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BRK 9120B Review

Editor’s Note: This product has been removed from our side-by-side comparison because it has been replaced by another product. You can still read our original review below, but Top Ten Reviews is no longer updating this product’s information.

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BRK 9120B image: A 9-volt battery backup ensures that this smoke alarm will function during a power outage.

BRK 9120B image: A 9-volt battery backup ensures that this smoke alarm will function during a power outage.
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BRK 9120B image: When there are multiple alarms in a home, the latching alarm indicator on this model is useful for showing which alarm sounded first.

BRK 9120B image: When there are multiple alarms in a home, the latching alarm indicator on this model is useful for showing which alarm sounded first.
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BRK 9120B image: The 10-year warranty on this alarm will give you peace of mind when planning for emergencies in the home.

BRK 9120B image: The 10-year warranty on this alarm will give you peace of mind when planning for emergencies in the home.
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BRK 9120B image: This smoke detector has smart technology to minimize nuisance alarms, and you can use it throughout the home.

BRK 9120B image: This smoke detector has smart technology to minimize nuisance alarms, and you can use it throughout the home.

Editor’s Note: This product has been removed from our side-by-side comparison because it has been replaced by another product. You can still read our original review below, but Top Ten Reviews is no longer updating this product’s information.

The white BRK 9120B is a hard-wired smoke detector powered by your home's electrical system. It measures 5.6 inches in diameter and 2 inches high. A 9-volt battery backup ensures your alarm will still function during a power outage. The battery compartment is located on the side of the smoke detector, so you can replace the batteries without taking down the alarm.

This smoke detector uses dual-chamber ionization smoke sensors to detect a fire. Ionization smoke sensors are best at detecting the small particles produced by flaming fires, such as those started by paper or kitchen grease. The alarm comes with a 10-year limited warranty. You should replace your smoke detectors after 10 years, so the warranty provides coverage for the lifetime of your alarm.

Red or green LEDs show the state of this electric smoke detector. In the alarm's normal mode, when running on AC power, the green LED remains on. When the alarm is running on the battery backup, the green LED is off and a red LED flashes once per minute. If the battery is low or missing, the red LED will flash and there will be a chirping sound once per minute.

If the alarm does go off, a red LED flashes repeatedly. You'll also hear a pattern of three beeps, pause, three beeps, pause. The BRK 9120B has smart technology to reduce the number of nuisance alarms. If the alarm does go off and there's no fire, a single test/silence button provides a quick way to silence the alarm for up to 10 minutes.

A latching alarm indicator automatically activates after the alarm is exposed to an alarm level of smoke. This indicator helps you, emergency responders or service technicians identify which alarm in your home went off after the smoke has cleared. A green LED will be on for two seconds, then off for two seconds repeatedly until the alarm is reset.

One test/silence button makes the BRK 9120B easy to use, and a low-battery warning provides a visual and audible reminder that the backup battery needs to be replaced. These features, along with the BRK 9120B's ability to detect a fast, flaming fire, make it a great choice for your home.