FIRE DEPARTMENT
FIRE EXTINGUISHERS
Always read the owner's manual after purchasing a fire extinguisher! Improper use can result in serious bodily injury or property damage.
Types of fires
There are four types of fires which are classified as:
- Class A fires of ordinary combustibles or fibrous materials, such as wood, paper, cloth, rubber and some plastics.
- Class B fire of flammable or combustible liquids such as gasoline, kerosene, paint, paint thinners and propane.
- Class C fires of energized electrical equipment, such as appliances, switches, panel boxes and power tools.
TYPES OF FIRE EXTINGUISHERS
Fire extinguishers are classified by the size and class of the fire they are designed to extinguish, and by their extinguishing agent. 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. Some extinguishers are able to put out more than one class of fire and are marked with multiple ratings such as AB, BC and ABC.
Class A and B extinguishers carry numerical ratings to indicate how large a fire can safely be put out with that extinguisher.
Class C extinguishers only have a letter rating to indicate that the extinguishing agent will not conduct electrical current. Class C extinguishers automatically also carry a Class A or B rating.
- ABC-rated multipurpose dry powder extinguishers are almost always red in color and have either a long narrow hose or just a short nozzle. These extinguishers are very light (5-25 lbs. total weight).
- Water extinguishers are usually silver in color, have a flat bottom, a long narrow hose and are quite large (21/2 gallon capacity).
- Foam extinguishers have a similar appearance to water extinguishers and those without gauges have a handle inset in the flat bottom (turn the extinguisher upside down to start and use it).
- CO2 (carbon dioxide) extinguishers are generally red, have a large tapered nozzle, and are very heavy (15-85 lbs.) Do not drop a CO2 cylinder - it is a high-pressure cylinder (from 1500 to 2150 lbs) and could do a great deal of damage. CO2 cylinders do not have pressure gauges and therefore must be weighed to determine the amount of contents.
Check the pressure gage on the fire extinguisher monthly - it must be in the green area (100 to 175 lb pressure) to work properly. Also, in dry chemical extinguishers the powder has a tendency to settle. Shake the extinguisher periodically to aid its performance.
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