Smoke Detectors

Installing and Testing your Smoke Alarms

2. Keep your smoke alarms working properly

Because fire can grow and spread so quickly, having working smoke alarms in your home can mean the difference between life and death. Once the alarm sounds, you may have as few as two minutes to escape. Smoke alarms are the most effective early warning devices available. Just having a smoke alarm in your home cuts your chance of dying in a fire nearly in half.

You can reduce your risk even more by learning how to effectively use the smoke alarm's early warning to get out safely. Automatic home fire sprinklers reduce your risk of dying in a home fire even more.

Install your smoke alarms correctly:

Install smoke alarms on every level of your home, including the basement. Make sure there is an alarm in or near every sleeping area.
Mount the smoke alarms high on walls or ceilings—remember, smoke rises. Ceiling-mounted alarms should be installed at least four inches away from the nearest wall; wall-mounted alarms should be installed four to 12 inches away from the ceiling.
If you have ceilings that are pitched, install the alarm near the ceiling's highest point.
Don't install smoke alarms near windows, doors, or ducts where drafts might interfere with their operation.
Hard-wired smoke alarms operate on your household electrical current. They can be interconnected so that every alarm sounds regardless of the fire's location. This is an advantage in early warning, because it gives occupants extra time to escape if they are in one part of the home and a fire breaks out in another part.
Alarms that are hardwired should have battery backups in case of a power outage, and should be installed by a qualified electrician.
Don't paint your smoke alarms; paint, stickers or other decorations could keep them from working properly.

Install all new smoke alarms and batteries when you move into a new home, unless the seller/renter can certify that they are new.

Test your smoke alarms when you return from an extended trip to make sure your batteries haven't gone dead while you were away.

Keep your smoke alarms working properly:

Test your smoke alarms at least once a month, following the manufacturer's instructions.
Replace the batteries in your smoke alarm once a year, or as soon as the alarm "chirps," warning that the battery is low. HINT: schedule battery replacements for the same day you change your clock from daylight to standard time in the fall.
Never "borrow" a battery from a smoke alarm. Smoke alarms can't warn you of fire if their batteries are missing or have been disconnected.
Don't disable smoke alarms even temporarily – you may forget to replace the battery. If your smoke alarm is sounding "nuisance alarms," it may need dusting or vacuuming. If that doesn't work, try relocating it further away from kitchens and bathrooms, where cooking fumes and steam can cause the alarm to sound.
Regularly vacuuming or dusting your smoke alarms following manufacturer's instructions can help keep it working properly.
Smoke alarms don't last forever. Replace your smoke alarms once every 10 years.
Make sure that everyone in your home can identify and awaken to the sound of the alarm.
Plan regular fire drills (twice a year is best) to ensure that everyone knows exactly what to do when the smoke alarm sounds. Hold a drill at night to make sure that sleeping family members awaken at the sound of the alarm.
If you are building a new home or remodeling your existing home, consider installing an automatic home fire sprinkler system. Sprinklers and smoke alarms together cut your risk of dying in a home fire 82 percent relative to having neither – a savings of thousands of lives a year.
Read NFPA's smoke alarm fact sheet

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