Nest Protect 2nd Generation Smoke + Carbon Monoxide Alarm review
Test scoreShow Context
- Smoke alarm
- Battery/Mains
- Smart optical smoke alarm

The Nest Protect 2nd Generation Smoke + Carbon Monoxide Alarm is a smart smoke alarm that’s two products in one - offering protection against CO and smoke. Launched back in 2017, it sounds as a traditional smoke alarm would do, while also sounding an alarm through your smartphone. As it doesn't come with a heat detection function, it's no longer suitable for homes in Scotland unless a separate interlinked smoke and heat alarm system is also installed. But does it do a good job of detecting smoke and how quickly does it sound the alarm? We tested it to find out, so read on for our full review.
What's included:- Pros and cons
Last checked by Which?
March 2022
First reviewed by Which?
June 2017

Technical specifications
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- 93%Highest score
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