Carbon monoxide detector

The 5 best carbon monoxide detectors in 2023

Carbon monoxide is produced during incomplete combustion of carbon products such as wood, coal, gasoline, propane, natural gas and fuel oil. These energy sources are not dangerous when burned in an open, ventilated area, but they become dangerous in confined spaces such as a kitchen, basement, garage or motor home.

Odourless, colourless and tasteless, this gas (also known as CO) is difficult to detect without a sensor. Known as the silent killer, it can easily be countered by following some basic rules and equipping yourself with an approved carbon monoxide detector.

Our selection for the year 2023

There are many CO sensors on the market. In order to make your choice easier, we have limited our selection to 5 products that we believe are the best for your home in 2023.

1. Google Nest Protect smoke and carbon monoxide detector

The most efficient

The Google Nest Protect CO and Smoke Detector is a device with a dual-spectrum smoke sensor capable of detecting fires, as well as a carbon monoxide sensor to alert you if the presence of this deadly gas is detected. In the event of an alarm, the device will issue a voice message to tell you the nature and origin of the danger. It can also send an alert to your mobile, talk to you and even light your way in the dark.

The Google Nest Protect has a 10-year lifespan. You won't have to worry about forgetting to change its batteries: this detector notifies your phone when the batteries are low or when the sensor fails. Easy to install, this certified product (EN14604 and EN50291 standards) performs a series of 400 automatic tests every day to inform you of any problems. Intelligent, it distinguishes between water vapour from your shower and smoke.

2. X-Sense smoke and carbon monoxide detector

Our favourite

The X-Sense CO and Smoke Detector is a device with photoelectric and electrochemical CO sensors. These sensors operate independently of each other and trigger an alarm if dangerous smoke is present or if a certain level of carbon monoxide is present in the household air.

Equipped with an irreplaceable 10-year battery life, this detector will alert you to malfunctions and low battery levels. In the event of an alarm, an alarm of over 85dB will sound throughout the house, instantly alerting all occupants, even if they are asleep.

Equipped with an LCD screen, the digital display of this detector gives the level of carbon monoxide present in the ambient air in real time. This reliable, quality product complies with EN14604 and EN50291 standards. It has also passed BSI certification and is backed by a lifetime of service.

3. X-Sense Carbon Monoxide Detector

The best value for money

The X-Sense CO detector is a device with an electrochemical sensor. It has a superior performance in detecting CO in the air. In the presence of carbon monoxide, the detector emits an 85 dB alarm loud enough to alert everyone in your home. Equipped with a backlit LCD screen, the digital display of this product informs you in real time of the level of CO present in the air. You'll have no trouble reading it day or night.

Functional and easy to install, the X-Sense informs you in the event of a fault, low battery charge or end of life of the detector. Certified to EN50291, this product comes with a 60-day money back guarantee and a 5-year warranty on materials and service.

4. Smartwares Carbon Monoxide Detector

The SmartWares CO detector is a product designed for rooms from 20 to 40 m². Equipped with an electrochemical sensor, this device emits an 85 dB alarm as soon as it detects a carbon monoxide leak or a too high concentration of this gas in the domestic air.

Equipped with a digital display, this detector indicates the temperature (°C) as well as the level of carbon monoxide present in the air (ppm). Certified to EN50291, this product has a life span of 7 years, although you will need to change the battery every year to ensure it works properly.

5. Scondaor carbon monoxide detector

The Scondaor CO detector is a device with an electrochemical sensor that is certified and complies with the EN50291 standard. In the presence of carbon monoxide, the detector triggers an audible alarm of 85 dB. Equipped with an LCD screen, the digital display of the device also informs you in real time of the level of carbon monoxide present in the ambient air.

Equipped with AA batteries, the Scondaor will alert you when the battery is low. An end-of-life alarm is also included in this detector. As soon as it reaches 10 years of operation, it will sound to inform you that it is time to change it.

What is a carbon monoxide detector?

Not to be confused with a carbon dioxide detector (CO2), a carbon monoxide (CO) detector is a device designed to: measure the level of carbon monoxide present in the air and trigger an alarm when its concentration reaches a dangerous level. Some CO detectors can also be linked to a monitoring company to send help if needed in the event of an alarm.

For your safety, a carbon monoxide detector must be certified according to EN50291. This standard requires that the alarm be triggered according to specific thresholds:

  • Before 3 minutes for a concentration of 300 ppm CO in the air
  • Between 10 and 40 minutes for a concentration of 100 ppm CO in the air
  • Between 60 and 90 minutes for a concentration of 50 ppm CO in the air
  • Not before 120 minutes at 30 ppm CO in air

Is it mandatory?

At the time of writing (26/10/21), there is no legal obligation for an individual to have a carbon monoxide detector in the home (unlike the smoke detector). However, its use is still recommended. In fact, every year in France, no less than 1,000 households and more than 3,000 people are poisoned by carbon monoxide, which represents around thirty deaths.

Where to install it?

Carbon monoxide detectors should be placed high up and near the main rooms (kitchen, bedrooms, living room, near the garage). Each floor of your home should be equipped with a CO detector (including the basement). We recommend that you also refer to the product manual for further advice on installation.

Child playing with a gas cooker in the kitchen

How to maintain it?

To ensure that your CO detector works properly, it should be serviced regularly:

  • Test it frequently (once a month) using the button on the front
  • Replace the batteries according to the recommendations in the manual
  • Replace the sensor every two years or so, according to the manufacturer's instructions (some models intentionally set off an alarm when they expire).

How to detect carbon monoxide poisoning?

Carbon monoxide is a deadly gas because it binds to your red blood cells and robs your body of oxygen after passing through your lungs. The symptoms of inhalation are numerous: headaches, nausea, vomiting, shortness of breath, dizziness and fatigue.

When the level of carbon monoxide in the air reaches 150 ppm, new symptoms may appear such as disorientation and loss of consciousness. If left untreated, prolonged exposure to this gas can be fatal.

Dangers and how to protect yourself from carbon monoxide in the home
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How to avoid carbon monoxide poisoning?

You can limit the risks associated with carbon monoxide by following these tips:

  • Never heat your home with a gas cooker. It produces CO and can quickly fill your home with this deadly gas.
  • Do not operate your car in a closed garage.
  • Make sure that your home is well ventilated (do not block air outlets)
  • Beware of space heaters. They should only be used for a maximum of 2 hours at a time and in a ventilated room.
  • Do not use the following appliances inside your home: braziers, barbecues, generators.
  • Install a carbon monoxide detector on each floor of your home, near the bedrooms, garage and kitchen. It is easy to install and can save your life.
  • Air your home for at least 10 minutes a day, even in winter.

How does a CO detector work?

A CO detector is designed to sound an alarm when it detects a certain amount of carbon monoxide in the air. Once the alarm is triggered, the only way to stop it (without removing the batteries) is to ventilate the room thoroughly to remove the CO. There are 4 types of sensors for detecting carbon monoxide.

Expertbynet | How to install a battery-operated stand-alone CO detector?

Biomimetic sensor

The biomimetic sensor uses cyclodextrins, a chromophore and a number of metal salts. It works in a similar way to haemoglobin. In contact with CO, the molecules darken in proportion to the amount of carbon monoxide in the air. This change, visible to the naked eye, is subjected to an infrared photon source such as an infrared LED and then monitored using a photodiode. This type of sensor has a useful life of approximately 6 years. The alkaline battery should be changed after 2 - 3 years.

Electrochemical sensor

The electrochemical sensor uses a fuel cell to detect carbon monoxide. In the presence of the gas, an electric current is generated by the cell in proportion to the amount of gas present in the sensor's immediate environment. It is more efficient than other technologies for detecting CO and reacts accurately and linearly to the presence of carbon monoxide.

This type of sensor has a long life (about 5-10 years), as it requires only a low power supply to operate. Regarding the test button: it is only used to check the operational efficiency of the battery, the circuit and the alarm. The only way to check if the device is working properly in the presence of CO is to subject it to this gas. You can get a test spray (special CO) and check your device if necessary.

Optochemical sensor

The optochemical sensor consists of a block of chemical whose colour changes when exposed to CO. The chemical reaction changes from yellow to brown to black. Although economical, this type of sensor does not accurately determine the amount of CO in the air and offers only limited protection.

Metal oxide semiconductor

This type of sensor uses thin tin dioxide wires on an insulating ceramic base, controlled by an integrated circuit. In practice, the wires need to be heated to 400°C to detect carbon monoxide on the principle that oxygen increases the resistance of the tin dioxide while CO reduces it. This type of detector has to be tested once a year with a test gas and requires high energy consumption.