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Smart Home

How to stop smoke detectors that keep going off

Because sometimes there really is smoke without fire.

Chris Monroe/CNET

Nothing can set your teeth on edge like a smoke alarm going off when there's no emergency. You may be tempted to remove the batteries, but that could leave your home vulnerable to a real fire. 

Here's why your smoke detector goes off and how you can deal with the false alarms.

How smoke detectors work

There are two different types of smoke detectors. Ionization smoke detectors have two plates with an electric charge flowing between them. When something -- like smoke -- flows between these two plates, the electric charge is interrupted and the alarm is triggered. 

Photoelectric smoke detectors have a small light inside. When something enters the detector and reflects the light onto a sensor, the alarm is triggered. 

Notice how both of these types of detectors don't really detect smoke. They're triggered by foreign objects interacting with parts inside the detectors. This means that anything that can float into your smoke detector, like vapor, steam, smoke and large puffs of dust, can trigger your smoke detector. 

This is why it may go off when your cooking, even if you're not burning anything. The steam coming off of the food is triggering the alarm. Hair spray and other aerosols sprayed near the detector can set it off, too.

How to cope 

The most obvious way to cope with annoying smoke detectors is to take them down. But that leaves you vulnerable if there is a real fire and isn't safe at all. Don't do it.

Instead, install your smoke alarms in strategic places, ventilate the area and replace old alarms.

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Place your smoke alarms carefully throughout your home. Photoelectric smoke alarms are best near bathrooms and kitchens where there's a lot of steam because humidity doesn't affect them as much. Note that the National Fire Protection Association recommends placing detectors 10 feet (3 meters) from your stove to help prevent false alarms while cooking.

Next, be sure to use your kitchen's exhaust fan when cooking. If you let the smoke and humidity out through the fan's duct, it'll be less likely to set off your smoke alarm. Be sure to also use your exhaust fan or crack a window in the bathroom to prevent humidity or aerosols from wafting out to the alarm.

If you don't have smart smoke detectors, you may want to consider installing them. Some smart detectors include Nest ProtectHalo Smart LabsFirst Alert and Roost.  

You can quickly shut off these detectors using an app on your phone if there's a false alarm. Smoke detectors are far less aggravating when you don't need to climb on a chair to shut them off.

Read next: Here are our buying guide to help you pick the right smart smoke detector for your home.

Read more: These four projects for beginners will get your home smart in no time.