Learn about smoke alarms

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Why should I have a working smoke alarm?

A properly installed and maintained smoke alarm is the first thing in your home that can alert you and your family to a fire 24 hours a day, seven days a week. Home fire sprinklers can also alert you, but are a few seconds slower than smoke alarms. Whether you're awake or asleep, a working smoke alarm is constantly on alert, scanning the air for fire and smoke.

According to the National Fire Protection Association, almost two-thirds of home fire deaths resulted from fires in properties without working smoke alarms. A working smoke alarm significantly increases your chances of surviving a deadly home fire.

What types of smoke alarms can I buy?

There are many brands of smoke alarms on the market, but they fall under two basic types: ionization and photoelectric.

Ionization and photoelectric smoke alarms detecting different types of fires. Since no one can predict what type of fire might start in their home, the USFA recommends that every home and place where people sleep have:

There are also alarms for people with hearing loss. These alarms may strobe lights that flash and/or vibrate to alert those who are unable to hear standard smoke alarms when they sound.

What powers a smoke alarm?

Smoke alarms are powered by battery or by your home's electrical system. If the smoke alarm is powered by battery, it runs on either a disposable 9-volt battery or a non-replaceable 10-year lithium (“long-life”) battery. Alarms that get power from your home's electrical system, or “hardwired,” usually have a back-up battery that will need to be replaced once a year.

Are smoke alarms expensive?

Smoke alarms are not expensive and are worth the lives they can help save.

Alarm type Cost
Ionization and photoelectric $6 and up
Dual sensor $24 and up
Smoke alarms with a microprocessor
(faster to alert, fewer false alarms)
$30 and up
Radio frequency/wireless
(communicate from one to the next without wires)
$40 and up

Your city, county or state may require a specific type of alarm. Please check with your local fire marshal for information on what type of alarm you need.

Some fire departments offer reduced-price, or even free, smoke alarms. Contact your local fire department's non-emergency phone number for more information.

Where do I put smoke alarms in my home?

Some fire departments will install battery-operated smoke alarms in your home at no cost. Contact your local fire department’s non-emergency phone number for more information.

How do I take care of my smoke alarm?

Is your smoke alarm still working? A smoke alarm with a dead or missing battery is the same as having no smoke alarm at all.

A smoke alarm only works when it is properly installed and regularly maintained. Maintain your smoke alarms according to the manufacturer’s instructions. Below are some general maintenance tips.

Smoke alarm powered by a 9-volt battery

Smoke alarm powered by a 10-year lithium (or “long-life”) battery

Smoke alarm that is hardwired into your home's electrical system

What do I do if my smoke alarm sounds while I'm cooking?

Never disable a smoke alarm while cooking! If a smoke alarm sounds while you're cooking or taking a shower with lots of steam, do not remove the battery. You should:

Disabling a smoke alarm or removing the battery can be a deadly mistake.

Additional smoke alarm resources