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This smoke and carbon monoxide alarm warns of danger by voice and siren, sends smartphone alerts to as many as six contacts, and has a self-check feature and a built-in night-light that changes colors if there’s an incident.

This smoke and carbon monoxide alarm warns of danger by voice and siren, and sends smartphone alerts to as many as six contacts. It also has a self-check feature and built-in night-light.

Google Nest Protect’s sensitivity to slow- and fast-burning fires, ability to self-test, sleek design, and straightforward app make it the best smart fire-safety device.

TechGearLab

If you currently have a Nest/Google smart home, we recommend the Google Nest Protect. This top-tier smart smoke detector features dual sensors to detect both flaming and smoldering fires, as well as an integrated carbon monoxide detector and escape light. The setup is simple and integrates with other Nest devices seamlessly, with convenient features like configuring your heating system to automatically turn off if it detects increased levels of carbon monoxide. 
While the Nest Protect does offer a lot of functionality, it comes with a pretty steep price tag. If you couple that price with the reality that it isn't compatible with other, less expensive alarms you might already have, you may end up needing to buy quite a few if you want a multi-alarm connected system. There are also some kinks that should hopefully be sorted out soon with the migration from Nest to Google accounts and the Works with Nest program. It's one of the best smart smoke detectors you can get if you are building a Google smart home or already have other Nest products.

Consumer Reports

CR’s take: The Google Nest Protect is another WiFi-enabled combination smoke-CO detector that performs well in our tests. It receives strong scores in our tests for low CO levels and smoldering fires, as well as a Good rating for detecting high CO levels. But like the First Alert Onelink above, it falls short in our flaming fire test. If you go with this detector, you may want to also consider purchasing a battery-powered ionization smoke detector, such as the Kidde RF-SM-DC. The Google Nest Protect comes in both battery-powered and hardwired versions and can interconnect with additional Nest Protects.

If your home is already equipped with other Google Nest products, we recommend the Google Nest Protect. This top-tier smart smoke detector features dual sensors to detect both flaming and smoldering fires, as well as an integrated carbon monoxide detector and escape light. The setup is simple and integrates with other Nest devices seamlessly, with convenient features like configuring your heating system to automatically turn off if it detects increased levels of carbon monoxide. 
While the Nest Protect offers lots of functionality, it comes with a pretty steep price tag. If you couple that price with the reality that it isn't compatible with other, less expensive alarms you might already have, you may end up needing to buy quite a few if you want a multi-alarm connected system. There are also some kinks that should hopefully be sorted out soon with the migration from Nest to Google accounts and the Works with Nest program. It's one of the best smart smoke detectors you can get if you are building a Google smart home or already have other Nest products.

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The Best Smart Smoke Alarm

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Google Nest Protect Smoke and Carbon Monoxide Detector Review

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CR’s take: For a smart smoke/CO detector that connects directly to WiFi, check out the First Alert Onelink Smart 1042135. This model receives strong scores in our tests for how well it detects high CO levels, low CO levels, and smoldering fires. However, it performs poorly in our flaming fires test because it lacks an ionization sensor. If you go with this detector, you may want to also consider purchasing a battery-powered ionization smoke detector, such as the Kidde RF-SM-DC. This First Alert comes in both battery-powered and hardwired versions, can interconnect with other compatible detectors, and works with Amazon Alexa and Apple HomeKit/Siri for voice control.

CR’s take: For a smart smoke/CO detector that connects directly to WiFi, check out the First Alert Onelink Smart 1042135. This model receives strong scores in our tests for high CO levels, low CO levels, and smoldering fires. However, it performs poorly in our flaming fire test because it lacks an ionization sensor. If you go with this detector, you may want to also consider purchasing a battery-powered ionization smoke detector, such as the Kidde RF-SM-DC. This First Alert comes in both battery-powered and hardwired versions, can interconnect with other compatible detectors, and works with Apple HomeKit/Siri as well as Amazon Alexa for voice control.

CR’s take: For a smart smoke and CO detector that connects directly to WiFi, check out the First Alert Onelink Smart 1042135. This model receives strong scores in all our tests, with the exception of flaming fires because it lacks an ionization sensor. If you go with this detector, you may want to also consider purchasing a battery-powered ionization smoke detector, such as the Kidde RF-SM-DC. This First Alert comes in both battery-powered and hardwired versions, can interconnect with other compatible detectors, and works with Amazon Alexa and Apple HomeKit/Siri for voice and app control.

Similar to our pick but also equipped with a carbon monoxide alarm, these photoelectric smoke alarms with voice alerts can interconnect and allow you to identify threats by location.

Smoke and CO Alarm Comparison