What is a fire extinguisher?
Updated August 2026
A fire extinguisher is a pressurized cylinder that discharges a chemical agent onto a fire, sized to knock down a blaze no bigger than a wastebasket. The letters on the label say which fires it is rated for: A covers wood, paper, and cloth, B covers flammable liquids such as gasoline and paint thinner, C covers energized electrical equipment, and K covers hot cooking grease. A household unit should read ABC, the multipurpose dry chemical that handles all three ordinary house fires. The numbers in a rating like 2-A:10-B:C describe capacity, not size: higher means more fire knocked down.
Where it is
Plan on one ABC unit per floor, plus dedicated units in the kitchen and the garage or workshop. Mount each one on its bracket 3 to 5 feet off the floor, in plain sight, near the room exit rather than deep inside the room, so you are never reaching across flames to grab it. The kitchen extinguisher belongs by the doorway, not beside the range. A 2.5-pound unit suits a kitchen or a bedroom hallway; buy a 5-pound or 10-pound unit for the garage, where gasoline, batteries, and sawdust live. Check the pantry and the coat closet before you buy more: most homes already own one, buried behind something.
What it does
An extinguisher buys you the first minute. Use the PASS sequence: Pull the pin, Aim at the base of the flames, Squeeze the handle, Sweep side to side from 6 to 8 feet back. That is all the time you get, because a 2.5-pound home unit empties in roughly 8 to 12 seconds. A fire in an ordinary room can double in size about every 30 seconds, so if the flames are not out after the first burst, drop the cylinder, get everyone outside, and call 911 from the yard. A failed extinguisher looks obvious once you know the signs: a needle sitting outside the green band, a missing pin or broken tamper seal, rust or a dent in the cylinder, a cracked hose, or powder packed into a solid cake at the bottom.
Maintenance
Glance at the gauge every month and turn the cylinder upside down twice a year, giving the base a few taps to break up settled powder. The monthly inspection routine takes under a minute per unit, and the full checklist covers the annual once-over. Disposable units get replaced at 10 to 12 years from the date stamped on the label or the bottom rim. Rechargeable units need professional service every 6 years and a hydrostatic test at 12 years, plus a recharge after any discharge at all: even a one-second test burst lets the pressure bleed off over the following weeks. Service life varies by type, so read the label before you assume yours is fine.
What it costs to replace
A replacement fire extinguisher runs $20–60 for a household ABC unit, or $20–45 to have a rechargeable one refilled.
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Frequently asked questions
Can I use a fire extinguisher on a grease fire?
You can, but it is the second choice. For a pan fire, kill the burner and slide a metal lid or a cookie sheet over the pan to starve it of air. An ABC dry chemical unit will put out a small stovetop fire, though the blast can splash burning oil if you aim straight down into the pan, so sweep from the near edge instead. Never throw water on grease, and never carry a flaming pan to the sink. Commercial kitchens use Class K wet chemical units for exactly this reason.
How do I tell if my fire extinguisher still works?
Four checks. The gauge needle must sit inside the green band; red on either side means overcharged or discharged. The pull pin must be present with the plastic tamper seal unbroken. The cylinder must be free of rust, dents, and corrosion at the base, and the hose or nozzle must be clear of insects and debris. Finally, find the manufacture date stamped on the bottom or printed on the label and count forward 10 to 12 years for a disposable unit.
How do I get rid of an old fire extinguisher?
Do not put a pressurized cylinder in the trash or the recycling bin. If the unit is empty, squeeze the lever outdoors to confirm zero pressure, remove the head, and the steel body can usually go into scrap metal. If any charge remains, take it to a household hazardous waste drop-off or a fire equipment servicing shop. Many fire departments accept old units at the front desk, and some run collection days: call the non-emergency line first and ask.