What you need to know about smoke detectors
Last updated: January 1
Smoke detectors are a vital first line of defense for you and your family. But, these devices need to be both installed and maintained correctly in order to provide you with adequate protection. In one quarter of the U.S. home fires in which smoke detectors failed, dead batteries were the cause, according to the National Fire Protection Association (NFPA).
By properly selecting, positioning and maintaining the smoke alarms in your house, you can have peace of mind that you're taking an important step to help protect your family in case of a fire.
Features of smoke detectors
hile different smoke detectors may look similar, there are important features that vary among models. First, how is it powered? Some alarms are powered by a battery, whereas others are hardwired into your house's electrical system (and are typically equipped with a backup battery), the U.S. Fire Administration says.
All of the smoke alarms throughout your house should be interconnected through hardwiring or a wireless signal, suggests Richard Roux, senior electrical specialist with the National Fire Protection Association (NFPA). "That means when one alarm sounds, they all do," Roux says. New homes are required to include hardwired, interconnected smoke alarms with backup batteries, the American Red Cross says. If you don't already have the wiring in your home, you can buy devices that interconnect wirelessly, but you may need to buy models from the same brand in order to ensure they can communicate, Consumer Reports says.
Remember, some models include a built-in carbon monoxide (CO) detector, which alerts you to dangerous levels of this deadly gas, Consumer Reports says. If your smoke alarm isn't a dual model with a CO detector built in, you'll want to also purchase a CO alarm and install it in your home. CO alarms should be installed outside all sleeping areas and on every level of the home, the Consumer Product Safety Commission says.
Also, what type of sensor does the smoke alarm use: ionization or photoelectric? While one type is better at detecting flaming fires, the other is better at detecting smoldering fires. "If a fire smolders with no flame, then a photoelectric sensor will detect it first," Roux says. "If it is a hot, flaming fire, then an ionization sensor will likely sound first." Many smoke alarm models are now dual-sensor, meaning they use both technologies. If you don't have dual-sensor alarms, the NFPA recommends installing both ionization and photoelectric alarms in your home.
The NFPA recommends placing a smoke alarm inside every bedroom, outside every sleeping area and on every level of your home, including the basement. Place the alarms high on the wall, the NFPA advises, so there are no more than 12 inches from the top of the alarm to the ceiling. To avoid false alarms, position units more than 10 feet from cooking appliances and 3 feet from bathrooms with a shower or tub (steam can accidentally trigger the alarms). There are special guidelines for a pitched roof and high ceilings, so check with your local building or fire department, the smoke alarm manufacturer or the NFPA for assistance.
How to maintain and when to replace
Like coupons and canned goods, smoke alarms have an expiration date. "They have a life of 10 years," Roux says. "But, if it has a built-in CO detector, you'll need to replace it sooner." According to Consumer Reports, most CO detectors come with a five- to seven-year warranty.
If you have a battery-powered smoke alarm, it may start chirping to alert you that the battery is running low. Be sure to replace the batteries right away if you hear the chirping. Do not unplug it to mute the sound. According to the NFPA, among fires in which smoke alarms were present but didn't operate, 46 percent of the alarms had missing or disconnected batteries.
Keep ahead of the chirp and any other problems by testing your smoke alarms monthly, the U.S. Fire Administration recommends. Simply use your finger or a broom handle to press the "test" button to ensure the alarm sounds. "I can't stress the importance of testing enough," Roux says. "It's the only way you can know that your smoke alarm is working." When it comes to the safety of you and your family, that's one test well worth planning for.
In addition to testing your alarms monthly, you'll want to maintain a regular replacement schedule. If your alarm has "long life," or nonreplaceable batteries, they can be effective up to 10 years without any battery replacement needed, the NFPA notes. But if you have any other type of batteries in your alarm, replace them at least once a year.
By understanding how to place, maintain and test your smoke alarms, you can help protect your family in case of fire.