Each year, fire kills or severely injures thousands of people and destroys millions of dollars worth of property. Many fires start small, and may be extinguished or controlled by a fire extinguisher. You can minimize property damage by having the right type of fire extinguisher and knowing how to use it.
Fires are classified by the types of materials involved in the fire. Most fires fit into one or a combination of Four classifications: Class A, Class B, Class C and Class D. The chart in Figure 1 will help you classify the fires that you might encounter in your home or business. It gives general recommendations for the types of extinguishers most likely to be used to extinguish these fires.

Fire extinguishers are identified by the class, extinguishing agent, and size of a fire that they are designed to extinguish. Universal fire class symbols are present on fire extinguisher labels. These labels tell you which classes of fires the unit will safely extinguish.
Extinguisher size is shown on the label in either pounds of dry chemical or gallons of liquid contained in the unit. (The size is sometimes identified in the manufacturer's model number.) More dry chemical, for example, will not necessarily mean that a unit will extinguish more fire than one with less chemical. This is due to variations in chemicals used in extinguishers. Look for the classification or rating to be certain of the unit's extinguishing capacity.
The classification, or rating, shows the size of a Class A or B fire the unit can be expected to put out. Controlled laboratory testing (by Underwriters' Laboratories or Fire Marshall, UL or FM) determines classification before a manufacturer puts a model on the market. The higher the rating or classification, the greater the extinguishing capacity. For example, a unit classified 4A can be expected to extinguish twice as much Class A fire as one classified 2A. When comparing units of similar physical size, compare classifications to be sure which unit will provide the greatest fire fighting potential.
Remove the fire extinguisher from it's box and mount it in a readily accessible location. Read the operating instructions on the label and become familiar with the units operating components. Be sure to instruct all family members or employees in the use and location of a fire extinguisher. Prepare ahead of time! Do not wait until a fire occurs to read and interpret operating instructions. Although extinguishers may vary slightly in operating procedures, most will use the following steps:
Place the mounting bracket for the extinguisher on a firm surface 31/2 to 5 feet above the floor. Extinguishers should be installed away from any potential fire hazards and near exits or escape routes in the areas you plan to protect.
Inspect extinguishers at least once a month. Check that each is in its designated location and at the proper pressure. The tamper seal should not be broken and the unit should not have any readily apparent damage. Check the discharge hose for damage and the nozzle for obstructions. Most pressurized units sold today have a gauge that shows whether the unit has sufficient stored pressure to discharge the contents. If the pressure gauge shows insufficient pressure, the extinguisher should be recharged or replaced immediately. Extinguishers also should be recharged after each use regardless of the amount of chemical discharged. Most fire extinguisher can be serviced or repaired, check the Yellow Pages under fire extinguishers.
When shopping for a fire extinguisher always look for the UL or FM seal of approval. Know what size and type you want before you shop for a fire extinguisher. Be sure the unit you buy is matched for the Class (A, B, C, D, or K) you are trying to protect. The hardware on an extinguisher can be either plastic or metal. Some extinguishers of lesser price may not be rechargeable. If this is a concern, read the label and check with the dealer before making the purchase. Non-rechargeable units typically are less expensive than rechargeable types.
The most important aspect of fire safety is to have a plan of action when a
fire is discovered. This plan should cover the steps required to save lives and
property.
Be prepared for a fire, plan your course of action beforehand. Post an emergency escape plan, then practice it often. A portable fire extinguisher is only a first-aid or emergency unit. It can be used on small fires and only during the initial stage. The discharge time on most fire extinguishers is very short, it can be measured in only seconds! Regardless of your actions be sure you or somebody else notifies the Fire Department. Make sure you use the proper Class of fire extinguisher for the hazard you are trying to extinguish. Do not risk your life or the lives of others in fighting a fire that has grown too large for the extinguisher to put out. Always be sure you have a clear escape path, don't get trapped fighting a fire! If you are unsure how to operate a fire extinguisher, get out. Saving your life and others comes first! Be proactive, use fire prevention measures in the home and at work everyday.