Carbon monoxide poisoning, unfortunately, is not such a rare accident that accompanies illiterate operation of a solid fuel or gas boiler, fireplace, gas stove, column. The spread of toxic substances can also occur if defective equipment is used. A frightening prospect, agree.
A miniature device - a carbon monoxide detector for the home will promptly warn the owners, eliminate negative consequences. It reliably detects the appearance of harmful substances in the air. Here you will learn how to choose it correctly, where to install it, how to track and respond to instrument readings.
In the article we presented, the principle of action is thoroughly analyzed, the types of sensors that ensure the safety of households are given. The installation process is carefully described, valuable recommendations are given. To optimize perception, the material is supplemented by visual illustrations and video tips.
Carbon monoxide and its negative impact
Carbon monoxide, or as it is also called CO, is a product of the oxidation of substances at high temperatures, in other words, carbon monoxide is formed during combustion. CO is always released in small amounts during cooking.
However, exceeding the permissible gas content in the room is fraught with severe health damage, and sometimes can be fatal.
Carbon monoxide annually takes the lives of thousands of people just because a person is not able to feel the threat before the onset of symptoms. This often happens when it’s too late to do anything.
Only special devices are capable of detecting a substance in the air, because the gas has no smell or color. In addition, it has a toxic effect on the body at the time of inhalation.
Once in the lungs, carbon monoxide comes into contact with hemoglobin, resulting in a reaction - carboxyhemoglobin. The substance prevents the saturation of blood cells with oxygen and causes hypoxia of body tissues.
To determine the presence of gas in the air, sensors are used, the scope of use of which is shown by a photo selection:
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Miniature Carbon Monoxide Detector
Installation near solid fuel heating units
Use in a professional kitchen
Location of the alarm device above the gas stove
The device is located near the gas column
Installation in boiler rooms of private houses
Carbon Monoxide Detector
Passenger and driver safety
As a result, the functioning of internal organs is disrupted, the nervous system and the brain are affected first.
The strength of the poisoning depends on the amount of carbon monoxide in the room:
- With a CO content of 0.08%, the first symptoms of poisoning are mild malaise and drowsiness.
- Then begins a headache and dizziness, a cough appears.
- In especially severe cases, there is a lesion of the mucous membranes of the nasopharynx, blanching of the skin and impaired heart function.
- With an increase in the level to 0.32% due to oxygen starvation, loss of consciousness, coma and paralysis occurs, with death occurring within half an hour.
- If the gas level rises to 1.2%, a person dies after 3 minutes.
Leakage occurs mainly in private buildings due to malfunctioning ventilation and chimney ducts. In addition, gas appliances, boilers and other equipment often fail, and as a result, the level of CO rises in the room.
An example is the most common case when poisoning occurs during sleep, because it is impossible to identify fumes by smell.
The gas used in everyday life and its combustion products cannot be detected without an appliance, as they have no color and smell
For salvation, the victim must be immediately taken to fresh air. It is also recommended to carry out deep ventilation of the lungs using an oxygen mask.
Often the cause of the leak is poor draft over an open flame source, an illiterate smoke exhaust system, or a gas stove malfunction. Living in the private sector, you must follow safety precautions when using heating elements.
When firing solid fuel boilers and furnaces, the shutter must not be closed ahead of time. In addition, the layout of some private houses also includes an attached garage, which can lead to excessive emission of waste and getting it into the residential part of the room. This is especially dangerous if the extension is poorly ventilated.
Emergency Protection
To eliminate false concerns about a possible leak, it is worthwhile to install a carbon monoxide identification system. The device will inform you about the air condition in the room and notify residents if toxic fumes are exceeded.
The detector does a good job of recognizing not only CO, but will also inform residents about the leakage of domestic gas. If a fire has already begun, the sensor will not recognize it, but in terms of preventive measures, it is indispensable.
The detector can be located on any vertical surface. Indication constantly reports on the status of the device and the level of toxic gases in the air
The device will instantly respond to changes in the chemical composition of air. According to the rules of installation, it is best not to install sensors in the immediate vicinity of open flame sources, but simply in the same room with heating equipment.
If the room is equipped with several heating units, it is necessary to organize a system of an equal number of detectors.
A wide range of manufacturers each year provides consumers with various carbon monoxide detection devices. Despite the fact that the form factor of each device is determined individually, the construction principle is almost always the same.
A photo introduces the principle of operation and the specificity of the sensor device:
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Device Batteries
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Carbon monoxide alarm
Indication of room temperature
A distinctive feature of the gas detection device is that the detector is not designed for smoke identification. So, in addition to the CO sensor, it is recommended to separately install the fire safety system.
The reaction of the sensor to exceeding the permissible parameters in the air is an audible signal that indicates the leakage of toxic gas. Before operation, it is necessary to read the instructions and test the device in an accessible, non-hazardous way, as Often people confuse the CO leak signal with a low battery sound indicator.
There are portable devices that have already become an integral attribute of fire safety in many countries, including Russia
Also, almost all devices have a function of notification of their own malfunction. The tone and interval of each sound is different. If the detector indicates a discharged battery, the sound in most cases has a clear jerky character and occurs 1 time per minute.
It is recommended to timely replace the battery, since the health and life of households depends on the proper functioning of the device. Mostly, replacement should be done no more than 2 times a year.
A constant squeak of the detector may indicate an increase in the level of toxins in the air, or a breakdown in equipment. In any case, an emergency service must be called immediately.
If poisoning symptoms are detected, you must immediately open all windows and leave the room, wait for the brigade on the street.
Specialists will check oxygen levels and identify leaks. If it still turns out that the signal is false, the detector will need to be replaced with a new one.
Some sensors for carbon monoxide and natural gas for the home are able to recognize even fairly safe substances with a high degree of evaporation. This primarily applies to alcohol and all alcohol-containing liquids.
When using alcohol-based cleaners, it is better to ventilate the room in order to avoid false alarms of the security system
With a high concentration of vapor, the system may give an alarm, but do not worry and immediately call the emergency service. Also, the operation of the detector can occur during cooking of some products, mainly subjected to the process of pickling.
This is mainly characteristic when the appliance is close to the hob. If this happens quite often, you should install the sensor away from the center of culinary procedures.
Types of air analyzers and their advantages
Increasingly, people are resorting to the use of certain models of household CO sensors. The most popular options include 3 main types of devices:
- Semiconductor detectors.
- Infrared sensors
- Devices with an electrochemical determination method.
In order to understand which of the devices will perfectly cope with the task of detecting dangerous gas, it will be suitable by the means and methods of installation, you need to understand their specifics.
# 1: Semiconductor Gas Detectors
The equipment of the first type is fundamentally different from the other two, because It works on the principle of chemical processes of interaction of atoms of substances. In most cases, dioxides are used as the active substance, namely carbon, tin and ruthenium.
Semiconductor signaling devices are connected directly to the power supply network. Mostly on the market you can hardly find such equipment with battery power
A method for determining toxins is to increase the conductivity of the affected air. As a result of this, contact is made between detector components. Then a mechanism is activated that signals the presence of carbon monoxide. The reaction takes place between atoms.
Sno2 (tin dioxide) or RuO2 (ruthenium dioxide). For the diffusion of atoms, it is necessary that the chemical elements are exposed to heat at a temperature of at least 250 degrees Celsius.
Clean air conductivity in a SnO device2 and RuO2 extremely small, so the device is active only if there is CO.
When heated from oxygen atoms under the influence of carbon monoxide, electrons begin to liberate. This process increases the conductivity of the detector capsule, due to which the sensor contacts are closed, and as a result, an alarm is triggered.
The voltage primarily depends on the amount of CO monoxide in the air. When the permissible level is exceeded, the voltage rises, so there are practically no false positives detected behind the semiconductor detector.
The only exceptions are cases when the device is located too close to the hearth of the fireplace, the firebox of the stove, the burner of the gas column. This is true for all types of equipment. Therefore, installation is recommended at a certain distance from the heating panels.
The design of the semiconductor sensor begins with a solid base. It is made of a polymeric material related to saturated polyesters. The case itself is made of stainless steel.The frontal part plays the role of an inlet where air affected by toxins enters.
In order to avoid the penetration of concomitant combustion substances, the detector housing contains a carbon layer. The latter serves as an absorbent. A double layer of stainless steel mesh is also provided to protect against physical contaminants such as dust.
The sensing element is located in the depth of the housing, under a layer of carbon filter. The voltage connects directly to the metal terminals on the other side of the capsule
In most cases, semiconductor sensors have 3 pins for connecting electricity. This is due to the fact that the design of the device contains 2 electrical circuits - for the heater, and for the element of metal dioxide.
This type of sensor is characterized by a high degree of wear resistance and a long service life. In addition, due to its small size, it consumes extremely little electricity, but by the level of CO determination, the device is on the list of the most efficient.
The video represents a semiconductor detector device, an example of a sensor’s operability:
# 2: Infrared analyzer
A completely different principle of operation is observed for infrared sensors. Here, air is used as an analyzer, which is then checked for the presence of CO by means of infrared radiation.
The main criterion that determines the level of carbon monoxide is the wave spectrum of the IR element, which absorbs carbon monoxide toxin molecules. Due to the fact that light is much more sensitive to external influences, sensors of this type successfully identify many pollutants, including methane.
The IR sensor is programmed to a specific CO level, which is considered a reference indicator. If the set limit is exceeded, an alarm is triggered.
The role of the sensitive element is performed by an LED or an incandescent filament. Such IR gas leakage sensors are called non-dispersive. The gas level is analyzed thanks to special filters that are configured to perceive only a specific spectrum.
Sensors of this type are not often used in our country. Due to the increased price, they are installed mainly in large institutions
In the event of a change in the chemical composition of the air, the element reacts, the light wave changes, and the detector detects the excess of the permissible level of the desired gas. The level of spectrum change is directly proportional to the percentage of chemical in the air.
Detectors of this type are often used not only in everyday life, but also as special devices for detecting toxic leaks. The selectivity of the equipment allows it to successfully scan the air for the presence of heavy gases such as ammonia and chlorine.
As for the design, the device is powered by means of connecting to a 220 V network. However, in most options for household devices provides the ability to work on batteries.
To indicate gas contamination, the device is equipped with a backlit display and an audible alarm system. If a gas leak is detected, the sensor will immediately give a clear jerky squeak, and the device’s monitor will blink.
# 3: Catalytic gas detectors
The main difference between electrochemical sensors is a rather small level of energy consumption. This is due primarily to the fact that the design of the device does not have a heating element, and the role of a sensitive substance is played by liquid electrolyte.
Therefore, the equipment may well do without connecting to the network, and work on rechargeable batteries. The structure of the sensor is such that an analysis of the state of the air is carried out by determining the level of oxidation of the substance inside the capsule of the device.As a rule, the medium of electrochemical reactions is a galvanic cell filled with a liquid alkaline solution (mainly potassium).
As practice shows, alkalis have some disadvantages, including a low resistance to carbon monoxide and a low shelf life.
Nevertheless, some manufacturers prefer to create an electrolytic medium using a mixture of acid solutions. Such a cell is much more resistant to the effects of external molecules and, as a result, is more durable.
The gas molecules (in this case, CO) are in contact with the electrode of the device, as a result of which a chemical oxidation reaction occurs. The electrolyte fixes the level of voltage that has arisen and translates this indicator into the level of gas content. The higher the percentage of fumes, the stronger the electrolysis.
The alarm control process is carried out by a small microcircuit, in which the specific level of the presence of fumes is registered. Therefore, according to a familiar principle, if the norm is exceeded, the sensor signals a danger.
The microcomputer inside the case accurately monitors voltage changes due to an increase in chemical reactions to CO
To maintain the purity of the active medium along with semiconductor sensors, a carbon filter is often placed in the housing, which traps unwanted molecules mixed with carbon monoxide. Thus, the effectiveness of the device is supported by a chemical system. protection, which reduces the likelihood of false activation.
Some models allow the replacement of damaged electrolyte and refill the galvanic capsule.
The advantages of catalytic sensors and the principle of their operation are demonstrated in the video:
Features of gas sensors
The form factor of some devices suggests the presence of a so-called electromagnetic relay, through which it is possible to connect the sensor to the gas pipe valve plug system.
The purpose of the system is mainly that such a sensor, when an alarm is triggered, instantly shuts off the gas supply in the pipe, thereby ensuring complete safety.
The relay can be connected as a separate element for controlling the damper. Some devices already have this system.
Modern equipment also provides a number of functions for warning of an emergency using a conventional mobile phone. In most cases, systems of this kind are characteristic of imported devices and it is rather difficult to meet them among domestic analogues.
Nevertheless, some manufacturers have taken care of the possibility of connecting additional GSM peripherals to notify the owner of the house via SMS.
The mobile signal transmitter looks like a regular chip. Connection is carried out according to the instructions supplied with the CO detector
Alarm Installation Process
Most detectors are equipped with a special mounting element, on which the device will be subsequently planted. It is recommended that you mount on a wall closer to the ceiling.
It should be noted that in European countries mounting a carbon monoxide detector on a wall next to a gas boiler or fireplace is a gross violation. Installation there is allowed to be carried out only on the ceiling, in contrast to the CIS, where the installation of the sensor often occurs at a distance of at least 1.5 m from the floor.
Since the sensors record not only carbon monoxide, but also natural gas, you need to understand some of the features of the installation. When arranging a gas alarm system, the device should be mounted at different heights.
If the house is connected to a pipeline with natural gas, the sensor must be placed closer to the ceiling. In the case of bottled gas - closer to the floor. This is explained by the different density of gaseous combustible substances.
Natural lighter than the liquefied balloon option. With a leak, it rises, while the balloon, on the contrary, first fills the lower levels of the room.
The choice of location and height for installing a gas presence sensor in the air depends on the type of gaseous fuel. To detect leaks of natural gas, the device is mounted at the top, to determine the propane-butane mixture is placed in the lower part of the room (+)
When organizing a gas leak prevention system, you should not rely 100% on the functions of the sensor. The device performs only the monitoring task and will not be able to protect the lives of people in the event of an emergency.
Before installation, check the ventilation system in the required order. If it is working, install it.
For self-checking traction, many advise to bring a lit lighter or candle to the ventilation hatch - this should never be done! It is better to use a piece of paper (e.g. toilet paper)
The process of connecting the sensor to the mains must be carried out exclusively by a competent specialist, otherwise there may be a malfunction in case of improper power supply. Do not neglect this rule, and it is better to contact a professional, because someone’s life depends on the success of the enterprise.
When choosing the location of the module, make sure that at least one of the sensors is located in the bedroom. This is important to consider. Indeed, most accidents associated with the leak of carbon monoxide occur during sleep.
If the house consists of several floors, it is necessary to provide an anti-fire system with each floor of the room through which the components of the autonomous heating system pass.
When mounting the sensor in the same room as the fire source, the minimum distance between the source and the sensor should be observed. As a rule, for an objective analysis of air, a distance of 4-5 m must be observed.
Some sensor models trigger when the air temperature rises above 50 degrees. Such a phenomenon takes place when a fire started in the room and the flame source is in close proximity to the device. At the same time, the amount of waste generated may still not reach the alarming mark.
The appliance should be located in such a place that nothing interferes with the flow of air. This is typical for cases where the detector mount is behind the curtain. Air circulation around the sensor is the main point that you need to pay attention to. Because some interior objects can block the inlet of the device and as a result, the system will not provide 100% protection.
There are several ways to check the performance of the analyzer. The easiest is to buy a special spray can with CO. By spraying it near the detector, you can verify that the installation operation is correct.
A carbon can can be found at any hardware store. When using, you need to be careful, because the substance is under pressure
It is worth observing some points when implementing this process. Firstly, in no case do you need to direct the aerosol stream directly onto the device. This is important, because the direct concentration of the substance is ten times higher than the actual amount needed to trigger the sensor.
Such an enterprise can either adversely affect the functionality of the sensor, or simply disable it. Most manufacturers insist on specialized equipment testing by qualified technicians. Naturally, the procedure is paid, but in this way you can be sure of the correct operation of the CO detector.
In order to avoid breakdowns, it is necessary to monitor the cleanliness of the room, reliable operation of ventilation, first of all, try to prevent dust accumulation on the sensor housing.
The main safety violations during the installation of gas equipment and recommendations on how to avoid carbon monoxide poisoning:
Carbon monoxide is dangerous because at high concentrations it can kill in a matter of minutes. Detectors take care of home safety by organizing round-the-clock monitoring of air composition. The choice of device depends only on personal preferences and the price of the device.
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