Fire Extinguisher Safety Tips


a-exting Class A:
Wood, paper and other combustible solids.
b-exting Class B:
Flammable liquids such as gasoline, oil, and oil-based paint.
c-exting Class C:
d-exting Class D:
Certain combustible metals, such as magnesium, titanium, potassium and sodium. These metals burn at high temperatures and give off sufficient oxygen to support combustion. They may react violently with water or other chemicals, and must be handled with care.


All ratings are shown on the extinguisher faceplate. Some extinguishers are marked with multiple ratings such as AB, BC and ABC. These extinguishers are capable of putting out more than one class of fire.

Class A and B extinguishers carry a numerical rating that indicates how large a fire an experienced person can safely put out with that extinguisher.

Class C extinguishers have only a letter rating to indicate that the extinguishing agent will not conduct electrical current. Class C extinguishers must also carry a Class A or B rating.

Class D extinguishers carry only a letter rating indicating their effectiveness on certain amounts of specific metals.


  • Know the locations of the fire extinguishers in your work area.
  • Make sure the class of the extinguisher is safe to use on fires likely to occur in the immediate area.
  • Check the plastic seal holding the pin in the extinguisher handle. Has the extinguisher been tampered with or used before? Report any broken/missing seals/pins.
  • Look at the gauge and feel the weight. Is the extinguisher full? Does it need to be recharged?
    • Water, some foam, and dry chemical extinguishers have gauges indicating the pressure inside the extinguisher. The pressure needle should be in the "green" area (generally 100-175 lbs., depending on the type of agent).
    • CO2 (carbon dioxide) extinguishers are high-pressure cylinders with pressures ranging from 1500 lbs to 2150 lbs. These extinguishers DO NOT have gauges and must be weighed by Fire Safety Unit staff to determine the amount of contents remaining.
    • Make sure the pin, nozzle and nameplate are intact.
    • Be aware of the condition of your area's extinguishers by visual inspection on a monthly basis to ensure you have a working extinguisher there when you need one.
    • Report any missing, empty or damaged fire extinguishers whenever you notice any discrepancies.

Fire Extinguisher Use

Keep your back to an unobstructed exit and stand 6 to 8 feet away from the fire. Follow this 4-step procedure.

Remember the PASS word

Pull the pin. This unlocks the operating lever and allows you to discharge the extinguisher. Some extinguishers may have a different release device.

Aim low: Point the extinguisher at the base of the fire with the nozzle or hose.

Squeeze the lever above the handle: This will discharge the extinguisher's contents. To stop the discharge, release the lever. Some extinguishers may have a button instead of a lever.

Sweep from side to side: Aim and keep the extinguisher at the base of the fire and sweep back and forth until the flames appear to be out.  Repeat the process if the fire reignites.