Carbon Monoxide Sensor for Home: Types of Leak Detection Devices

Poisoning with carbon monoxide, unfortunately, is not such a rare coincidence accompanying the illiterate operation of a solid fuel or gas boiler, fireplace, gas stove, column. The spread of a toxic substance can also occur if used equipment is used. Frightening prospect, agree.

A miniature device - a carbon monoxide sensor for the house will warn the owners in a timely manner, eliminate negative consequences. It fixes the appearance of harmful substances in the air. Here you will learn how to choose it correctly, where to install it, how to monitor and react to the readings of the device.

In the article submitted by us, the principle of operation is thoroughly analyzed, the types of sensors that ensure the safety of the household are given. The installation process is meticulously described, and valuable recommendations are given. To optimize perception, the material is supplemented with visual illustrations and video tips.

Carbon monoxide and its negative effects

Carbon monoxide, or CO, as it is also called, is the product of the oxidation reaction of substances at high temperatures, to put it simply - carbon monoxide is formed during the combustion process. CO is always released in small quantities during cooking.

However, exceeding the permissible rate of gas content in the room is fraught with serious damage to health, and sometimes can be fatal.

Only special devices are able to detect a substance in the air, because the gas is neither odor nor color. In addition, it has a toxic effect on the body at the time of inhalation.

Once in the lungs, carbon monoxide enters with hemoglobin, due to the reaction it turns out that carboxyhemoglobin. The substance prevents the process of 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 demonstrated by a photo selection:

As a result, the work of the internal organs is disrupted, the nervous system and the brain are the first to suffer.

The strength of the poisoning depends on the amount of carbon monoxide in the room:

1. When the CO content is 0.08%, the first symptoms of poisoning are mild malaise and drowsiness.
2. Then the headache and dizziness begins, a cough appears.
3. In severe cases, there is a lesion of the mucous membranes of the nasopharynx, blanching of the skin and disruption of the heart.
4. When the level rises to 0.32% due to oxygen starvation, loss of consciousness, coma and paralysis occur, and death occurs within half an hour.
5. If the gas level rises to 1.2%, the person dies after 3 minutes.

Substance leakage occurs mainly in private buildings due to faulty ventilation and chimney channels. In addition, gas appliances, boilers and other equipment often fails, and as a result, the level of CO rises in the room.

An example is the most common case where poisoning occurs during sleep, because the frenzy cannot be identified by smell.

For rescue, the victim must immediately be brought to fresh air. It is also recommended to deeply ventilate the lungs with an oxygen mask.

Often the cause of a leak is poor traction over an open-flame source, an illiterately constructed smoke exhaust system or a malfunctioning gas stove. Living in the private sector, you need to follow safety precautions when using heating elements.

When igniting solid fuel boilers and stoves, it is not possible to close the valve ahead of time. In addition, the planning of some private houses also includes an attached garage, which can lead to an excessive release of intoxication and getting it into the residential part of the room. In particular, it is dangerous if the extension is poorly ventilated.

Remedies for Emergency

To eliminate false concerns about a possible leak, it is worthwhile to put a system for identification of carbon monoxide. The device will report on the state of the air in the room and notify the residents in case of exceeding the rate of toxic fumes.

The detector copes well with the identification of not only CO, but also informs residents about the leakage of household gas. If the fire has already begun, the sensor does not recognize it, but in terms of preventive measures, it is irreplaceable.

The device will instantly respond to changes in the chemical composition of the air. According to the rules of installation, it is best not to install sensors in the immediate vicinity of sources of open fire, 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 the consumer with various devices for determining carbon monoxide. Despite the fact that the form factor of each device is determined individually, the construction principle is almost always the same.

With the principle of operation and the specifics of the sensor device acquaint the photo:

A distinctive feature of the gas detection device is that the detector is not designed to identify smoke. Therefore, in addition to the CO sensor, it is recommended to separately install the fire safety system.

The sensor's response to the excess of permissible parameters in the air is an audible signal, which indicates a leak of toxic gas. Before use, you must read the instructions and test the device in an affordable, non-hazardous way, because Often people confuse the CO leak signal with an audible low battery indicator.

Also, almost all devices have the function notifications of own fault. The tone and spacing of each sound is different. If the detector signals a discharged battery, the sound in most cases has a clear jerky character and occurs once a minute.

It is recommended that the battery be replaced in a timely manner, since the health and life of the household depends on the proper functioning of the device. Mostly, the replacement should be made no more than 2 times a year.

The constant squeak of the detector may indicate an increase in the level of toxins in the air, or else a breakdown of the equipment. In any case, you must immediately call the emergency service.

If you detect symptoms of poisoning, you must immediately open all the windows and leave the room, wait for the brigade on the street.

Experts will check the level of oxygen 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 of carbon monoxide and natural gas for the home are able to recognize even fairly safe substances with a high degree of evaporation. First of all, this applies to alcohol and all alcohol-containing liquids.

With a high concentration of vapors, the system may give an alarm, but do not worry and immediately call the emergency service. Detection may also occur during the cooking of some products, which are mainly subjected to the fermentation process.

This is mainly characteristic when the appliance is located 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 sensors CO. The most popular options include 3 main types of devices:

• Semiconductor based detectors.
• Infrared sensors.
• Devices with electrochemical method of determination.

In order to understand which of the devices will flawlessly cope with the task of identifying hazardous gas, it is suitable for the means and methods of installation, it is necessary to understand their specifics.

# 1: Semiconductor Gas Detectors

Equipment of the first type is fundamentally different from the other two, since 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.

The method of determining toxins is to increase the conductivity of the affected air. As a consequence, the contact components of the detector. Then the mechanism for the presence of carbon monoxide is triggered. The reaction takes place between the atoms.

Sno₂ (tin dioxide) or RuO₂ (ruthenium dioxide). To effect diffusion of atoms, it is necessary that the chemical elements be exposed to heat at a temperature of at least 250 degrees Celsius.

Conduct clean air in a SnO based device₂ and RuO₂ extremely small, so the device is active only if the presence of CO.

When heated from the atoms of oxygen under the influence of carbon monoxide begin to release electrons. This process increases the conductivity of the detector capsule, which causes the closure of the sensor contacts, 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 increases, so there are practically no false alarms for the semiconductor detector.

The only exceptions are when the device is too close to the hearth, the firebox, gas burner. This is true for all types of equipment. Therefore, it is recommended to install at some distance from the heating panels.

The semiconductor sensor design 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, to which the air toxins penetrate.

In order to avoid penetration of accompanying substances of burning, the detector case contains a coal layer. The latter serves as an absorbent. Also, to protect against physical pollutants, such as dust, a double layer of stainless mesh is provided.

In most cases, semiconductor sensors have 3 contacts 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 metal dioxide element.

The sensor of this type has a high degree of wear resistance and long service life. In addition, due to its small size, it consumes very little electricity, but in terms of CO determination, the device is on the list of the most efficient.

The video presents a semiconductor detector device, an example of sensor health:

# 2: Infrared analyzers

A completely different principle of operation is observed with infrared sensors. Here, the analyzer is air, which is then checked for the presence of CO by infrared radiation.

The main criterion for determining the level of carbon monoxide is the wave spectrum of the IR element, which absorbs the molecules of carbon monoxide toxins. 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 benchmark. If the set limit is exceeded, an alarm is triggered.

The role of the sensing element performs the LED or filament. Such IR gas leakage sensors are called non-dispersive. The gas level is analyzed using special light filters that are configured to perceive only a specific spectrum.

In case 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 change in the spectrum is directly proportional to the percentage of the 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 the 220 V network. However, in the majority of 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 peep, and the monitor of the device will begin to flash.

# 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 in the design of the device there is no heating element, and the role of a sensitive substance is performed by a liquid electrolyte.

Therefore, the equipment can easily do without connecting to the network, and work on battery-type batteries. The structure of the sensor is such that the analysis of the air condition is performed by determining the oxidation level 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, alkali has some drawbacks, including low resistance to carbon monoxide and low shelf life.

Nevertheless, some manufacturers prefer to create an electrolytic medium using a mixture of acidic solutions. Such a cell is much more resistant to the effects of foreign molecules and as a result - more durable.

The gas molecules (in this case, CO) are in contact with the device's electrode, as a result of which a chemical oxidation reaction occurs. The electrolyte fixes the level of the arising voltage and converts this indicator to the level of gas content. The higher the percentage of burnout, the stronger the electrolysis.

The process of controlling anxiety is carried out by a small microcircuit in which the specific level of the presence of intoxication is registered. Therefore, according to the already familiar principle, in case of exceeding the norm - the sensor signals about danger.

To preserve the purity of the active medium along with semiconductor sensors, a carbon filter is often placed in the housing, which detains 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 you to replace the deteriorated electrolyte and refill the electroplating capsule.

The advantages of catalytic sensors and the principle of their work are demonstrated in the video:

Features of gas availability sensors

The form factor of some devices assumes the presence of a so-called electromagnetic relay, by means of which it is possible to connect a sensor with a system of a gas valve plug.

The purpose of the system is mainly that such a sensor, when an alarm is triggered, instantly cuts off the gas supply in the pipe, thereby ensuring complete safety.

Modern equipment also provides a number of functions for notification of an emergency using a regular mobile phone. In most cases, systems of this kind are characteristic of imported devices and it is quite problematic 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 installation process of the alarm

Most of the detectors have a special fastening element on which the device will be landing later. It is recommended to mount on the wall closer to the ceiling.

It should be noted that in European countries, the mounting of the carbon monoxide sensor on the wall next to gas boiler or fireplace is a gross violation. Installation is allowed there only on the ceiling, in contrast to the CIS, where the sensor is often installed 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 installation. When arranging a gas alarm system, fixing the device should be carried out at different heights.

If the house is connected to a pipeline with natural gas, the sensor should 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 liquefied balloon option. In case of leakage, it rises upwards, while ballooning, on the contrary, first of all fills the lower levels of the room.

When organizing a gas leakage prevention system, you should not completely rely on the function of the sensor. The device performs only a monitoring task and cannot protect the lives of people in the event of an emergency.

Before installing in the required order should be checked ventilation system. If it is OK, install it.

The process of connecting the sensor to the mains should be carried out exclusively by a competent specialist, otherwise there may be problems with improper organization of power. Do not neglect this rule, and it is better to turn to a professional, because someone’s life depends on the success of the company.

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. After all, most accidents involving carbon monoxide leakage occur during sleep.

If the house consists of several floors, it is necessary to provide with an anti-theft system every floor of the room through which the components pass. autonomous heating system.

When mounting the sensor in the same room with a fire source, it is necessary to observe the minimum distance between the source and the sensor. As a rule, for an objective analysis of the air, you need to keep a distance of 4-5 m.

Some sensor models are triggered when the temperature rises above 50 degrees. Such a phenomenon occurs when a fire started in the room and the source of the flame is in close proximity to the device. At the same time, the amount of released frenzy may not yet reach the alarming mark.

The device should be located in such a place that nothing interferes with the air flow. This is typical for those cases where the detector mount is behind the curtain. Circulation of air around the sensor is the main point to which attention should be paid. Because some interior objects can block the inlet of the device and, as a result, the system will not provide 100% protection.

The analyzer can be tested in different ways. The easiest is to buy a special can of CO. Spraying it near the detector, you can ensure the correctness of the installation operation.

It is necessary to observe some points in the implementation of this process. First, in no case should you direct the jet of aerosol directly to the device. This is important, because the direct concentration of a substance is ten times higher than the actual amount needed to trigger the sensor.

Such an enterprise can either have a negative impact on the functionality of the sensor, or simply disable it. Most manufacturers insist on specialized testing equipment from qualified technicians. Naturally, the procedure is paid, but this way you can be sure that the CO detector works correctly.

In order to avoid damage, you need to monitor the cleanliness of the room, trouble free ventilation, first of all try to avoid the accumulation of dust on the sensor housing.

Conclusions and useful video on the topic

The main violations of safety precautions when installing 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. The detectors will take care of home safety by organizing round-the-clock monitoring of the air composition. The choice of device depends only on personal preferences and price of the device.

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