Colorless and odorless. The most important regulator of blood circulation and respiration. Non-toxic. It wouldn't have happened without him buns and pleasantly tart carbonated drinks. From this article you will learn what carbon dioxide is and how it affects the human body...

Most of us do not remember well the school course in physics and chemistry, but we know: gases are invisible and, as a rule, intangible, and therefore insidious. Therefore, before answering the question of whether carbon dioxide is harmful to the body, let's remember what it is.

Earth Blanket

CO2 is carbon dioxide. It is also carbon dioxide, carbon monoxide (IV) or carbonic anhydride. Under normal conditions, it is a colorless, odorless gas with a sour taste.

Under atmospheric pressure, carbon dioxide has two state of aggregation: gaseous (carbon dioxide is heavier than air, poorly soluble in water) and solid (at –78 ° C it turns into dry ice).

Carbon dioxide is one of the main components environment. It is found in the air and underground mineral waters, is released during the respiration of humans and animals, and is involved in plant photosynthesis.

Carbon dioxide actively influences the climate. It regulates the heat exchange of the planet: it transmits ultraviolet radiation and blocks infrared radiation. In this regard, carbon dioxide is sometimes called the Earth's blanket.

O2 - energy. CO2 - spark

Carbon dioxide accompanies a person throughout his life. Being a natural regulator of respiration and blood circulation, carbon dioxide is an integral component of metabolism.

Inhaling about 30 liters of oxygen per hour, a person emits 20–25 liters of carbon dioxide.

By inhaling, a person fills the lungs with oxygen. At the same time, a two-way exchange occurs in the alveoli (special “bubbles” of the lungs): oxygen passes into the blood, and carbon dioxide is released from it. The man exhales. CO2 is one of the end products of metabolism. Figuratively speaking, oxygen is energy, and carbon dioxide is the spark that ignites it.

Carbon dioxide is no less important for the body than oxygen. It is a physiological stimulant of respiration: it affects the cerebral cortex and stimulates the respiratory center. The signal for the next breath is not a lack of oxygen, but an excess of carbon dioxide. After all, metabolism in cells and tissues is continuous, and its end products must be constantly removed.

In addition, carbon dioxide affects the secretion of hormones, enzyme activity and the speed of biochemical processes.

Gas exchange equilibrium

Carbon dioxide is non-toxic, non-explosive and absolutely harmless to people. However, the balance of carbon dioxide and oxygen is extremely important for normal life. Lack and excess of carbon dioxide in the body leads to hypocapnia and hypercapnia, respectively.

Hypocapnia - lack of CO2 in the blood. It occurs as a result of deep, rapid breathing, when more oxygen enters the body than needed. For example, during too intense physical activity. The consequences can vary: from mild dizziness to loss of consciousness.

Hypercapnia - excess CO2 in the blood. A person inhales (together with oxygen, nitrogen, water vapor and inert gases) 0.04% carbon dioxide, and exhales 4.4%. If you are in a small room with poor ventilation, the concentration of carbon dioxide may exceed the norm. As a result, headache, nausea, and drowsiness may occur. But most often hypercapnia accompanies extreme situations: a malfunction of the breathing apparatus, holding one’s breath under water, and others.

Thus, contrary to the opinion of most people, carbon dioxide in the quantities provided by nature is necessary for human life and health. In addition, it has found wide industrial application and brings many practical benefits to people.

Sparkling bubbles at the service of chefs

CO2 is used in many fields. But, perhaps, carbon dioxide is most in demand in the food industry and cooking.

Carbon dioxide is formed in yeast dough under the influence of fermentation. It is its bubbles that loosen the dough, making it airy and increasing its volume.

Various refreshing drinks are made using carbon dioxide: kvass, mineral water and other sodas beloved by children and adults. These drinks are popular with millions of consumers around the world, largely due to the sparkling bubbles that burst so funny in the glass and “prick” the nose so pleasantly.

Can the carbon dioxide contained in carbonated drinks contribute to hypercapnia or cause any other harm to a healthy body? Of course not!

Firstly, the carbon dioxide used in the preparation of carbonated drinks is specially prepared for use in the food industry. In the quantities in which it is contained in soda, it is absolutely harmless to the body of healthy people.

Secondly, most of the carbon dioxide evaporates immediately after opening the bottle. The remaining bubbles “evaporate” during the drinking process, leaving behind only a characteristic hiss. As a result, a negligible amount of carbon dioxide enters the body.

“Then why do doctors sometimes prohibit drinking carbonated drinks?” - you ask. According to the candidate of medical sciences, gastroenterologist Alena Aleksandrovna Tyazheva, this is due to the fact that there are a number of diseases of the gastrointestinal tract for which a special strict diet is prescribed. The list of contraindications includes not only drinks containing gas, but also many food products. A healthy person can easily include a moderate amount of carbonated drinks in his diet and allow himself a glass of cola from time to time.

Conclusion

Carbon dioxide is necessary to support the life of both the planet and an individual organism. CO2 affects the climate, acting as a kind of blanket. Without it, metabolism is impossible: metabolic products leave the body with carbon dioxide. It is also an indispensable component of everyone’s favorite carbonated drinks. It is carbon dioxide that creates playful bubbles that tickle your nose. At the same time, it is absolutely safe for a healthy person.

Soda, volcano, Venus, refrigerator - what do they have in common? Carbon dioxide. We have collected for you the most interesting information about one of the most important chemical compounds on the ground.

What is carbon dioxide

Carbon dioxide is known mainly in its gaseous state, i.e. as carbon dioxide with simple chemical formula CO2. In this form it exists under normal conditions - when atmospheric pressure and “normal” temperatures. But at increased pressure, above 5,850 kPa (such as, for example, the pressure at a sea depth of about 600 m), this gas turns into liquid. And when strongly cooled (minus 78.5°C), it crystallizes and becomes so-called dry ice, which is widely used in trade for storing frozen foods in refrigerators.

Liquid carbon dioxide and dry ice are produced and used in human activity, but these forms are unstable and easily disintegrate.

But carbon dioxide gas is distributed everywhere: it is released during the respiration of animals and plants and is an important component of chemical composition atmosphere and ocean.

Properties of carbon dioxide

Carbon dioxide CO2 is colorless and odorless. Under normal conditions it has no taste. However, if you inhale high concentrations of carbon dioxide, you may experience a sour taste in your mouth, caused by the carbon dioxide dissolving on mucous membranes and in saliva, forming a weak solution of carbonic acid.

By the way, it is the ability of carbon dioxide to dissolve in water that is used to make carbonated water. Lemonade bubbles are the same carbon dioxide. The first apparatus for saturating water with CO2 was invented back in 1770, and already in 1783 the enterprising Swiss Jacob Schweppes began industrial production of soda (the Schweppes brand still exists).

Carbon dioxide is 1.5 times heavier than air, so it tends to “settle” in its lower layers if the room is poorly ventilated. The “dog cave” effect is known, where CO2 is released directly from the ground and accumulates at a height of about half a meter. An adult, entering such a cave, at the height of his growth does not feel the excess of carbon dioxide, but dogs find themselves directly in a thick layer of carbon dioxide and are poisoned.

CO2 does not support combustion, which is why it is used in fire extinguishers and fire suppression systems. The trick of extinguishing a burning candle with the contents of a supposedly empty glass (but in fact carbon dioxide) is based precisely on this property of carbon dioxide.

Carbon dioxide in nature: natural sources

Carbon dioxide is formed in nature from various sources:

• Respiration of animals and plants.
  Every schoolchild knows that plants absorb carbon dioxide CO2 from the air and use it in the processes of photosynthesis. Some housewives try to indoor plants make up for shortcomings. However, plants not only absorb, but also release carbon dioxide in the absence of light - this is part of the respiration process. Therefore, a jungle in a poorly ventilated bedroom is not very good idea: CO2 levels will rise even more at night.
• Volcanic activity.
  Carbon dioxide is part of volcanic gases. In areas with high volcanic activity, CO2 can be released directly from the ground - from cracks and fissures called mofets. The concentration of carbon dioxide in valleys with mofets is so high that many small animals die when they get there.
• Decomposition of organic matter.
  Carbon dioxide is formed during the combustion and decay of organic matter. Large natural emissions of carbon dioxide accompany forest fires.

Carbon dioxide is “stored” in nature in the form of carbon compounds in minerals: coal, oil, peat, limestone. Huge reserves of CO2 are found in dissolved form in the world's oceans.

The release of carbon dioxide from an open reservoir can lead to a limnological catastrophe, as happened, for example, in 1984 and 1986. in lakes Manoun and Nyos in Cameroon. Both lakes were formed on the site of volcanic craters - now they are extinct, but in the depths the volcanic magma still releases carbon dioxide, which rises to the waters of the lakes and dissolves in them. As a result of a number of climatic and geological processes the concentration of carbon dioxide in waters exceeded critical value. A huge amount of carbon dioxide was released into the atmosphere, which went down the mountain slopes like an avalanche. About 1,800 people became victims of limnological disasters on Cameroonian lakes.

Artificial sources of carbon dioxide

The main anthropogenic sources of carbon dioxide are:

• industrial emissions associated with combustion processes;
• automobile transport.

Despite the fact that the share of environmentally friendly transport in the world is growing, the vast majority of the world's population will not soon have the opportunity (or desire) to switch to new cars.

Active deforestation for industrial purposes also leads to an increase in the concentration of carbon dioxide CO2 in the air.

CO2 is one of the end products of metabolism (the breakdown of glucose and fats). It is secreted in the tissues and transported by hemoglobin to the lungs, through which it is exhaled. The air exhaled by a person contains about 4.5% carbon dioxide (45,000 ppm) - 60-110 times more than in the air inhaled.

Carbon dioxide plays a large role in regulating blood flow and respiration. An increase in CO2 levels in the blood causes the capillaries to dilate, allowing large quantity blood, which delivers oxygen to tissues and removes carbon dioxide.

Respiratory system is also stimulated by an increase in carbon dioxide content, and not by a lack of oxygen, as it might seem. In reality, the lack of oxygen is not felt by the body for a long time and it is quite possible that in rarefied air a person will lose consciousness before he feels the lack of air. The stimulating property of CO2 is used in artificial respiration devices: where carbon dioxide is mixed with oxygen to “start” the respiratory system.

Carbon dioxide and us: why CO2 is dangerous

Carbon dioxide is necessary for the human body just like oxygen. But just like with oxygen, an excess of carbon dioxide harms our well-being.

A high concentration of CO2 in the air leads to intoxication of the body and causes a state of hypercapnia. With hypercapnia, a person experiences difficulty breathing, nausea, headache, and may even lose consciousness. If the carbon dioxide content does not decrease, then oxygen starvation occurs. The fact is that both carbon dioxide and oxygen move throughout the body on the same “transport” - hemoglobin. Normally, they “travel” together, attaching to different places on the hemoglobin molecule. However, increased concentrations of carbon dioxide in the blood reduce the ability of oxygen to bind to hemoglobin. The amount of oxygen in the blood decreases and hypoxia occurs.

Such unhealthy consequences for the body occur when inhaling air with a CO2 content of more than 5,000 ppm (this can be the air in mines, for example). To be fair, in ordinary life we practically never encounter such air. However, a much lower concentration of carbon dioxide does not have the best effect on health.

According to some findings, even 1,000 ppm CO2 causes fatigue and headaches in half of the subjects. Many people begin to feel stuffiness and discomfort even earlier. With a further increase in carbon dioxide concentration to 1,500 – 2,500 ppm critically, the brain is “lazy” to take the initiative, process information and make decisions.

And if a level of 5,000 ppm is almost impossible in Everyday life, then 1,000 and even 2,500 ppm can easily be part of reality modern man. Ours showed that in rarely ventilated school classrooms, CO2 levels remain above 1,500 ppm much of the time, and sometimes jump above 2,000 ppm. There is every reason to believe that the situation is similar in many offices and even apartments.

Physiologists consider 800 ppm to be a safe level of carbon dioxide for human well-being.

Another study found a link between CO2 levels and oxidative stress: the higher the carbon dioxide level, the more we suffer from oxidative stress, which damages our body's cells.

Carbon dioxide in the Earth's atmosphere

There is only about 0.04% CO2 in the atmosphere of our planet (this is approximately 400 ppm), and more recently it was even less: carbon dioxide crossed the 400 ppm mark only in the fall of 2016. Scientists attribute the rise in CO2 levels in the atmosphere to industrialization: in the mid-18th century, on the eve of the Industrial Revolution, it was only about 270 ppm.

Carbon dioxide.
The effect on humans of increased carbon dioxide content in inhaled air

Let me start with the fact that health depends on the energy that passes through the body. It depends on how freely energy moves through energy channels. And freedom depends on the state of our psyche. Many healers talk about this, give a variety of healing systems, and what’s interesting is that all systems work and heal. They are united by one circumstance - if you want to heal, work on yourself. Healers open the door, but everyone must enter independently.

But I want to tell you about another healer who even heals the lazy. His name is Konstantin Pavlovich Buteyko. He claims that carbon dioxide is good for us, that an increased content of carbon dioxide in the air that a patient breathes can cure 150 diseases. I believe him only because I checked it on myself. I'll start in order.

Buteyko himself says that his first thoughts on this matter appeared when he was in his 3rd year of medical school (MSU):
- Undertook an internship in therapy. I noticed how patients who are forced to breathe deeply while listening to the lungs experience a sharp deterioration in their condition: dizziness, asthma attacks, angina pectoris, even fainting, respiratory arrest and convulsions. It was especially amazing when I examined my first patient and, like a meticulous student, carefully listened to his lungs. In this case, the patient must breathe deeply. And so, after a few minutes, this patient, a heavyweight athlete, fell “like someone shot.” I rushed to him - it was a lifeless corpse: pale, pointed facial features. . . The impression is that the person died! It happened so quickly, because I listened to him for 2-3 minutes, no more. I jumped out into the corridor and shouted that he was dying healthy man. “Even our sick people don’t die!” - the doctor calmly noted and looked into the room. “It was you who “suffocated” him. At this time, the patient turned a little blue, took a breath, a second, opened his eyes, stood up and asked: “What happened to me?” I couldn't answer!

The assistant further explained that this was due to deep breathing, which oversaturated the body with oxygen and caused the person to faint. Buteyko was indignant and began to argue that deep breathing cannot be harmful, since it increases the oxygen content in our body. Having not received a clear explanation, he began searching in the literature and investigated this issue himself, creating his own experiments.

He found that back in 1949 it was known that deep breathing has a negative effect on the body!!!

Firstly- DEEP BREATHING DOES NOT INCREASE THE OXYGEN CONTENT IN THE ARTERIAL BLOOD. Wow!
Secondly- deep breathing removes carbon dioxide and reduces its content in the lungs, blood and tissues. Well, maybe this is why deep breathing is useful. However, low carbon dioxide content leads to stimulation of the nervous system. This leads to insomnia, irritability, and memory impairment. Any disruption of the nervous system leads to turbulence in the energy flow in the energy channels. This creates a traffic jam, the flow of the lifestream is disrupted, which leads to illness.

Buteyko himself says further:
- At the body level, a decrease in carbon dioxide causes a decrease in the concentration of pH (hydrogen ions) in the blood, shifting the reaction to the alkaline side, because a solution of carbon dioxide is a weak acid. And this inevitably leads to metabolic disorders. Metabolism is the basis of life. The foundation is broken, therefore life declines

To put it simply, it turned out that without carbon dioxide, the blood is not saturated with oxygen. No matter how much oxygen there is in the lungs, if there is a lack of carbon dioxide, oxygen does not enter the blood.

Saturation of blood with oxygen is the main purpose of yoga hosannas and pranoyama. Each pose (hosanna) is recommended for a particular illness. If your throat hurts, do the lion pose, the grasshopper pose is good for the kidneys, etc.

It turned out that the harm of deep breathing is associated with the loss of carbon dioxide. If carbon dioxide in the lungs is sharply reduced, paralysis of all metabolic functions occurs and the death of body cells occurs. Many laboratory mice died this way (may their memory be blessed). And if you reduce it a little - as happens with deep breathing - the consequences will be milder, but the body’s immune forces will weaken. Deep breathers begin to react to any infection, suffer from frequent colds, can catch tuberculosis, rheumatism, sinusitis, tonselitis, asthma... Buteyko lists 150 types of diseases, which he called: deep breathing diseases.

Historical facts

So, deep breathing drains carbon dioxide and this leads to loss of oxygen in the blood, which leads to diseases. But why did scientists decide that carbon dioxide is poison for our body?

Yes, because, considering the development of the Earth from the beginning of the origin of life, it was clear that it was oxygen that made it possible for such a thing to appear a large number animals. We sing glory to oxygen. The planet's atmosphere was initially saturated with carbon dioxide and other under-oxidized products. There was practically no oxygen, but plants appeared and began to absorb CO2 and release oxygen.

Timiryazev established that plants feed on carbon dioxide from the air, adding water in the photosynthesis reaction, throwing out oxygen as waste. The composition of the atmosphere began to change, and animals began to appear. Animals feed on plants, which in turn feed on carbon dioxide. It turns out that the main source of life on Earth is carbon dioxide. It seems that the longevity of Caucasians is associated with less oxygen at altitude. The oxygen content in the modern atmosphere is 21% at sea level, and in the mountains - 15% at a level of 3-4 kilometers. Buteyko writes that 10-15% oxygen in the atmosphere is optimal for our cells. We sing the glory to the wrong one.

Another fact in favor of carbon dioxide is associated with its historical loss in the atmosphere. In biblical times, people lived much longer, the Bible testifies to this. The lifespan then exceeded 900.

So, carbon dioxide is not poison for us, but the most valuable source of life. But a large excess of carbon dioxide is harmful, like an excess of any other substance. Everything needs a norm. However, if you slightly increase the carbon dioxide content in the inhaled air, you get an interesting phenomenon: the immune system becomes stronger, super endurance develops, nervous system is restored, illnesses go away.

Buteyko continues:
- “Back in the forties of the 20th century, Holden established that the body regulates CO2 levels with an accuracy of 0.1% (“CO2 regulation threshold”). Since the dosage is carried out with such precision, it means carbon dioxide is very important for our body. For comparison, only when oxygen decreases by 5% in the lungs does the body begin to equalize it. But the body does not react in any way to an increase in oxygen, since it has never encountered such an anomaly in its historical path.

Our body can heal itself. Many symptoms of diseases are the activation of this mechanism. The simplest example is an increase in body temperature during a cold. Buteyko examines how our body protects itself from deep breathing and from the loss of carbon dioxide in the body:

1. Spasms- narrowing of the valves, release of carbon dioxide.
2. Reduced pressure. From deep breathing, after 1-3 minutes, hypotension develops, pressure drops, collapse is created, and shock occurs.
3. Increased cholesterol production regardless of diet. Cholesterol is a biological product with insulating properties. It isolates nerve fibers, cells, vascular membranes from various influences, protects the body from loss of carbon dioxide. Quite often, cholesterol is deposited on the eyelids (yellow spots, plaques). Until now, they were removed surgically, because they themselves never disappeared, they only grew larger. And in the process of decreasing breathing, these plaques dissolved before our eyes within 2-3 weeks! A similar process occurs in blood vessels. This process is definitely reversible.
4. With the loss of CO2, mucous secretion increases, cell permeability increases, this leads to edema, the appearance of bags under the eyes, puffiness of the face, chronic runny nose, sputum production, and increased secretion in the stomach. All mucous membranes begin to leak their “secrets”. From this it is clear that sputum is useful for asthmatics and pulmonary patients. It cannot be coughed up because it protects the lungs from the release of carbon dioxide.
5. Hyperthyroidism(which enhances metabolism) can also develop from deep breathing.
6. Sclerosis of blood vessels, bronchi and lungs is a protective reaction against the release of carbon dioxide. Sclerosis is a thickening of tissue that protects it from a toxic external environment. This is its role, its biological meaning.

Here short list defensive reactions body from loss of CO2. Having crossed some of their norms, they become a reaction of damage; create their own symptoms of deep breathing and illness. Spasm of the bronchi or blood vessels reduces the flow of oxygen to the tissues and causes oxygen starvation. This is the true action of deep breathing.

The deeper the breathing, the less oxygen enters the tissues of the brain, heart and kidneys due to spasm of blood vessels and bronchi.

Spasm of the bronchi and blood vessels occurs to reduce the release of carbon dioxide, but oxygen moves through the same channel! Consequently, the oxygen flow automatically decreases. Therefore, deep breathers suffer doubly - they have neither carbon dioxide nor oxygen! These two substances have completely different effects. Carbon dioxide is the source of life and a regenerator of body function, and oxygen is an energy source.

Deep breathing reduces the carbon dioxide content in the body and reduces the oxygen content. Therefore, the shallower the depth of breathing, the more oxygen enters the body. This law is well reflected in the doctoral dissertation of Igor Aleksandrovich Kovalenko, defended in 1967 at the Parin Institute. He shows these dependencies using the example of animals. By the way, this work has disappeared from the university library, but you can read the abstract, says Buteyko.

And he continues:
- Due to deep breathing, many painful processes are formed that had neither theoretical justification nor practical treatment! Unfortunately, and this is recognized by many prominent doctors, medicine has now reached a dead end for many diseases. . . In fact, nothing can cure! - this is a doctor, a doctor says - asthma is incurable - this is what they say to the patient right in the face! Hypertension is practically incurable, stomach ulcers are incurable, eczema is forever, even chronic runny nose cannot be cured. All these incurable diseases arise from deep breathing. And the patient is taught to breathe even deeper, aggravating the disease. If the depth of breathing is reduced, then an attack of asthma or chronic runny nose can end at the same moment, because the reactions that I spoke about occur within 3-5 minutes, and improvement begins within 10-20 seconds. These are instant reactions.
In the cold, warming up your hands and nose is easy - reduce your breathing. The blood vessels will expand and you will immediately warm up! You are scared, excited, nervous trembling hits you - slow down your breathing and calm down will come in 1-2 minutes. By understanding these mechanisms, you can control your own body!
Insomnia occurs in those who inhale deeply before going to bed, due to various reasons. By slowing down your breathing, you can easily and calmly fall asleep in a matter of minutes. Why is it so simple? Breathing is the main function of the body, a change in which within 20-30 seconds affects the entire body, all organs and systems.
Not all diseases are caused by deep breathing. A problem arose - to check what proportion of patients with asthma, hypertension and angina pectoris suffer from deep breathing. As it turned out later, 95%! How can you say that the patient was sick from deep breathing? He was cured, which means he was sick from deep breathing.
What is the principle of preventing and treating deep breathing diseases? Do not let carbon dioxide in the body decrease, keep it at a level. Decreased - raise to normal. This will prevent and cure the disease!!!

So let's start with the basics. When a person breathes, it absorbs oxygen and releases carbon dioxide. Carbon dioxide is also released when hydrocarbons are burned. The average level of CO₂ on our planet is currently is about 400 PPM (Parts per million - parts per million, or 0.04%) and is constantly growing due to constant growth consumption of petroleum products. At the same time, it is worth knowing that trees absorb carbon dioxide and this is precisely their main function (and not, as they mistakenly believe, that they only produce oxygen).

While a person is outdoors, there are no problems, but they begin when he is indoors. If a person is locked in a sealed room without an influx of fresh air, then he will die not from a lack of oxygen, as most people mistakenly believe, but from a multiple excess of the level of carbon dioxide that this person himself produced in the lungs. Let's put aside the problems of ventilation of public transport (I will write about this separately) and turn our attention to city apartments/country houses, in which there is a massive lack of ventilation.

At the same time, a person spends at least a third of his life in his house/apartment, and in reality half of it - you cannot save on your own health!

2. The problem of high CO₂ content in the air is especially relevant in the cold season, because... In summer, almost everyone has their windows open all the time. And with the onset of cold weather, the windows are opened less and less often, ultimately reducing to occasional ventilation. And, what a coincidence, it is during the cold season that depression, drowsiness and loss of strength appear.

3. Previously, there was even such a tradition - to seal the cracks in the windows before the cold weather. Often, together with vents, they completely excluded the flow of fresh air into the house. I emphasize once again that Fresh air It is needed not because it contains the oxygen necessary for breathing, but in order to reduce the excess carbon dioxide content by replacing the air in the room.

4. Many people think that they have a hood (in apartments, at least in the kitchen and bathroom), and the room will be ventilated through it. Yeah, in addition, installing plastic windows that are completely sealed. But how will the air go into the exhaust if you don’t have an inflow in the form of either cracks in the frames or an open window? And with good draft, it usually pulls air from the entrance.

5. The only thing worse is to install an air conditioner in the form of a split system and use it with the windows closed. Remember, when the air conditioner is running, DO NOT close the windows! Here is a modern airtight country house that has no gaps in the building envelope. And you don’t need to be fooled by stories that wood or aerated concrete “breathe” and therefore you can not give a damn about ventilation. Remember, this term refers to the high vapor permeability of the material, and not the ability to supply fresh street air into the house.

6. Most are limited to an exhaust fan from the bathroom and kitchen. Okay, the fan is turned on, all the windows and doors in the house are closed. What will be the result? That's right, there will be a vacuum in the house, because there is nowhere for new air to come from. For natural ventilation to work, fresh air must enter the house.

7. To measure the level of carbon dioxide in the air, relatively affordable sensors with an NDIR sensor have now appeared. Non-dispersive infrared (NDIR) is based on the change in infrared intensity before and after absorption in an infrared detector with selective sensitivity. Initially, I was going to buy such a sensor on Aliexpress last year (then it cost about $100), but the increased price due to the rise in the dollar exchange rate made me think and look for alternative options. Unexpectedly, this sensor was found in Russia under a Russian brand for the same $100 at last year’s exchange rate. In total, I found the best deal on Yandex.Market and purchased the sensor at a price of 3,500 rubles. The model is called MT8057. Of course, the sensor has an error, but it is not important when we're talking about that measurements with carbon dioxide concentrations exceeding several times the norm are important to us.

8. Closed plastic windows, air conditioners - all this is nonsense compared to the gas stove in the apartment (for the photo I lit a gas burner, because to photograph the stove it had to be washed).

9. So, all attention to the schedule. Kitchen 9 square meters, ceilings 3 meters high, opened door to the kitchen (!), closed window, there is a natural draft hood (in summer the draft is weak), one person. The sensor stands at a height of 1 meter from the floor, on the dining table. The “normal” CO₂ level in a room without people is about 600 PPM. One person comes and the CO₂ level immediately rises. Leaves - falls. It comes again - it rises again. And after that he turns on one (!) gas burner. CO₂ levels rise above 2000 PPM almost instantly. Anxiety! We open the window. We observe how the concentration of carbon dioxide in the air slowly decreases. And add 1-2 more people here. Even if you don’t turn on the gas stove, then 3 adults without doing heavy work physical work raise the CO₂ level in the room to a critical level in 30 minutes.

Do you cook on a gas stove? Be sure to open the window and turn on the hood (do both at the same time).

Have you turned on the air conditioner? Be sure to open the window.

Are you just in the room? Be sure to open the window. And if there are many people in the room, open the window.

And at night, while sleeping, the window must be kept open.

In short, you either have to have a supply vent or a window that is always open.

10. Regarding trees and how they can be useful. Their most important function during growth - absorption of carbon dioxide. Few people think about why wood burns and where so much energy comes from. So this energy in the form of carbon accumulates in the tree trunk as a result of the absorption of carbon dioxide. Trees produce oxygen as a by-product of the photosynthesis reaction.

11. Opening a window in the warm season is not difficult and, in general, in summer the problem is not so pressing (except for cases of using air conditioners with closed windows). Problems begin in winter, because no one keeps the window open all the time, this means huge uncontrollable heat losses and it will be simply cold. It is precisely at this moment that the alarm should be raised. Health is priceless.

The problem is very serious and global in nature. For example, until last fall I didn’t think at all about the importance of ventilation for health: what’s in the apartment, what’s in country house. If you look into the past, it is precisely the regular autumn depression, drowsiness and Bad mood During the cold season of the year in a city apartment, they encouraged me to think in the direction of the need to leave the city, so to speak, and build, because... In the fall and winter, I had a headache and general weakness of the body when I was in the city. But as soon as I went out into nature, the problem disappeared. I chalked it all up to a lack of sunlight, but that wasn’t the issue. In winter, I stopped keeping the window open (it was cold) and the CO₂ in the apartment was many times higher.

The simplest and most affordable solution to the problem is to constantly keep the window open, or ventilate based on the readings from the CO₂ sensor. A normal level of CO₂ in a room can be considered a concentration of up to 1000 PPM; if higher, it is necessary to urgently ventilate. Humidity can be considered an indirect indicator of high concentrations of carbon dioxide in the air. If, without objective reasons and a decrease in temperature in the room, the humidity begins to rise, this means that the CO₂ level is increasing.

The danger of increased concentrations of carbon dioxide in the air is that the human body reacts with a very long delay. By the time you felt that the room was stuffy and needed to be ventilated, you had already been in a room with a high CO₂ content in the air for at least half an hour.

In the next post I will talk about what problems there are with ventilation in public transport (buses, trains, planes). I’ll also show you how to properly organize ventilation in a country house, which everyone somehow forgets about.

To be continued.

Articles on the topic for self-study.