Backup batteries need to be replaced annually.īelow are the best smoke and carbon monoxide detectors from our tests, arranged in alphabetical order, with hardwired and battery-powered picks for each type of detector: stand-alone smoke detectors, stand-alone CO detectors, combination smoke-CO detectors, and smart smoke-CO detectors that can send alerts to your smartphone. Both hardwired and plug-in detectors use a backup battery that will take over in the event of a power outage.

Plug-in detectors receive a constant flow of power from an outlet.

You’ll know you have hardwired detectors if there are wires connected to them that run into a wall or ceiling.

Hardwired detectors require special wiring for power that’s typically found only in newer or renovated homes.

They typically run on replaceable batteries (usually 9-volt or AA) or sealed lithium batteries that last 10 years.

Battery-powered detectors are wireless and can be placed anywhere.To determine the type you need, remove the detectors in your home from their mounts. Generally, detectors are battery-powered, hardwired, or plugged into an outlet. And for stand-alone CO detectors, we check the accuracy of the CO levels that they either display on their screens or read aloud via voice messages. Kidde Worry-Free Digital Plug-In Carbon Monoxide (CO) Alarm with 10-Year Battery Backup features sensing technologies that alert you and your family when. For interconnected CO alarms-which react as a group when any one of them is triggered-we expose them to precise low CO levels (100 ppm, or parts per million) and high CO levels (400 parts per million) to see how accurately and how quickly they detect the deadly carbon monoxide. In the lab, we expose detectors to both flaming fires and smoldering, smoky fires to see how well they detect fire and smoke, respectively. And to figure out the right detectors for your home, read the accompanying buying guide. “I have never tested a model that failed our fire and smoke tests, and it is reassuring to know that such critical devices actually work.”įor a look at all the models we’ve tested, see our smoke and carbon monoxide detector ratings. “We need to test detectors because some fail at CO detection, and there are differences in how quickly different models respond to CO,” says Bernie Deitrick, Consumer Reports’ test engineer for smoke and CO detectors. While most detectors look similar and come certified by a testing organization such as Underwriters Laboratory (UL) or Intertek Electrical Testing Labs (ETL), their efficacy isn’t necessarily the same.

According to the Centers for Disease Control and Prevention, more than 400 Americans die from accidental CO poisoning every year, and about 100,000 end up in emergency departments. A smoke and carbon monoxide detector’s ability to sense carbon monoxide (CO) can mean the difference between life and death.

Kidde carbon monoxide alarm