Last updated: 16/10/2022

Carbon monoxide detectors sound an alarm in the event of an unusually rapid increase in carbon monoxide (CO) in the room air and thus effectively draw attention to a source of danger. They can often be real lifesavers. Carbon monoxide poisoning can not only lead to headaches, nausea and vomiting, but also to suffocation in severe cases. A carbon monoxide detector should therefore not be missing in any room with gas cookers, open fireplaces, oil, gas and wood stoves.

With our large carbon monoxide detector test 2022 we would like to help you find the best carbon monoxide detector for you. A comparison of the advantages and disadvantages of portable and fixed CO detectors will help you make your purchase decision.


  • Carbon monoxide detectors allow you to measure the level of carbon monoxide (CO) in the air in rooms with sources of danger such as fireplaces, cookers and gas cookers. They emit an alarm sound as soon as the CO level rises abnormally.
  • Basically, a distinction is made between fixed and portable carbon monoxide detectors. However, both variants are available with different additional functions and in different price classes.
  • Portable carbon monoxide detectors are particularly suitable if you want to protect yourself from carbon monoxide poisoning in various places such as your own car or mobile home, but also at home.

The Best Carbon Monoxid Detector: Our Picks

Guide: Questions you should ask yourself before buying a carbon monoxide detector

What is a carbon monoxide detector?

Carbon monoxide detectors, also called CO detectors, measure the level of carbon monoxide in the air and sound an alarm if the level rises sharply and is harmful to health. They are installed in rooms with sources of danger to prevent carbon monoxide poisoning.

A sensor in the device measures the concentration of the gas in the air. As soon as the critical value of 50 ppm (“parts per million”) CO is exceeded over a period of 60 to 90 minutes, the detector sounds an alarm.

<style=”font-weight: 400;”>

Carbon monoxide is invisible and odourless, which is why it is considered particularly dangerous.

Carbon monoxide is released during the combustion of gas, charcoal, oil and other fuels containing carbon. Because the gas is invisible and odourless, it is considered particularly dangerous.

In the event of poisoning, those affected usually experience headaches, nausea, vomiting and dizziness. As the gas is highly toxic, in bad cases it can also cause suffocation.

When is a carbon monoxide detector useful?

It makes sense to install a carbon monoxide detector in every closed room where there is a source of danger that emits this gas.


A carbon monoxide detector makes sense in kitchens equipped with a gas cooker and gas oven. The open source of danger makes the increased leakage of carbon monoxide more likely.
(Image source: / Janko Ferlič)

Sources of danger include gas cookers and ovens, open fireplaces, oil and wood stoves and propane-fuelled radiant heaters.

Ultimately, however, any type of machine or appliance that causes carbon monoxide to be released through the combustion of carbon-containing fuels is a source of danger.

Garages that house cars, motorbikes and other motor vehicles, as well as caravans and mobile homes, should also be equipped with a CO detector.

What does a carbon monoxide detector cost?

Good carbon monoxide detectors are available for as little as about 10 euros. Within this price range, they usually already have an additional temperature display.

CO detectors that promise a long service life and are also equipped with a smoke detector, for example, can be purchased for about 30 to 60 euros.

<style=”font-weight: 400;”>

Price Quality Special features
approx. 10 – 30 euros Good Display with temperature indicator
approx. 30 – 60 euros Very good Long service life, Including smoke detector
approx. 60 – 200 euros High quality Very long service life, Smart functions, Including smoke detector

However, there are also carbon monoxide detectors that can cost up to about 200 euros. These usually have additional functions, such as the possibility of operation via an app or other smart functions. A long service life is also often ensured with these detectors.

As a general rule, the quality of carbon monoxide detectors often increases with the price. However, this does not necessarily mean that the most expensive devices are the best choice.

How does a carbon monoxide detector differ from a smoke detector?

A carbon monoxide detector measures the density of carbon monoxide (CO) particles in the air and sounds an alarm if the level is too high. A smoke detector, on the other hand, only measures the optical refraction of the room air.

Feature Carbon monoxide detector Smoke detector
Legally mandatory No Yes
Measurement CO value in the room air Refraction of light in the room air
Installation 1.5 – 2 metres high on the wall On the ceiling

A smoke detector sounds an alarm if this light refraction is changed by increased particles in the air. This can be caused by water vapour and house dust, but also by smoke that is very harmful to health.

Unlike smoke detectors, CO detectors are not required by law. However, they are strongly recommended in rooms with sources of danger such as fireplaces and stoves.

It is also important to note that smoke detectors and carbon monoxide detectors cannot replace each other.

Decision section: What kind of carbon monoxide detectors are there and which is the right one for you?

When buying a CO detector, there are basically two alternatives you can choose between:

  • Portable carbon monoxide detector
  • Fixed carbon monoxide detector

Both types of carbon monoxide detectors are available with different additional functions and in different price ranges.

The two alternatives each have advantages and disadvantages that you should consider when making your choice. In the following section, we would like to make your decision easier.

What are the features of a portable carbon monoxide detector and what are its advantages and disadvantages?

A portable carbon monoxide detector is characterised by its mobility. You can use it at home, but also on the road and when travelling.

It is particularly suitable if there is no concrete source of danger in your home, but you still want to protect yourself against carbon monoxide poisoning. You can simply take it with you to protect yourself from increased CO content in the air while travelling.

<style=”font-weight: 400;”>

  • No installation necessary
  • mobile use

<style=”font-weight: 400;”>

  • Constant repositioning
  • safety depends on position

Your portable carbon monoxide detector can be used in many ways. You can use it in hotels, mobile homes, caravans, cars, on boats and in aeroplanes.

When taking your CO detector with you, however, you should always make sure that it is positioned correctly to ensure optimal measurement.

What are the features of a fixed carbon monoxide detector and what are its advantages and disadvantages?

A fixed carbon monoxide detector measures the CO concentration in the room air consistently and continuously from the same location. If your home has a wood-burning fireplace, gas stove or similar source of danger, this type of carbon monoxide detector is best suited for your home.

<style=”font-weight: 400;”>

  • Very affordable variants
  • Safe protection

<style=”font-weight: 400;”>

  • Necessary installation
  • Fixed location

When installing the CO detector, you should make sure that it is in the right place. Only then can the detector reliably measure the CO concentration in the air and sound the alarm in time. How and where to install it is usually explained in the enclosed instructions.

Carbon monoxide detectors that are permanently mounted can be bought at very reasonable prices. However, you can also use it only for a fixed location.

Buying criteria: You can use these criteria to compare and evaluate carbon monoxide detectors

In the following, we show you which aspects you can use to decide between the variety of carbon monoxide detectors.

With the help of these criteria, you can compare the different models with each other:

In the following sections, we will explain what is important for the individual criteria.

Room size

When buying your CO detector, the possible room coverage of the device is of crucial importance. Most carbon monoxide detectors are designed for a specific maximum room size and can only safely measure air quality within this.

Many devices cover a room size of 40 to 60 square metres. If you are looking for a carbon monoxide detector for a very large room, you should make sure that the model is designed for this.


Carbon monoxide detectors are suitable for certain room sizes. Particularly large indoor rooms must be equipped with suitable models accordingly.
(Image source: / Razlan Hanafiah)

The manufacturers usually indicate the room size on the respective models. You can often find it directly in the product description.

Service life

The service life of carbon monoxide sensors is limited to a certain period of time. Depending on the model, it varies between three and ten years.

In principle, models with a permanently installed lithium battery usually have a longer service life than models with a replaceable battery. However, if the battery is empty or defective, the latter have the advantage that only the battery needs to be replaced and not the entire device.

Ultimately, however, the service life of the CO sensors is decisive. Regardless of the battery, the devices should be replaced with new ones when their service life has expired.


The alarm of a carbon monoxide detector must have a volume of at least 85 dB.

Carbon monoxide detectors must have a volume of at least 85 dB (decibels). Only in this way can they effectively and almost inaudibly warn of a possible danger.

However, many devices have the option of setting the volume louder than the minimum specification. This is of great benefit in particularly large rooms or noisy environments.

Power supply

Carbon monoxide detectors are either battery or electrically powered. Electrically operated models are connected to the house power supply by means of a mains cable, which is included with the product. For battery-operated models, a distinction is also made between a permanently installed battery and a replaceable battery.

Devices that allow the battery to be replaced should display the battery level or warn of empty batteries via a sound. After all, a CO detector without a functioning battery cannot save lives.

The type of power supply can usually be found in the product description or on the manufacturer’s packaging.


Some carbon monoxide detectors are powered by simple alkaline batteries. They warn you with an indicator or a sound as soon as they are almost empty.
(Image source: / Claudio Schwarz)

Facts worth knowing about carbon monoxide detectors

Where and how do I install a carbon monoxide detector correctly?

When installing your carbon monoxide detector, it is important to consider the following things:

  • In every room with a source of danger: Every room in which there is a source of danger should be equipped with a CO detector.
  • Not in front of windows and doors: Fresh air often flows into the room in these places, which can lead to measurement inaccuracies and a malfunction of the detector.
  • Not in high humidity: High humidity can also cause sensors to measure inaccurately. Therefore, you should not place your CO detector directly above the cooker or in the bathroom.
  • Approx. 1.5 to 2 metres high: It is best to place your carbon monoxide detector on the wall at a height of 1.5 to 2 metres. Unlike smoke, carbon monoxide does not rise directly. It is about as heavy as air. Therefore, a CO detector that is mounted on the ceiling may not provide the best safety.
  • Carry out a test: After installing your CO detector, it is important to carry out a test. This is the only way to check that it is working properly.

A bracket and screws for mounting are usually supplied with the product. Instructions for the installation and the test can be found in the operating instructions of your device.

You can find a few tips on this topic in this video:

Which official standards must a carbon monoxide detector always comply with?

Since carbon monoxide detectors are true lifesavers, there are several relevant test seals for them. These provide information on whether the product complies with European directives and international standards.

Here you will find a more detailed explanation of the individual test seals:

  • VdS seal: The device has been tested for product-specific requirements and complies with European standards. VdS here means trust through safety.
  • CE seal: The model meets the applicable requirements of the European directives.

In addition, they are subject to the EU standard EN 50291, which obliges CO detectors to sound an alarm at certain values after a specified period of time to warn of increased CO concentrations in the air.

Image source: sbmh765/