Selecting the Proper Extinguisher Each year, fire kills or severely injures thousands of people and destroys millions of dollars worth of property. Many fires begin small and may be extinguished, or controlled until help arrives, by a fire extinguisher. You can minimize personal and property damage by having a fire extinguisher on hand and knowing how and when to use it.
Fires are classified by the types of materials involved in the fire and the location of the fire. Most fires fit into one or a combination of three classifications: Class A, Class B or Class C. The chart in Figure 1 will help you classify the fires that you might encounter in your home or on your farm. 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 and size of a fire that they are designed to extinguish and by the extinguishing agent they contain. The universal fire class symbols are present on extinguisher labels. They tell you which classes of fires the unit will extinguish safely.
The size of the extinguisher 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.
Read the operating instructions on the label and examine the unit when
it is purchased. Be certain to instruct all family members and
employees on the premises 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. This includes checking to be sure that each is in its recommended location, the pressure is up, the tamper seal is not broken, no damage has been done to the unit, and the hose or nozzle is unobstructed. Most units sold today are pressurized and have a gauge that shows whether the unit has sufficient stored pressure to discharge the contents. If, after a routine inspection, the pressure gauge shows insufficient pressure, the extinguisher should be recharged or replaced immediately. Extinguishers also should be recharged after each use, despite the amount of chemical discharged. If in doubt about where you can get an extinguisher serviced or repaired, check the Yellow Pages under fire extinguishers.
Remember to look for the UL or FM seal of approval. Be aware of the recommended size and type you want before you shop for a fire extinguisher. Be certain you are purchasing a unit that will give you maximum protection. The hardware on an extinguisher can be either plastic or metal. Both types, if approved by a recognized testing laboratory, should serve for their intended purpose.
Some extinguishers of lesser price may not be rechargeable. Read the label and check with the dealer before purchase to see if the unit you are considering can be recharged after use. Although some non-rechargeable units may be greatly reduced in price, it is usually economical to purchase a unit that can be recharged, rather than buying an entirely new unit every time you use your extinguisher.
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.
A portable fire extinguisher is only a first-aid or emergency unit. It can be used on small fires only in the initial stages. Do not expect miracles from a fire extinguisher. The discharge time on most units is only seconds! Do not risk your life or the lives of others in fighting a fire that has grown too big for the extinguisher. Saving lives comes first! Practice fire prevention measures in the home and on the farm to be safe. Hopefully you will never need an extinguisher.
| Size Range (lbs.) | Location |
|---|---|
| HOME | |
| First Unit, 2 1/2-5 | Kitchen near exit door |
| Second Unit, 2 1/2-5 | Basement near exit door |
| Third Unit, 2 1/2-5 | Near wood stove |
| FARM SHOP | |
| One Unit, 5-10 | Near exit door |
| COMBINE | |
| First Unit, 5-10 | Near cab door |
| Second Unit, 5-10 | On opposite side of cab at ground level |
| BALER | |
| One Unit, 2 1/2-5 | On structural member |
| CAR OR TRUCK | |
| One Unit, 2 1/2-5 | Accessible to driver |
| BARN OR OUTBUILDINGS | |
| One Unit, 5-10 | In accessible location |
Figure 1. Recommended sizes and locations of fire extinguishers. (The multipurpose, ABC dry chemical extinguisher is cited in all examples because it can serve as protection for all expected fires in all locations listed.)
Acknowledgments to Michelle L. Wallingford for her contributions to this publication.
Reviewed by Drs. Mike Lichtensteiger and Robert Gustafson, Dept. Of Agricultural Engineering, and Dr. Judy Wessel, Dept. of Family Resource Management. Funded in whole or in part from Grant Number U05/CCU506070-03, "Cooperative Agreement Program for Agricultural Health Promotion Systems," National Institute for Occupational Safety and Health.
All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status.
Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.
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