Nest Protect Smoke and Carbon Monoxide Alarm

Last updated date: July 19, 2019

DWYM Score
9.4

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We looked at the top 1 Smoke Detectors and dug through the reviews from 9 of the most popular review sites including BestReviews, New York Times Wirecutter, Tom's Guide, Trusted Reviews, Pocket-lint, Top Ten Reviews, PC Magazine, CNET and more. Through this analysis, we've determined the best Smoke Detector you should buy.

Overall Take

The easy-to-install Nest Protect Alarm will alert you to both smoke and carbon monoxide in your home. This smart detector offers a combination of voice, siren and smartphone alerts. It can notify you of dangers whether you are asleep in bed or away from home. The smart voice alerts even tell you what is occurring and how you should proceed. In our analysis of 68 expert reviews, the Nest Nest Protect Smoke and Carbon Monoxide Alarm placed 1st when we looked at the top 10 products in the category. For the full ranking, see below.

Editor's Note July 19, 2019:
Checkout The Best Smoke Detector for a detailed review of all the top smoke detectors.

Expert Summarized Score
9.4
9 expert reviews
User Summarized Score
9.3
8,611 user reviews
Our Favorite Video Reviews
What experts liked
Like other Nest products, this combination smoke/CO2 detector is "smart" and compatible with numerous devices.
- BestReviews
The second-generation Nest Protect smoke and carbon monoxide alarm is the best smart smoke alarm for everyone because it’s the easiest to install and use, and it reliably and calmly alerts you to potential danger whether you're home or away using a combination of voice, siren, and smartphone alerts.
- New York Times Wirecutter
November 15, 2018 | Full review
The Nest Protect uses a split-spectrum sensor that Nest says is good at detecting both slow-smouldering fires as well as fast-burning ones.
- Tom's Guide
November 20, 2018 | Full review
Self-checks, Pathlight to help you find your way around and Works with Nest rules just add to the smart simplicity of this device.
- Trusted Reviews
December 12, 2018 | Full review
Nest Protect is also compatible with IFTTT, meaning you can do other clever things with it too.
- Pocket-lint
November 21, 2018 | Full review
Nest Protect goes a step further by adding voice alerts that calmly tell you what kind of danger is present, where it is and how to proceed.
- Top Ten Reviews
June 15, 2018 | Full review
The Nest Protect Smoke & Carbon Monoxide Alarm is another solid smart detector with ample functionality.
- Reviewed
December 12, 2018 | Full review
I particularly liked the Pathlight feature; when you walk under the Protect when the lights are out the light ring glows with a soft white light to guide your way.
- PC Magazine
January 17, 2014 | Full review
With a slimmer profile, a new in-app "silence" button that allows you to turn off smoke and CO alarms remotely (the original Nest Protect doesn't currently support this feature) and integration with the Nest Learning Thermostat , Nest Cam and IFTTT, this $99/£89 detector is the best connected one we've seen yet.
- CNET
July 27, 2015 | Full review
What experts didn't like
Requires some tech knowledge to set up and use.
- BestReviews
These alarms are expensive compared with a standard smoke and CO alarm.
- New York Times Wirecutter
November 15, 2018 | Full review
At $100, the Nest Protect is one of the most expensive, but also one of the most comprehensive, of the smart smoke detectors we've tested.
- Tom's Guide
November 20, 2018 | Full review
There’s no getting away from the fact that it’s expensive, however.
- Trusted Reviews
December 12, 2018 | Full review
It's an expensive bit of kit though – so you're probably wondering if it's worth the outlay and if all the bells and whistles are worthwhile.
- Pocket-lint
November 21, 2018 | Full review
Unfortunately, the device warranty is only two years, unlike the 10-year warranties of the First Alert Onelink and Kidde KN-COSM-B-RF.
- Top Ten Reviews
June 15, 2018 | Full review
The Nest Protect didn’t perform as well as some of its competitors in terms of responsiveness, taking 30 seconds or more after the alarm sounded to send notifications.
- Reviewed
December 12, 2018 | Full review
It has one other thing in common with the Learning Thermostat in that it carries a hefty price tag; at $129 (direct) it's significantly more expensive than what you'll pay for a typical smoke/CO alarm.
- PC Magazine
January 17, 2014 | Full review
The light bulb integrations weren't responsive enough for short smoke events, typically flashing several minutes after our test smoke dissipated.
- CNET
July 27, 2015 | Full review

From The Manufacturer

It’s time to expect more from your smoke alarm. Nest Protect has been redesigned from the inside out. It has a Split-Spectrum Sensor, tests itself automatically and lasts up to a decade. It’s also the first home alarm you can hush from your phone without any extra hardware required. And it tells you what’s wrong and can even alert your phone. Nest products are made to work together. And they can even work with lights, locks and other products in your home. The Nest Protect can alert the Nest Thermostat when it detects carbon monoxide and the Thermostat can turn off the furnace to try and reduce the leak while you get to safety. Nest is focused on making simple, human, delightful things. That’s how we’re creating the thoughtful home: A home that takes care of the people inside it and the world around it.

Overall Product Rankings

1. Nest Protect Smoke and Carbon Monoxide Alarm
Overall Score: 9.4
Expert Reviews: 9
2. First Alert Battery Operated Combination Smoke Alarm
Overall Score: 9.1
Expert Reviews: 7
3. Kidde Hardwire Smoke Alarm
Overall Score: 9.0
Expert Reviews: 9
4. Alert Pro 10 Year Battery Smoke Detector Fire Alarm
Overall Score: 8.9
Expert Reviews: 1
5. First Alert Interconnected Wireless Smoke Alarm
Overall Score: 8.4
Expert Reviews: 7
6. First Alert Dual-Sensor Smoke and Fire Alarm
Overall Score: 8.3
Expert Reviews: 7
8. Leeo Smart Alert Smoke/CO Remote Alarm Monitor
Overall Score: 7.8
Expert Reviews: 8
9. First Alert Smoke Alarm With Photoelectric Sensor
Overall Score: 7.4
Expert Reviews: 4
10. First Alert P1000
Overall Score: 6.5
Expert Reviews: 1

An Overview On Smoke Detectors

A properly installed, well-maintained and good quality smoke detector can literally save your life and the lives of those you love the most. Deciding the best brand and size for your home can be difficult since so much is riding on the little, plastic devices working as they should.

Kristin Forte/Simplemost Media

Battery-operated smoke detectors, such as the Alert Pro 10 Year Battery Smoke Detector, run solely on batteries, which are easy and affordable to install and replace. You can use a battery-operated detector in virtually any location. Provided the batteries are changed as needed, they will work during power outages as well.

Hardwired smoke detectors, like the Kidde i4618AC Hardwire Smoke Alarm, are connected directly into your home’s wiring. While they must be professionally installed, many have backup batteries that will last the lifetime of the alarm. So you can feel safe and not worry about remembering to change the batteries.

Kristin Forte/Simplemost Media

Many smoke detectors produce a loud, beeping or bleating alarm sound when triggered. This could certainly be ideal to alert you to fire or smoke danger. However, if you have heavy sleepers or young children in your home, they could be confused by or even sleep through the noisy alarm. Devices such as the Nest Protect Smoke and Carbon Monoxide Alarm use voice alerts to explain what is happening. They can awaken you or notify you with spoken, easy to understand warnings.

According to the CDC, at least 430 people die from accidental carbon monoxide poisoning each year in the United States. Considering a combination of smoke and carbon monoxide detector, such as the First Alert SCO501CN-3ST Battery Operated Combination Smoke and Carbon Monoxide Alarm, could result in double protection for your home and family. Carbon monoxide can come from leaky furnaces, poorly ventilated wood-burning stoves and many other sources commonly found in homes.

If you have a home security system, you might wish to consider purchasing a smoke detector that will integrate with your current configuration. This could give you increased protection, as many security providers monitor alarms like smoke detectors and can send emergency assistance even if you are away from home or unable to call for help.

Some smoke detectors are compatible with other smart home devices. For instance, devices such as the Nest Protect Smoke and Carbon Monoxide Alarm can be integrated with smart hubs, mobile apps and virtual assistants, like Google Home and Amazon Alexa-enabled devices.

Of course, when shopping for new smoke detectors for your home, office or other location, you must consider how much you want to spend. Fortunately, there are devices that will fit any budget, depending on features, projected lifespan and other attributes.

DYWM Fun Fact

The smoke detector was invented on accident. A Swiss physicist named Walter Jaeger attempted to create a sensor for detecting poison gas in the 1930s. When the device didn’t work as Jaeger intended it to, the frustrated scientist lit a cigarette. He noticed that the smoke moved the sensor’s meter, paving the way for modern smoke detectors.

About three decades later, the Atomic Energy Commission granted the first license to distribute smoke detectors, which were primarily used in industrial settings. These detectors used radioactive materials. By 1969, the AEC allowed homeowners to use smoke detectors. Although modern smoke detectors contain minute amounts of a radioactive material called americium-241, studies have shown them to be safe. In fact, a 2001 study showed that two of these smoke detectors in a home emit the same amount of radiation that people encounter daily from space and the earth.

Between 2005 and 2009, nearly two-thirds of all deaths resulting from
home fires occurred in homes with no smoke alarms or with smoke
alarms that were not working.

The Smoke Detector Buying Guide

  • Ionization smoke detectors are ideal for detecting small particles associated with quick-burning flames. However, things like steam or burnt food can cause them to go off, so you might not want to use these in or near your bathroom or your kitchen.
  • Photoelectric smoke detectors are highly rated for early detection of smoldering fires that emit lots of smoke and large particles. While they have fewer false alarms, making them a good choice for kitchens and steamy areas, they might not detect fast-burning flames as quickly.
  • Dual-sensor smoke detectors provide the benefits of ionization and photoelectric smoke detectors. Alternatively, you could install different types of devices in different areas of your home.
  • Look for a UL stamp on a smoke detector before you buy it. Underwriters Laboratories (UL LLC) is a global safety company that certifies, validates, tests, verifies, inspects and audits a wide range of products including smoke detectors. The UL certification mark is the single most accepted one in the United States.
  • Be sure to check the date on a smoke detector as well. Although recommendations can vary between makes and models, Consumer Reports recommends replacing smoke detectors every 10 years. Note that this should be 10 years after the date the device was manufactured, not the date it was installed. Fortunately, the manufacture date is printed on the underside of smoke detectors.
  • The National Fire Protection Association recommends installing smoke alarms inside every bedroom as well as outside each sleeping area. On floors without bedrooms, smoke detectors should be installed in living areas, such as the living room or den, and near stairways to upper levels as well.
  • While homes built to earlier standards might be exempt, every state has regulations and standards regarding where and how smoke detectors are installed in residential buildings. Check the regulations or recommendations for your state, as some states require that you make necessary upgrades before renting or selling your home.
  • The U. S. Fire Administration recommends testing your smoke detectors monthly. Put a monthly reminder on your phone or calendar to push the button on every detector in your home to make sure the alarm works properly.
  • USFA also recommends changing the batteries in battery-operated smoke detectors one to two times per year. An effective way to remember this is to replace them every time you change your clocks for Daylight Savings.