A: ordinary combustibles, such as paper, household garbage, brush and leaves. These are the most basic fires and the easiest to extinguish. A Class A (water can) extinguisher will extinguish this type of fire, but if you only have a dry chemical unit, that will work. Class B: flammable liquids, such as gasoline. These are dangerous fires, and vapors are the issue, not the gasoline itself. A CO2 (carbon Dioxide) extinguisher is designed for Class B fires. A dry chemical unit will work as well, but not water. Gasoline has a specific gravity lower than water, and it will float on top of water and will not be extinguished. Class C: electrical fires A toaster or similar battery powered appliance etc. It needs to be noted that if the appliance or equipment is not plugged in, it is a Class A fire. If it is plugged in, it becomes Class C. For these fires, use a Dry Chemical extinguisher. Dry chemicals are referred to as ABC extinguishers, because they can extinguish all three (3) of these classification of fires. Class D: flammable metal fires, such as magnesium. These fires can be found primarily in cars. This requires a special type of extinguisher, a Class D extinguisher. These units are rare to find and very expensive. In the absence of such a unit, copious amounts of water can be used. These are the rarest fires of the five. Class K: kitchen/grease fires. This is the newest class of fire, specifically dealing with grease fires. They can be controlled with a Class K extinguisher, we call this “wet water”. There is an additive which will assist in controlling and suppressing grease fires. We hope this gives you a better understanding of the various types of fires, and how to extinguish each type. For most people, the best extinguisher choice is a Dry Chemical ABC), which is the most versatile unit. It will have a gauge, and so long as the needle is in the green it is OK. Once the unit is in the red, it can be discarded. It is cheaper to replace these units than it is to refill them. If you, your business, organization or HOA would like further information on this or any other fire department related topic, please contact our Community Outreach staff at: [email protected] or [email protected].