15.09.2015 14:44
“People began to live well, they began to install double-glazed windows, hoods, armored doors on rubber layers. And they don’t even realize that all this can lead to tragedy, ”Igor Zlobin, the head of the Sevastopol chimney and furnace detachment, told how to protect yourself from carbon monoxide poisoning.
All these conveniences individually are harmless and do not pose a danger to humans. But when using electric fans in bathrooms or electric hoods in kitchens with closed windows in conjunction with working geysers and boilers there is a potential danger to health and life. There was a long period in Sevastopol when, due to misuse gas equipment two people died every year.
Before installing a geyser or boiler in an apartment, the special services of Gorgaz conduct a briefing, to which people, as a rule, are superficial. “It can happen to anyone, but not to me,” they think.
Why can a boiler with a column be dangerous?
“An apartment is like a vessel with air,” explains Igor Evgenievich. - If all windows and doors are closed and the hood is working, where does the air come from, which this same hood pulled out of the apartment? Thrust in the flue and ventilation ducts“Tips over”, changes direction, and all channels begin to supply air from the street to the apartment. And if a column or boiler works nearby, carbon monoxide begins to enter the apartment along with the street air.
Carbon monoxide is colorless, odorless, and the primary symptoms of carbon monoxide poisoning are similar to food poisoning. The first dose of poisoning is usually given to pets and small children.
“A few years ago we had poisoning,” says the head. The child and the father are dead. The reason is that the gas boiler, the exhaust hood were turned on and all the windows were closed. At first, the cat became ill, he began to feel sick. The animal was kicked out onto the balcony without even thinking that these were symptoms of carbon monoxide poisoning. The child felt the second poisoning. He breathed this gas, received a critical dose and fell, losing consciousness.
A person can detect only the mildest stage of poisoning in himself - general malaise, dizziness, nausea. The poisoned person cannot determine the next stages and their signs - the brain loses its normal working capacity, becomes intoxicated, and the person ceases to adequately perceive what is happening - he feels bad, but he does not guess to turn off the gas appliance and open the window.
“There was another case: two young people came from Kherson and rented an apartment. We stopped in the evening and decided to take a bath. The result is two corpses. We go in - the gas column is working, the windows are closed. A young girl is lying in the hallway and a guy is in the bathroom. The elderly owner of the apartment cries: “I told them, open the window!” And in the kitchen - the rules for using the column are written in huge letters, ”said Igor Evgenievich.
Carbon monoxide quietly and imperceptibly kills a person: literally 10-15 minutes with its two percent content in an apartment is a lethal dose.
“Several years ago in a house on the street. Kievskaya was found the corpse of a young guy. The cause of death was a lethal dose of carbon monoxide in the blood. The apartment has double-glazed windows, dense, rubberized metal Entrance door, when you turn on the light in the bathroom, the fan built into the duct turns on, sucking air out of the room. We conducted an investigative experiment in the apartment, repeating the conditions of what happened. At closed doors and windows, working ventilation in the bathroom, the draft in the smoke and ventilation ducts disappeared. The experiment showed that while using the gas column, the window in the kitchen was closed. This violation led to the death of the guy. By the way, he died already in the hospital, when they brought him, it turned out that they didn’t even have syringes, and, in general, the doctors don’t know why he feels bad. Help not provided in time, the result is the death of a person. And everything happened like this: the guy went to wash, turned on the light and, accordingly, ventilation. In less than ten minutes, the draft in the channels of the apartment changed direction, carbon monoxide went into the apartment. After washing, the guy went to bed and never woke up again.
To avoid such cases, you need to perform several simple rules:
1. Every day, before using the boiler and dispenser, it is necessary to check the draft in the flue and ventilation ducts.
This can be done by bringing a piece of paper to the ventilation grill, a match fire under the smoke extractor cap of a gas appliance or opening an ash pan - a technological hatch with a door for checking draft, which is located under the chimney and should be in every boiler. V normal conditions it should always be closed.
If a sheet of paper sticks to the ventilation grill, and the flame of the match deviates towards the channel, then there is a draft.
Please note: draft in apartments is much worse in summer than in winter.
2. During the operation of the boiler or column, be sure to open the window for at least 2-3 fingers: for them normal operation there must be airflow. In an apartment with tight closed windows There is simply nowhere for air to come from. And if the window is open, there will be no danger.
3. Do not turn on the hood, ventilation at the same time as the boiler or column is running.
The electric fan in the bathroom works on the same principle as the hood: it also sucks air out of the apartment.
4. You can use the gas column for no more than half an hour. After - turn off the equipment for twenty minutes and turn it on again for half an hour if necessary.
“If a person fulfills all these requirements, then nothing health threatening will not happen even with old geysers, which are almost 50 years old, ”says Igor Evgenievich.
“In Sevastopol, not a single fatal poisoning was recorded in an apartment where a window was open at the time the gas column or boiler was used,” the specialist shares. “This is a very important condition.”
Do not rely on the automation of modern gas appliances: it does not recognize carbon monoxide, but reacts to changes in the temperature of the fumes returning back. And if it is cool outside, the mixture of carbon monoxide with outdoor air remains cool and the sensors do not detect an increase in temperature and do not turn off the gas appliance. The apartment begins to be saturated with carbon monoxide.
“Many people say: “Why then the boiler, if you open the window in the cold?” But it's supposed to be, it's your guarantee against an accident.
The air for burning natural gas comes from nowhere other than a window. Carbon monoxide is an element of underburning, that is, natural gas in a gas appliance does not burn properly. When natural gas burns normally, combustion products harmless to humans are released into the chimney - carbon dioxide and water vapor. But if there is not enough oxygen in the room, natural gas begins to burn incorrectly, releasing soot and carbon monoxide, which is very dangerous for life.
There were cases when people came into the apartment, wanting to help, began to pump out the victim without opening the window and also fell, breathing heavily, ”says Igor Evgenievich.
Why check traction?
It happens that pigeons and rats get into the canal, fallen leaves, a package can fly in. It is quite possible that today the stove service checked the draft in your apartment and found that everything is working fine, and tomorrow a foreign object will fall into the chimney. This is all very serious: “There was a case when a rat made a nest in a warm place and completely clogged the chimney. People from this only slightly poisoned, and, fortunately, no one, except for the rat, was seriously injured. And if they had checked the draft before turning on the gas appliance, nothing would have happened.
Igor Evgenievich said that he had recently appeared new type gas equipment - turbocharged. This gas appliances equipped closed camera combustion are modern and safe: all combustion products go outside through a pipe passing through outer wall Houses. Such equipment is usually installed in new homes. “When using it, you can turn on the hood, ventilation, and not open the window at the same time,” the specialist summed up.
- UN hazard class 2.3
- UN secondary hazard 2.1
The structure of the molecule
The CO molecule, like the isoelectronic nitrogen molecule, has a triple bond. Since these molecules are similar in structure, their properties are also similar - very low melting and boiling points, close values of standard entropies, etc.
Within the framework of the method of valence bonds, the structure of the CO molecule can be described by the formula: C≡O:, and the third bond is formed according to the donor-acceptor mechanism, where carbon is an electron pair acceptor, and oxygen is a donor.
Due to the presence of a triple bond, the CO molecule is very strong (the dissociation energy is 1069 kJ / mol, or 256 kcal / mol, which is more than that of any other diatomic molecules) and has a small internuclear distance (d C≡O = 0.1128 nm or 1, 13Å).
The molecule is weakly polarized electric moment its dipole μ = 0.04 10 -29 C m (direction of the dipole moment O - →C +). Ionization potential 14.0 V, force coupling constant k = 18.6.
Discovery history
Carbon monoxide was first produced by French chemist Jacques de Lasson by heating zinc oxide with charcoal, but was initially mistaken for hydrogen because it burned with a blue flame. The fact that this gas contains carbon and oxygen was discovered by the English chemist William Cruikshank. Carbon monoxide outside the Earth's atmosphere was first discovered by the Belgian scientist M. Mizhot (M. Migeotte) in 1949 by the presence of the main vibrational-rotational band in the IR spectrum of the Sun.
Carbon monoxide in the Earth's atmosphere
There are natural and anthropogenic sources of entry into the Earth's atmosphere. V vivo, at the Earth's surface, CO is produced by incomplete anaerobic decomposition organic compounds and during the combustion of biomass, mainly during forest and steppe fires. Carbon monoxide is formed in the soil both biologically (excreted by living organisms) and non-biologically. The release of carbon monoxide due to phenolic compounds common in soils containing OCH 3 or OH groups in ortho- or para-positions with respect to the first hydroxyl group has been experimentally proven.
The overall balance of production of non-biological CO and its oxidation by microorganisms depends on specific environmental conditions, primarily on humidity and the value of . For example, from arid soils, carbon monoxide is released directly into the atmosphere, thus creating local maxima in the concentration of this gas.
In the atmosphere, CO is the product of chain reactions involving methane and other hydrocarbons (primarily isoprene).
The main anthropogenic source of CO is currently the exhaust gases of internal combustion engines. Carbon monoxide is formed when hydrocarbon fuels are burned in internal combustion engines at insufficient temperatures or a poorly tuned air supply system (insufficient oxygen is supplied to oxidize CO to CO 2 ). In the past, a significant proportion of anthropogenic CO emissions into the atmosphere came from lighting gas used for indoor lighting in the 19th century. In composition, it approximately corresponded to water gas, that is, it contained up to 45% carbon monoxide. At present, in the utility sector, this gas has been replaced by much less toxic natural gas (lower representatives homologous series alkanes - propane, etc.)
The intake of CO from natural and anthropogenic sources is approximately the same.
Carbon monoxide in the atmosphere is in a rapid cycle: the average residence time is about 0.1 year, oxidized by hydroxyl to carbon dioxide.
Receipt
industrial way
2C + O 2 → 2CO (the thermal effect of this reaction is 22 kJ),
2. or when reducing carbon dioxide with hot coal:
CO 2 + C ↔ 2CO (ΔH=172 kJ, ΔS=176 J/K).
This reaction often occurs in the furnace furnace, when the furnace damper is closed too early (until the coals have completely burned out). The resulting carbon monoxide, due to its toxicity, causes physiological disorders ("burnout") and even death (see below), hence one of the trivial names - "carbon monoxide". The picture of the reactions taking place in the furnace is shown in the diagram.
The carbon dioxide reduction reaction is reversible, the effect of temperature on the equilibrium state of this reaction is shown in the graph. The flow of the reaction to the right provides the entropy factor, and to the left - the enthalpy factor. At temperatures below 400°C, the equilibrium is almost completely shifted to the left, and at temperatures above 1000°C to the right (in the direction of CO formation). At low temperatures the rate of this reaction is very slow, so carbon monoxide is quite stable under normal conditions. This equilibrium has a special name boudoir balance.
3. Mixtures of carbon monoxide with other substances are obtained by passing air, water vapor, etc. through a layer of hot coke, hard or brown coal, etc. (see producer gas, water gas, mixed gas, synthesis gas).
laboratory method
TLV (maximum threshold concentration, USA): 25 MPC r.z. according to Hygienic Standards GN 2.2.5.1313-03 is 20 mg/m³
Protection against carbon monoxide
Due to such a good calorific value, CO is a component of various technical gas mixtures(see, for example, generator gas), used, among other things, for heating.
halogens. Greatest practical use received a reaction with chlorine:
CO + Cl 2 → COCl 2
The reaction is exothermic, its thermal effect is 113 kJ, in the presence of a catalyst (activated carbon) it proceeds already at room temperature. As a result of the reaction, phosgene is formed - a substance that has become widespread in various branches of chemistry (and also as a chemical warfare agent). By analogous reactions, COF 2 (carbonyl fluoride) and COBr 2 (carbonyl bromide) can be obtained. Carbonyl iodide was not received. The exothermicity of reactions rapidly decreases from F to I (for reactions with F 2, the thermal effect is 481 kJ, with Br 2 - 4 kJ). It is also possible to obtain mixed derivatives, such as COFCl (for details, see halogen derivatives of carbonic acid).
By the reaction of CO with F 2 , in addition to carbonyl fluoride, a peroxide compound (FCO) 2 O 2 can be obtained. Its characteristics: melting point -42°C, boiling point +16°C, has a characteristic odor (similar to the smell of ozone), decomposes with an explosion when heated above 200°C (reaction products CO 2 , O 2 and COF 2), in acidic medium reacts with potassium iodide according to the equation:
(FCO) 2 O 2 + 2KI → 2KF + I 2 + 2CO 2
Carbon monoxide reacts with chalcogens. With sulfur it forms carbon sulfide COS, the reaction proceeds when heated, according to the equation:
CO + S → COS ΔG° 298 = −229 kJ, ΔS° 298 = −134 J/K
Similar selenoxide COSe and telluroxide COTe have also been obtained.
Restores SO 2:
SO 2 + 2CO → 2CO 2 + S
With transition metals, it forms very volatile, combustible and toxic compounds - carbonyls, such as Cr (CO) 6, Ni (CO) 4, Mn 2 CO 10, Co 2 (CO) 9, etc.
As stated above, carbon monoxide is slightly soluble in water, but does not react with it. Also, it does not react with solutions of alkalis and acids. However, it reacts with alkali melts:
CO + KOH → HCOOK
An interesting reaction is the reaction of carbon monoxide with metallic potassium in an ammonia solution. In this case, the explosive compound potassium dioxodicarbonate is formed:
2K + 2CO → K + O - -C 2 -O - K +
Reaction with ammonia at high temperatures it is possible to obtain an important industrial compound - hydrogen cyanide HCN. The reaction proceeds in the presence of a catalyst (oxide
Signs that carbon monoxide (carbon monoxide (II), carbon monoxide, carbon monoxide) has formed in the air in dangerous concentrations are difficult to determine - invisible, may not smell, accumulates in the room gradually, imperceptibly. It is extremely dangerous for human life: it has a high toxicity, excessive content in the lungs leads to severe poisoning and deaths. Every year, a high death rate from gas poisoning is recorded. You can reduce the risk of poisoning by following simple rules and using special carbon monoxide sensors.
What is carbon monoxide
Natural gas is formed during the combustion of any biomass, in industry it is a combustion product of any carbon-based compounds. In both cases prerequisite outgassing is a lack of oxygen. Large volumes of it enter the atmosphere as a result of forest fires, in the form of exhaust gases produced during the combustion of fuel in car engines. For industrial purposes, it is used in the production of organic alcohol, sugar, processing of animal meat and fish. A small amount of monoxide is also produced by the cells of the human body.
Properties
From the point of view of chemistry, monoxide is an inorganic compound with a single oxygen atom in the molecule, chemical formula- SO. This Chemical substance, which does not have a characteristic color, taste and smell, it is lighter than air, but heavier than hydrogen, with room temperatures not active. A person who smells, feels only the presence of organic impurities in the air. Belongs to the category of toxic products, death at a concentration in the air of 0.1% occurs within one hour. The characteristic of the maximum permissible concentration is 20 mg / m3.
The effect of carbon monoxide on the human body
For humans, carbon monoxide is mortal danger. Its toxic effect is explained by the formation of carboxyhemoglobin in blood cells, the product of the addition of carbon monoxide (II) to blood hemoglobin. A high level of carboxyhemoglobin causes oxygen starvation, insufficient oxygen supply to the brain and other tissues of the body. With mild intoxication, its content in the blood is low, destruction naturally possibly within 4-6 hours. At high concentrations, only medical preparations.
Carbon monoxide poisoning
Carbon monoxide is one of the most dangerous substances. In case of poisoning, intoxication of the body occurs, accompanied by deterioration general condition person. It is very important to recognize the signs of carbon monoxide poisoning early. The result of treatment depends on the level of the substance in the body and on how soon help arrived. In this case, minutes count - the victim can either recover completely or remain sick forever (it all depends on the speed of the rescuers' response).
Symptoms
Depending on the degree of poisoning, headaches, dizziness, tinnitus, heart palpitations, nausea, shortness of breath, flickering in the eyes, general weakness can be observed. Drowsiness is often observed, which is especially dangerous when a person is in a gassed room. In case of inhalation a large number toxic substances, convulsions, loss of consciousness are observed, in especially severe cases - coma.
First aid for carbon monoxide poisoning
First aid should be provided to the victim on the spot in case of carbon monoxide poisoning. We must immediately move it to Fresh air and call a doctor. You should also remember about your safety: you need to enter a room with a source of this substance only by taking a deep breath, do not breathe inside. Until the doctor arrives, it is necessary to facilitate the access of oxygen to the lungs: unfasten buttons, remove or loosen clothes. If the victim has lost consciousness and stopped breathing, artificial ventilation of the lungs is necessary.
Antidote for poisoning
A special antidote (antidote) for carbon monoxide poisoning is a drug that actively prevents the formation of carboxyhemoglobin. The action of the antidote leads to a decrease in the body's need for oxygen, support for organs that are sensitive to a lack of oxygen: the brain, liver, etc. It is administered intramuscularly at a dosage of 1 ml immediately after the patient is removed from the area with a high concentration of toxic substances. You can re-enter the antidote no earlier than an hour after the first injection. It can be used for prevention.
Treatment
In the case of mild exposure to carbon monoxide, treatment is carried out on an outpatient basis, in severe cases, the patient is hospitalized. Already in the ambulance, he is given an oxygen bag or mask. In severe cases, in order to give the body a large dose of oxygen, the patient is placed in a pressure chamber. An antidote is administered intramuscularly. The level of gas in the blood is constantly monitored. Further rehabilitation is medical, the actions of doctors are aimed at restoring the functioning of the brain, of cardio-vascular system, lungs.
Consequences
Exposure to carbon monoxide on the body can cause serious diseases: brain performance, behavior, human consciousness change, inexplicable headaches appear. Especially the influence harmful substances memory is the part of the brain that is responsible for the transition of short-term memory into long-term memory. The patient may feel the consequences of carbon monoxide poisoning only after a few weeks. Most victims fully recover after a period of rehabilitation, but some feel the consequences for a lifetime.
How to detect carbon monoxide in a room
Carbon monoxide poisoning is easy at home, and it doesn't just happen during a fire. The concentration of carbon monoxide is formed when careless handling with a stove damper, when operating a faulty geyser or ventilation. A gas stove can be a source of carbon monoxide. If there is smoke in the room, this is already a reason to sound the alarm. For constant monitoring of the gas level, there are special sensors. They monitor the level of gas concentration and report the excess of the norm. The presence of such a device reduces the risk of poisoning.
Video
What we call carbon monoxide is the result of the most different types combustion - from a conventional gas burner to car exhaust gases. At the same time, this gas does not give out its presence in the surrounding space either by smell or color, which makes it especially dangerous. You will not notice any changes in the house until the state of health begins to give alarm signals.
Don't forget to open the fireplace damper
Cozy in the house - a wonderful remedy for both dampness and cold. But fireplaces and stove heating are also an increased source of carbon monoxide in the room. A sign of the absence of carbon monoxide in the stove will be an even bluish flame, but if the wood in the fireplace began to smoke, a reddish tint appeared - this indicates the appearance of carbon monoxide.
It is often a mistake to close the damper prematurely. Assuming that the fuel is completely burned out, stove owners often close the chimney damper to save heat. Smoldering coals with a lack of air form carbon monoxide, which enters the room through leaky areas furnace design. If there are a few unburned firebrands left in the firebox or stove, it is better to extinguish them or give them time to burn out completely. When the coals darken and there are no flames above them, after ten minutes the valve can be closed. Finish the operation of the fireplace or stove furnace should be 2 hours before bedtime.
Use electric heaters in rooms more carefully
Even an ordinary electric heater can be a serious test for health. It would seem that they turned on to warm up for only a couple of hours, what could be dangerous here? testing regularly various models electric heaters, and the results make you think before turning on such a device for a long time. For example, already after half an hour of operation of the spiral heater, the humidity in the room is reduced by 3%, and the oxygen content in the air by 3%. And if such heating works longer in the room, for example, from evening to morning, or all day, then after a few hours people may become ill. This type of heater, if it can be used, is only for a short time.
Ceramic Electric Heater Shown top scores- in half an hour of its operation, the humidity in the room fell by only 1%, and the oxygen concentration by 0.1%, such a device can be used for 3-4 hours, but then you still need to ventilate the room.
Grilling indoors is a risk factor
Modern equipment for allows you to install a grill indoors, but you should not be limited to this. If used in the kitchen open fire, be sure to combine the grill with a powerful exhaust system. Carbon monoxide must be quickly removed through the ventilation system from the room so that it does not spread from the kitchen to other rooms.
Avoid using a gas stove or oven for heating
Warm up the apartment a little with the help of the usual gas stove seems like a simple and cheap option. But, unfortunately, this is what very often leads to carbon monoxide poisoning. Very little heat is released from the gas burner, it will take a long time to keep the fire on. With poor access to oxygen closed kitchen incomplete combustion occurs, resulting in the formation of CO from carbon compounds contained in natural gas.
Use proven heating systems
Any heating system in the house requires preparation for the long cold season. The efficiency of heating the house and the favorable atmosphere in the rooms depend on good draft in the system. If the chimney is dirty, foreign objects got into it, cracks and destruction appeared in the masonry - all this leads to a violation of traction. Gas combustion products enter the house and poison you with carbon monoxide. Any deterioration in the weather - freezing of the heads, strong wind or fog can become additional factors and reduce the level of draft in the chimney to critically low.
Air CO level sensor
An indispensable assistant keeping the air in your home clean, especially if you use a fireplace, grill, or furnace heating, will become a simple device - a carbon monoxide level sensor in the air. Such a device constantly monitors the level of CO in the air and will give an alarm at any time of the day if the concentration of carbon monoxide in your rooms is too high. In the event of a leak, carbon monoxide, which is lighter than air, rises to the ceiling of the room. Therefore, the carbon monoxide detector is installed in the upper part of the room. The device is installed 5-15 cm below the ceiling, at a distance of at least 1-2 m from a potential source of carbon monoxide.
Watch out for symptoms of carbon monoxide poisoning
Depending on how much time a person spent in a room with high level carbon monoxide, he may first feel tired, weak, and then dizzy. You should not wait for more serious symptoms; at the slightest discomfort, it is best to immediately ventilate the room and remove the source of carbon monoxide, for example, turn off the heater.
If measures are not taken, more serious manifestations of carbon monoxide poisoning may occur - nausea, redness of the skin, convulsions, up to loss of consciousness and coma. This is due to the inhibition of the respiratory center and the human cardiovascular system by carbon monoxide.
Very dangerous is still prolonged exposure to small doses of carbon monoxide, which can occur even on ordinary kitchen, in the process of cooking on a gas stove without ventilation. Pay attention to a headache, especially if it occurs simultaneously in several people in the room.
