Carbon monoxide is a deadly danger and it comes silently and unnoticed. By contrast, CO detectors can save lives because they warn in time of the invisible danger. Several hundred people are killed in Germany every year by carbon monoxide poisoning and many of these deaths would be avoided by a CO detector. In our guide on STERN.de read all about the dangers of carbon monoxide and how a CO detector can protect you and your family from the deadly danger. Among other things, you will learn in which cases the installation of a CO detector is necessary and what to look for when buying a carbon monoxide detector.
Top 10 CO Detectors
- Peak Level Button - Displays the peak CO level recorded by the alarm since it was last reset or unplugged
- Test Button Functions - Tests the unit for proper operation and resets the Carbon Monoxide alarm
- LED Operation - Blinking dot in lower right corner of display denotes normal operation
- 2 AA battery backup
- Low Battery Hush
- Event memory
- Digital Display - Displays the level of carbon monoxide the unit is sensing. Shows CO level in PPM (parts per million). Updates digital reading...
- Battery Operated - Provides best protection during power outages. Battery Safeguard makes it difficult to close the cover without batteries in the...
- Test/Reset Button - Tests unit's electronic circuitry & horn and resets the unit during alarm. Tests CO alarm circuit operation and allows you to...
- Keep your family safe with this easy to use plug in carbon monoxide alarm; it works with any standard outlet and also has a battery backup for...
- Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, no matter where the detector is placed in...
- Simple to use, with a single test/silence button; a loud 85 decibel alarm sounds when Carbon Monoxide levels reach dangerous levels. Low battery...
- Keep your family safe with this battery operated smoke and carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels,...
- Features an electrochemical Carbon Monoxide sensing technology as well as a photoelectric sensor that detects the larger particles of a smoldering...
- Indicator lights on the face of the unit display the presence of smoke or carbon monoxide, while an 85 decibel siren provides a clear, loud warning...
- Keep your family safe with this easy to use, battery operated carbon monoxide alarm; battery powered alarms provide continuous monitoring of CO...
- Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, no matter where the detector is placed in...
- A loud 85 decibel alarm sounds when CO levels reach dangerous levels
- Protects you and your family from two deadly threats: carbon monoxide and explosive gas.
- Sounder Alarm - The KN-COEG-3 offers a loud 85-decibel pulsing alarm that will sound to alert you to a potential problem.
- Digital Display - Displays the level of carbon monoxide the unit is sensing.
- This product adds a great value
- Product is highly durable and very easy to use
- This product is manufactured in China
- Keep your family safe with this hardwired smoke and carbon monoxide alarm; The battery backup means constant monitoring, even if there's a power...
- Features an electrochemical Carbon Monoxide sensing technology as well as an ionization sensor for smoke detection.
- Indicator lights on the face of the unit display the presence of smoke or carbon monoxide, while an 85 decibel siren provides a clear, loud warning...
- Help keep your family safe with this battery powered smoke and carbon monoxide detector alarm
- Unit uses wireless Z wave technology to send mobile alerts if the alarm goes off, so you are aware whether you're at home or away
- Certified to work with smart home systems such as ring alarm security system, Samsung Smart things, and Nexia Home Intelligence when connected to a Z...
What is a CO detector?
A carbon monoxide alarm or CO detector warns of elevated carbon monoxide levels in the air. The highly toxic gas can not only harmful to humans but also have fatal consequences and it is odourless, tasteless and colourless and is therefore not detectable without a meter. Similar to a smoke detector, but not to be confused with this, the CO detector is installed indoors and from a certain concentration of carbon monoxide in the air it reacts with an audible and often visual alarm and warns the inhabitants to inhale unnoticed the poisonous gas and to sustain serious health damage or even die from it. Carbon monoxide detectors are small and handy devices that are either wall-mounted or can be installed. They can be installed in living rooms, garages or basements and some models are also suitable for use in caravans, campers or on boats.
How does the CO detector work?
A carbon monoxide alarm is equipped with an electrochemical sensor that reacts to the CO concentration in the ambient air and triggers an alarm at certain threshold levels. The electrochemical sensor usually consists of tin oxide SnO 2, which reacts very quickly and sensitively to carbon monoxide. The carbon monoxide oxidizes the tin oxide directly, which changes the conductivity within the sensor. This results in a change in the resistance that is continuously analyzed and evaluated by the CO detector. The results of this analysis and thus the concentration of carbon monoxide measured in ppm are shown on the display of the CO detector.
The alarm of the carbon monoxide alarm is triggered whenever the carbon monoxide concentration in the room air reaches a critical level. However, since carbon monoxide is harmful even in small quantities, the alarm is triggered in most CO detectors not only when the CO concentration in the indoor air exceeds an acute critical level, but also, if, over a period of several minutes to hours constantly lower, harmful concentrations are measured. The thresholds at which the alarm is triggered are not arbitrarily chosen by the manufacturers of the CO detectors, but there are fixed DIN standards that must be complied with. The values are defined in the EN 50291 standard and must not be exceeded.
The alarm is triggered
- at a carbon monoxide concentration of 50 ppm (0.005%) after 60 to 90 minutes
- at a carbon monoxide concentration of 100 ppm (0.01%) after 10 to 40 minutes
- at a carbon monoxide concentration of 300 ppm (0.03%) in less than 3 minutes
The carbon monoxide detectors are operated by battery. Either replaceable alkaline batteries or permanently installed lithium long-life batteries are used. Some devices also work with rechargeable batteries. In addition to measuring the carbon monoxide content in the ambient air, some CO detectors display other parameters such as room temperature. They are also often equipped with a memory or memory function, as well as battery level and device life indicators.
Why is the CO detector so important?
Carbon monoxide, known in technical terms as carbon monoxide, is a colourless, odourless and tasteless gas. The human is therefore unable to notice an increased concentration of carbon monoxide in the air and react accordingly to it without tools. Exactly this fact makes the carbon monoxide so dangerous and in the worst case, it can become a death trap, because the gas is highly toxic. The respiratory poison, which enters the bloodstream via the lungs, is considered to be responsible for more than half of all deadly intoxications worldwide and a concentration of just over 1% in the ambient air leads to unconsciousness and death after only a few breaths.
But what makes the gas, which is also called the “silent killer”, so dangerous?
Carbon monoxide is composed of oxygen and carbon, and a carbon monoxide molecule is very similar to an oxygen molecule. When inhaled air containing a high concentration of carbon monoxide, carbon monoxide enters the bloodstream via the lungs, where it binds to the iron atoms of haemoglobin. The carbon monoxide binds more than 300 times more to the haemoglobin than the oxygen and thus hinders the transport of oxygen in the blood. Due to the insufficient oxygen saturation, it comes to health impairments to death, which can occur very quickly at a high CO concentration in the air. Unlike smoke, the gas is not noticed when inhaled. The type and intensity of the symptoms depends on the concentrations in which carbon monoxide is present in the air and how long the affected persons are exposed to this concentration.
The following symptoms are triggered by the inhalation of carbon monoxide:
- At a CO level of 35 ppm, headaches and dizziness occur within 6 to 8 hours
- At a CO level of 100 ppm, mild headaches occur within two to three hours
- At a CO level of 200 ppm, mild headaches and loss of judgment occur within two to three hours
- A CO level of 400 ppm causes severe headache within 1 to 2 hours
- A CO concentration of 800 ppm leads to unconsciousness within 2 hours. After only 45 minutes dizziness, cramps and nausea appear
- A CO concentration of 1,600 ppm leads to death within less than 2 hours. Dizziness and nausea start to appear after just 20 minutes, as does headache and increased heart rate
- A CO concentration of 3,200 ppm leads to death within 30 minutes. After only five to ten minutes dizziness, nausea and headache occur
- A CO value of 6,400 ppm causes respiratory arrest and death within less than 20 minutes. Dizziness, headaches and seizures occur after just one to two minutes, so that affected persons often can not escape the situation on their own
- A CO concentration of 12,800 ppm, which corresponds to 1.28%, leads to unconsciousness and then to death after only two to three breaths
At least from a carbon monoxide concentration of 800 ppm, it can easily lead to situations in which the affected people experience nausea, headache, cramps and other symptoms, but due to a disturbed judgment or unconsciousness are no longer able to, according to their own strength react and move away from the danger area. In particular, at lower CO concentrations and lighter symptoms, moreover, often no connection with carbon monoxide poisoning is produced so that people unknowingly continue to expose themselves to the danger.
Therefore, it is all the more important to be warned by a CO detector in time of the risk of carbon monoxide poisoning. If it comes to symptoms that may have been triggered by carbon monoxide poisoning, the most important thing is to immediately remove yourself and other affected persons from the possible source of carbon monoxide. In parallel, an ambulance should be called. The treatment for carbon monoxide poisoning includes ventilation with pure oxygen, which displaces carbon monoxide from the human bloodstream.
When should a CO detector be installed in any case?
The installation of a smoke detector is now legally required in Germany in all new buildings and in almost all federal states, even in existing real estate, if the rooms are rented out. But it looks quite different with the CO detector. There are no legal requirements here, although every year several hundred people are victims of carbon monoxide poisoning and the number of people injured by CO poisoning is much higher. It is therefore the responsibility of the individual to protect himself from carbon monoxide poisoning with a CO detector, both for the tenants and the owners.
While a smoke detector must be installed in every household in accordance with local regulations because it can cause fire anywhere, the installation of a CO alarm is only necessary where there is a real risk of increased levels of carbon monoxide in the air. So, to assess whether you need a CO Warner yourself, it’s important to know how carbon monoxide is made. Carbon monoxide is produced, inter alia, by the combustion of fossil fuels such as oil or gas or by the combustion of wood and usually when the fuels are burned under insufficient oxygen supply.
So if you have an oil heater, a gas heater or a gas boiler, a wood stove or a fireplace, a CO detector should not be missing in your household under any circumstances. Although proper operation of intact heating systems, gas-fired or wood-burning stoves does not result in the emission of carbon monoxide, various circumstances can cause the CO concentration in the indoor air to increase and, in the worst case, lead to carbon monoxide poisoning. Among the factors that can lead to an increased carbon monoxide concentration in indoor air include, among others
- Clogged chimneys Chimneys can be clogged by a bird’s nest, for example. If this is the case, the exhaust gases can no longer be drawn off the chimney and are directed back into the rooms
- Defective gas-fired heating or heating systems If gas-fired or heating systems are not properly maintained and maintained, defects can occur as a result of which carbon monoxide escapes and flows into the living space
- Incorrectly operated stoves Incorrectly operated stoves, where, for example, the supply of oxygen is not sufficient, can also lead to an increased carbon monoxide concentration due to incomplete combustion of the logs
Many circumstances, which can not be explained in detail here, can, therefore, lead to an increased concentration of carbon monoxide in the air in living spaces when burning oil, gas or wood. Although certain risk factors such as a clogged chimney through a doorman grid and regular inspections by the chimney sweep can be minimized, and regular maintenance and servicing of heating systems and gas heating reduces the risk of carbon monoxide getting into the indoor air, but the operation of such systems always remains a residual risk.
Since the emission of carbon monoxide from humans is not noticed before symptoms occur, it is therefore always strongly recommended to install a CO detector, if there is a possibility that carbon monoxide may escape. In addition to the operation of thermal baths, heating systems and stoves, there are a number of other situations in which carbon monoxide is produced and can be released in harmful concentration into the ambient air:
- In the improper combustion of propane gas, for example in a caravan, in a motorhome or on a boat
- By car exhaust, which is why in underground garages, but also in the private garage and in-car repair shops a CO detector should be installed
- When operating any type of internal combustion engine
- When grilling with charcoal
- When smoking shisha In shisha bars in Germany, it has already repeatedly come to injuries caused by carbon monoxide poisoning. The reason for this is the hookah coal, through which the tobacco or the herbal mixture of hookahs are heated. The slow combustion of coal produces carbon monoxide and inadequate ventilation can lead to a serious increase in CO concentration in indoor air. When visiting a shisha bar, be sure to check CO detectors and install a CO alarm at home if you would like to treat yourself to an Arab hookah
These types of CO detectors exist
There are a total of three device types for the CO detectors:
- Simple carbon monoxide detector
- Combined or hybrid detectors that work both as smoke detectors and as carbon monoxide detectors
- Networkable carbon monoxide detectors, which can be networked with each other or integrated into a smart home system
Many CO detectors are simple devices that measure only the carbon monoxide content in the ambient air. Therefore, they should not be confused with a smoke detector, because a conventional smoke detector does not measure the carbon monoxide content in the air, nor does a simple carbon monoxide detector start to smoke. The smoke detectors that are now legally required in rented new buildings and existing real estate in almost all federal states do not replace an additional CO detector in most cases. However, some devices act as so-called combination or hybrid detectors and warn both in smoke and in an increase in carbon monoxide.
In the course of the ever-increasing digitization and with the ever-increasing popularity of smart homes, carbon monoxide warners are now also on offer in the trade, which can be interconnected or integrated into a smart home system. When installing more than one of these devices, you can connect them together and if there is an incident, you will be notified, for example, by mobile phone. The devices can also be paired with compatible smart home components such as light bulbs that will flash in the event of an alarm. In addition to the carbon monoxide alarm, there are also the following warning devices, which must not be confused with the carbon monoxide alarm:
- Smoke detector: As already mentioned, the smoke detectors and CO detectors that are now required by law must not be confused with each other, as they measure different loads in the air. Although carbon monoxide is produced during a fire, a photo-optical smoke detector does not measure the presence of flue gases in the air. Instead, it measures the optical permeability of the air and, under certain circumstances, also triggers a strong evolution of steam. Thermo-optical smoke detectors additionally measure the temperature, but they also do not measure gases
- Fire detector: Fire detector is a generic term for various devices that can trigger an alarm in the event of a fire
- Gas Detector: Although carbon monoxide is a gas, it is not measured by a classic gas detector. Instead, gas detectors measure critical concentrations of flammable and explosive gases such as butane, propane or methane to protect against explosions
- Heat detectors: Pure heat detectors only react to the temperature. However, they are generally unsuitable for private households because at a temperature that causes the heat detector to trip, critical amounts of fumes have often already been generated and the alarm is therefore triggered much too late
Alternatives to the CO detector
There is no real alternative for the CO detector. If you operate equipment that is a potential source of carbon monoxide leakage, such as a wood-burning stove, gas boiler, pellet heater or oil heater, or use gas bottles while on holiday in the caravan or motorhome, you should install a carbon monoxide alarm. Whether you opt for a simple carbon monoxide detector or a hybrid detector, which also acts as a smoke detector, depends among other things on the local conditions, because sometimes smoke detectors and CO detectors should be installed in different positions. However, you should refrain from a carbon monoxide detector in any case, because the small device can save lives in case of doubt.
This is how the CO detector is installed
So that the carbon monoxide alarm can work as well as possible and false alarms are avoided, it is important to install it in the right place. Most devices already have an installation instruction in the instructions for use, indicating firstly the height at which the CO detector should be installed and the distance to the possible source of carbon monoxide emission. You should comply with this manufacturer’s instructions and also pay attention to the local structural conditions. In most cases, it is recommended that the CO alarm be located at a height of about 1.5 meters and at least 2 meters from the potential carbon monoxide source.
An installation under the ceiling, as is usual with a smoke detector, is not recommended for the carbon monoxide detector because you can not read the display there. Many CO detectors are provided with an indication in the operating instructions which provides information about the detection range. Depending on the size of the rooms and the number of possible carbon monoxide sources, it may, therefore, be necessary to install several CO detectors. The following mistakes should be avoided when installing a carbon monoxide detector:
- Do not place the CO detector too close to doors and windows, as incoming fresh air can falsify the measurement results
- Do not place the CO detector within a radius of 2 m around an extractor hood, as this can also falsify the measurement results
- If possible, do not place the CO detector in damp rooms
- Do not install the carbon monoxide detector in a position where it is subject to severe temperature changes
- Do not place the CO detector behind curtains, curtains or furniture
The installation of the carbon monoxide alarm is usually very simple and can be carried out by laymen themselves. If necessary, insert the batteries that are included in many cases and close the battery compartment. At the intended position on the wall now usually two to four holes must be drilled. With screws and dowels, which are also often included in delivery, the carbon monoxide alarm is then attached according to the instructions in the manual.
Important questions about the CO detector
What is the difference between a CO detector and a smoke detector?
A carbon monoxide detector uses an electrochemical sensor to measure the carbon monoxide content in the ambient air. A smoke detector, however, works mostly photo-optically or thermo-optically and reacts to smoke. He measures no harmful fumes, no carbon monoxide.
At what concentration is carbon monoxide harmful?
Carbon monoxide is very toxic and odourless as well as colourless, so it is not noticed in the breath. Already at a concentration of about 1.3% carbon monoxide in the air after a few breaths first, unconsciousness and then death occurs. Symptoms such as vomiting, dizziness or headache can occur at concentrations as low as 0.015% or 150 ppm. The gas is therefore very dangerous even in very small quantities.
What are the consequences of inhaling carbon monoxide?
The inhalation of carbon monoxide, which is unnoticed by humans, causes carbon monoxide molecules to become bound to the haemoglobin in the blood instead of oxygen molecules. At a critical carbon monoxide concentration of more than 1% CO in the breath, this quickly causes suffocation, as no oxygen can be taken up and transported.
How can carbon monoxide get into the breathing air?
Carbon monoxide is produced in almost all combustion processes, especially in the case of insufficient oxygen supply. So it can get into the breathing air through heating systems, gas heating or stoves. Carbon monoxide poisoning is usually an accident, but sometimes it is caused by negligence, such as when a charcoal grill is used indoors.
In which unit is the carbon monoxide measured?
Since carbon monoxide is toxic even in very small amounts, it is not measured in per cent or per thousand, but in parts per million (ppm). 1 ppm equals 0.0001% or 0.001 ‰
Can carbon monoxide detectors also measure other gases?
Carbon monoxide detectors usually do not measure other gases. This is partly because carbon monoxide is lighter than air and rises, while other gases such as butane or propane are heavier than air and sink. It is therefore difficult to reliably measure the concentration of various gases with one device. In combination with a smoke detector as a so-called combined or hybrid alarm device, the CO detector is combined with a photo or thermo-optical smoke detector and also measures no other gases.
What is the difference between carbon monoxide and carbon dioxide?
Carbon monoxide and carbon dioxide (CO and CO2) are sometimes confused. Carbon monoxide consists of a carbon atom and an oxygen atom, while carbon dioxide is formed from one carbon atom and two oxygen atoms. Among other things, carbon dioxide is emitted during respiration and it is produced by various chemical reactions as well as the combustion of fossil fuels and wood. Carbon monoxide is also produced by the combustion of fossil fuels and wood, and especially when the combustion takes place with too little oxygen.
Both gases are odourless, colourless and tasteless and toxic to humans. The risk of carbon monoxide, however, is much greater and lethal carbon dioxide poisoning is rather rare and occurs mainly in mines because carbon dioxide is heavier than air and collects especially in low-lying enclosed spaces. In addition, lethal carbon dioxide poisoning does not occur in the air of the breath until it reaches a concentration of around 8%, in contrast to carbon monoxide, where concentrations as low as 0.01% already cause discomfort.
What to do in the event of a carbon monoxide alarm?
If the alarm from the carbon monoxide alarm triggers, you should bring all persons in the house as soon as possible outdoors. Then alert the fire department and do not go back to the house to check on the right. You can not see, smell, or taste carbon monoxide leaking, and a few breaths may be fatal, depending on the concentration of carbon monoxide in the breath. In any case, wait until the fire brigade has checked the rooms with appropriate respiratory masks and measuring devices and releases them again.
How can false alarms of the CO detector be avoided?
Of course, a CO alarm can also cause a false alarm, but in principle, you should take any alarm seriously, because unlike a smoke alarm, you can not check whether it is a false alarm or not. You can reduce the risk of false alarms by using high-quality equipment and installing the carbon monoxide alarm according to the manufacturer’s instructions.
Is a carbon monoxide detector required by law?
The installation of a CO detector is not required by law. Unlike smoke detectors, owners do not need to equip their rented apartments with an appropriate warning device. Both as owner and a tenant, the responsibility to install a CO detector is up to you.
Maintenance and care of the CO detector
For the carbon monoxide detector to work reliably, it should be properly and regularly maintained and maintained. How exactly this care and maintenance looks like, however, varies from model to model and from manufacturer to manufacturer. In general, however, you should pay special attention to the following factors and check the smoke detector at regular intervals.
Device life: All CO detectors have a limited lifespan. Depending on the quality of the devices, it is between 3 and about 10 years. At the latest after expiration of the device service life, you should replace the CO detector. Some devices have an LED indicator that alerts you to the end of device life
Battery life: A CO detector is either equipped with a long-life lithium battery or with replaceable alkaline batteries. Be sure to replace replaceable batteries regularly and replace timely lithium-ion devices. Many devices have a battery level indicator to alert you to low battery levels
Operating temperature: For the carbon monoxide alarm to function reliably, the operating temperature should not be under or exceeded. Most devices operate at temperatures between 0 ° and 40 ° C
General damage: Check the carbon monoxide detector regularly for damage and, if available, use the test button for the function test
You must pay attention to this when buying a CO detector
A carbon monoxide alarm can save lives in the event of an emergency and therefore you should remember the benefits of the device again.
- A carbon monoxide alarm warns with increasing CO concentration, so you will not be surprised by the treacherous gas
- The warning comes early enough so you have enough time to escape
- Carbon monoxide detectors are already cheap to buy and often have a lifespan of 7 to 10 years
- The installation creates some effort
- The devices can trigger a false alarm
The most important advantage of the carbon monoxide detector is and remains that it can save lives and considering that several hundred people die each year in Germany from carbon monoxide poisoning, there is no reason not to use the CO detector. However, you should pay attention to a few things so that you decide on the right device when making your purchase. The most important we have put together here on STERN.de for you:
Service life: High quality carbon monoxide detectors have a lifespan of 7 to 10 years. CO detectors, which have a life of only three years or less, are often equipped with an inferior sensor. In order to ensure that you do not miss the time to replace the carbon monoxide alarm, you should also opt for a device that indicates the expiry of the device’s life by an LED.
Battery indicator: All CO detectors are powered by batteries. You have the choice between replaceable batteries and permanently installed long-life batteries. Permanently installed long-life batteries have the advantage that you can not forget the battery change. However, you should always make sure that the device has a charge gauge and notifies you in good time about low battery performance.
Self-test function: Many CO detectors have a so-called self-test function and check sensors and batteries at regular intervals. If there are problems with a component, they indicate a lack of functionality.
Long-term memory or memory function: With a long-term memory or a memory function, you can check whether there has been an increase in the CO concentration during your absence because the devices not only measure the carbon monoxide concentration in real-time but also record it for a certain period of time and to save.
Pre-alarm: Some devices give a pre-alarm even with a very low carbon monoxide concentration. So you are already warned about the occurrence of a harmful carbon monoxide concentration.
Volume: The volume of the alarm should be high enough so that an audible alarm is not missed. As a rule, the CO detectors have an alarm volume of 85 dB.
Alarm levels: Many CO detectors are equipped with different alarm levels. An elevated concentration of carbon monoxide in the air, even at low levels, is harmful for a prolonged period and causes symptoms such as headache, dizziness and nausea. Depending on the level of CO concentration, the devices, therefore, warn after a certain period of time.
Visual alarm: In order to support an audible alarm, the unit should also have an optical alarm, for example in the form of a red flashing LED. For example, hearing-impaired people do not miss the alarm, but even if you wear headphones, for example, you will not miss the alarm.
Display size: The display of the CO detector should be sufficiently large and readable in all lighting conditions. Some devices have clear pictograms in addition to the carbon monoxide concentration in ppm, with instructions such as an open window for airing or a skull symbol for instant escape.
Networking: If you already use smart home components or would like to receive a message on your smartphone, if there is an increase in carbon monoxide concentration, you should opt for a CO detector that can be networked and integrated into a smart home system. With these devices, you can also connect multiple CO detectors within a building.
Suitability: Not every CO detector is suitable for every location. Before you buy, make sure that the device is suitable for the intended location, such as a living room, garage or caravan.