High oxygen content in the air. The concentration of oxygen in water: is it soluble and how is it determined? Observation is
In our body, oxygen is responsible for the process of energy production. In our cells, only thanks to oxygen, oxygenation occurs - the conversion of nutrients (fats and lipids) into cell energy. With a decrease in the partial pressure (content) of oxygen in the inhaled level - its level in the blood decreases - the activity of the organism at the cellular level decreases. It is known that more than 20% of oxygen is consumed by the brain. Oxygen deficiency contributes Accordingly, when the level of oxygen falls, well-being, performance, general tone, and immunity suffer.
It is also important to know that it is oxygen that can remove toxins from the body.
Please note that in all foreign films, in case of an accident or a person in serious condition, first of all, emergency doctors put the victim on an oxygen apparatus in order to increase the body's resistance and increase its chances of survival.
The therapeutic effect of oxygen has been known and used in medicine since the end of the 18th century. In the USSR, the active use of oxygen for preventive purposes began in the 60s of the last century.
hypoxia
Hypoxia or oxygen starvation is a reduced oxygen content in the body or individual organs and tissues. Hypoxia occurs when there is a lack of oxygen in the inhaled air and in the blood, in violation of the biochemical processes of tissue respiration. Due to hypoxia, irreversible changes develop in vital organs. The most sensitive to oxygen deficiency are the central nervous system, heart muscle, kidney tissue, and liver.
The manifestations of hypoxia are respiratory failure, shortness of breath; violation of the functions of organs and systems.
The harm of oxygen
Sometimes you can hear that "Oxygen is an oxidizing agent that accelerates the aging of the body."
Here the wrong conclusion is drawn from the right premise. Yes, oxygen is an oxidizing agent. Only thanks to him, the nutrients from food are processed into energy in the body.
The fear of oxygen is associated with two of its exceptional properties: free radicals and poisoning with excess pressure.
1. What are free radicals?
Some of the huge number of constantly flowing oxidative (energy-producing) and reduction reactions of the body are not completed to the end, and then substances are formed with unstable molecules that have unpaired electrons on the outer electronic levels, called "free radicals". They seek to capture the missing electron from any other molecule. This molecule becomes a free radical and steals an electron from the next one, and so on.
Why is this needed? A certain amount of free radicals, or oxidants, is vital for the body. First of all - to combat harmful microorganisms. Free radicals are used by the immune system as "projectiles" against "invaders". Normally, in the human body, 5% of the substances formed during chemical reactions become free radicals.
The main reasons for the violation of the natural biochemical balance and the increase in the number of free radicals, scientists call emotional stress, heavy physical exertion, injuries and exhaustion against the background of air pollution, eating canned and technologically improperly processed foods, vegetables and fruits grown with the help of herbicides and pesticides, ultraviolet and radiation exposure.
Thus, aging is a biological process of slowing down cell division, and free radicals mistakenly associated with aging are natural and necessary defense mechanisms for the body, and their harmful effects are associated with a violation of natural processes in the body by negative environmental factors and stress.
2. "Oxygen is easy to poison."
Indeed, excess oxygen is dangerous. Excess oxygen causes an increase in the amount of oxidized hemoglobin in the blood and a decrease in the amount of reduced hemoglobin. And, since it is the reduced hemoglobin that removes carbon dioxide, its retention in the tissues leads to hypercapnia - CO2 poisoning.
With an excess of oxygen, the number of free radical metabolites grows, those very terrible “free radicals” that are highly active, acting as oxidizing agents that can damage the biological membranes of cells.
Terrible, right? I immediately want to stop breathing. Fortunately, in order to be poisoned by oxygen, an increased oxygen pressure is necessary, as, for example, in a pressure chamber (during oxygen barotherapy) or when diving with special breathing mixtures. In ordinary life, such situations do not occur.
3. “There is little oxygen in the mountains, but there are many centenarians! Those. oxygen is bad."
Indeed, in the Soviet Union in the mountainous regions of the Caucasus and in Transcaucasia, a certain number of long-livers were registered. If you look at the list of verified (i.e. confirmed) centenarians of the world throughout its history, the picture will not be so obvious: the oldest centenarians registered in France, the USA and Japan did not live in the mountains ..
In Japan, where the oldest woman on the planet Misao Okawa still lives and lives, who is already more than 116 years old, there is also the “island of centenarians” Okinawa. The average life expectancy here for men is 88 years, for women - 92; this is higher than in the rest of Japan by 10-15 years. The island has collected data on more than seven hundred local centenarians over a hundred years old. They say that: "Unlike the Caucasian highlanders, the Hunzakuts of Northern Pakistan and other peoples who boast of their longevity, all Okinawan births since 1879 are documented in the Japanese family register - koseki." The Okinhua people themselves believe that the secret to their longevity rests on four pillars: diet, active lifestyle, self-sufficiency and spirituality. Locals never overeat, adhering to the principle of "hari hachi bu" - eight tenths full. These "eight tenths" of them consist of pork, seaweed and tofu, vegetables, daikon and local bitter cucumber. The oldest Okinawans do not sit idle: they actively work on the land, and their recreation is also active: most of all they love to play a local variety of croquet.: Okinawa is called the happiest island - there is no hurry and stress inherent in the large islands of Japan. The locals are committed to the philosophy of yuimaru - "kindhearted and friendly collaborative effort".
Interestingly, as soon as the Okinawans move to other parts of the country, there are no long-livers among such people. Thus, scientists studying this phenomenon found that the genetic factor does not play a role in the longevity of the islanders. And we, for our part, consider it extremely important that the Okinawa Islands are located in an actively windswept zone in the ocean, and the level of oxygen content in such zones is recorded as the highest - 21.9 - 22% oxygen.
Therefore, the task of the OxyHaus system is not so much to INCREASE the level of oxygen in the room, but to RESTORE its natural balance.
In the tissues of the body saturated with a natural level of oxygen, the metabolic process is accelerated, the body is “activated”, its resistance to negative factors increases, its endurance and the efficiency of organs and systems increase.
Technology
Atmung oxygen concentrators use NASA's PSA (Pressure Variable Absorption) technology. Outside air is purified through a filter system, after which the device releases oxygen using a molecular sieve from the volcanic mineral zeolite. Pure, almost 100% oxygen is supplied by a stream at a pressure of 5-10 liters per minute. This pressure is sufficient to provide the natural level of oxygen in a room up to 30 meters.
Air purity
“But the air is dirty outside, and oxygen carries all substances with it.”
That is why OxyHaus systems have a three-stage incoming air filtration system. And already purified air enters the zeolite molecular sieve, in which air oxygen is separated.
Danger/Safety
“Why is the use of the OxyHaus system dangerous? After all, oxygen is explosive.
The use of the concentrator is safe. There is a risk of explosion in industrial oxygen cylinders because the oxygen is under high pressure. The Atmung Oxygen Concentrators that the system is based on are free from combustible materials and use NASA's PSA (Pressure Variable Adsorption Process) technology, which is safe and easy to operate.
Efficiency
Why do I need your system? I can reduce the level of CO2 in the room by opening the window and ventilating.”
Indeed, regular ventilation is a very good habit and we also recommend it to reduce CO2 levels. However, city air cannot be called truly fresh - in addition to the increased level of harmful substances, the level of oxygen is reduced in it. In the forest, the oxygen content is about 22%, and in urban air - 20.5 - 20.8%. This seemingly insignificant difference significantly affects the human body.
“I tried breathing oxygen and didn’t feel anything”
The effect of oxygen should not be compared with the effect of energy drinks. The positive effect of oxygen has a cumulative effect, so the oxygen balance of the body must be replenished regularly. We recommend turning on the OxyHaus system at night and for 3-4 hours a day during physical or intellectual activities. It is not necessary to use the system 24 hours a day.
"What's the difference with air purifiers?"
The air purifier only performs the function of reducing the amount of dust, but does not solve the problem of balancing the oxygen level of stuffiness.
“What is the most favorable concentration of oxygen in a room?”
The most favorable oxygen content is close to the same as in the forest or on the seashore: 22%. Even if your oxygen level is slightly above 21% due to natural ventilation, this is a favorable atmosphere.
"Is it possible to be poisoned by oxygen?"
Oxygen poisoning, hyperoxia, occurs as a result of breathing oxygen-containing gas mixtures (air, nitrox) at elevated pressure. Oxygen poisoning can occur when using oxygen devices, regenerative devices, when using artificial gas mixtures for breathing, during oxygen recompression, and also due to excess therapeutic doses in the process of oxygen barotherapy. In case of oxygen poisoning, dysfunctions of the central nervous system, respiratory and circulatory organs develop.
Inertialization. Limiting oxygen concentration (PCC).
It is known that there is a limit for the content of flammable components under atmospheric conditions, this limit is called the lower explosive limit (LEL). If the concentration of flammable components in the air is below the LEL, we are protected from the risk of fire: the mixture is not flammable.
This is true for mixtures containing air. But there is another limit that affects flammability - a decrease in oxygen concentration.
This is the process of inertialization. Typical inert gases are nitrogen, argon, carbon dioxide and even water vapour. When the volume is filled with one of these gases, the oxygen concentration decreases.
What limit must the oxygen concentration not exceed in order for the process to remain safe, even if the concentration of combustible components is significantly higher than their LEL? This concentration is called the limiting oxygen concentration, or CCL.
For a rough estimate, consider the reaction scheme of a flammable substance. For example, for methane, it will look like this: CH 4 + 2 O 2 \u003d=> CO 2 + 2 H 2 O. In other words: for the oxidation (combustion) of one methane molecule, we need two oxygen molecules. Therefore, for oxygen, the stoichiometric coefficient s is equal to 2.
Now, to get the LEL value, we multiply the LEL value (5 vol.%) of methane by this factor: LEL = s?LEL = 2?5 = 10 vol. %.
Reducing the oxygen concentration to a level of less than 10 vol. % (with a safety margin of at least 2 vol.%) ensures process safety during inertialization.
Of course, for other substances we will have other values, for example, for octane (LEL = 0.8 vol.%) C 8 H 2 0 + 13 O 2 ==> 8 CO 2 + 10 H 2 O, stoichiometric coefficient s = 13, hence PCC = 13×0.8 = 10.4 vol. %.
For hydrogen (LEL = 4 vol. %, H 2 + ? O 2 ==> H 2 O) s = ?, hence the PCC is ?? 4 = 2 vol. %.
Keep in mind that these calculations are only a rough estimate, which seems to have a margin of safety (bottom) compared to the official values published by the German Chemical Industry Trade Union (see table). These data on the PCC were not obtained by calculations, but experimentally. Even the values for different inert gases differ here (which was not taken into account in the rough estimate).
The POC is the maximum oxygen concentration that must never be exceeded during inertialization. It is strongly recommended to take into account a safety margin of about 4 vol. %. When monitoring oxygen concentration in processes using hydrocarbons, a typical threshold is 6 vol. % O 2 to turn on the nitrogen supply, 4 vol. % O 2 to turn off the nitrogen supply and 7 vol. % O 2 to disable the process (main alarm). An interesting fact is that for the correct operation of the thermal catalytic sensor, an oxygen level exceeding the PCC is required.
Carbon dioxide mixture of acetone vapor in air
Solution: According to Table 3 of the application, we find the heat of formation of acetone 248.1∙10 3 J/mol. From the chemical formula of acetone (C 3 H 6 O) it follows that m c \u003d 3, m n \u003d 6, m 0 \u003d 1. The value of the remaining parameters is selected from Table 2 for carbon dioxide:
φph= 100∙0,735∙10 5 ∙248,1∙10 3 +0,584+1,292∙3+0,427∙6+0,570∙1 =48,1%
2,020-1+4,642∙3+1,160∙6-2,321∙1
φ О2 = =10.7; φ О2 without =1.2∙10.7-4.2=8.6%.
Therefore, when the oxygen concentration in a four-component system consisting of acetone vapor, carbon dioxide, nitrogen and oxygen is reduced to 8.6%, the mixture is explosion-proof. With an oxygen content of 10.7%, this mixture will be the explosive limit.
According to reference data, the MVSC of an acetone-air mixture when diluted with carbon dioxide is 14.9%. Let us define the relative calculation error:
Thus, the results of the calculation of the MWRC are underestimated by 28%
Control tasks
1. According to the maximum heat of combustion, determine how the lower concentration limit of ignition in air changes from the position of saturated hydrocarbons (ethane, propane, butane, pentane, propane, hexane) in the homologous series. Construct a graph of the dependence of the LEL on the molecular weight of the fuel.
2. Using the approximation formula, calculate how the concentration limits of fatty alcohols (methyl, ethyl, hexyl, octyl) change in the homologous series. Construct a graph of the dependence of the lower and upper flammable limits on the molecular weight of the fuel.
3. Determine the concentration limits of ignition of carbon disulfide at atmospheric pressure equal to 990 GPa, if its temperature limits are 223 + 299 K
5. Determine the concentration limits of ignition of a gas-vapor mixture consisting of 20% ethane, 60% ethylene and 20% ethyl alcohol vapor.
6. Determine the concentration limits of ignition in air of a vapor mixture consisting of 50% benzene, 35% toluene and 15% phenol, with an increase in temperature from 298 to 373K.
7. Determine whether an explosive concentration is formed when evaporating 15 kg of decanol in a room with a volume of 220 m 3, if the temperature is 310 K, the pressure is 1105 GPa?
8. Determine whether it is possible to form an explosive concentration at a temperature of 298 K above the surface of a liquid phase consisting of 25% acetic methyl ether, 40% acetic anhydride, 35% amyl alcohol?
9. Determine the composition of a two-component gas mixture consisting of ammonia and hydrogen sulfide vapors, if it is known that its lower concentration limit of ignition in air is 5.8%.
10. Determine the safe concentration of oxygen when diluting vapors of acetic propyl ether (∆H 0 𝒾 \u003d 513.7 ∙ 10 3 J / mol) in air with carbon dioxide, water vapor and nitrogen. Explain the reason for the different phlegmatizing efficiency of inert gases.
Application
to industrial safety requirements.
Production and consumption of air separation products
Types of dangers when working with air separation products
Hazards when handling liquid air separation products
Liquid air separation products have low temperatures, easily evaporate at normal temperatures, increasing their volume many times over.
Working with liquid air separation products involves the following hazards:
frostbite of service personnel;
rapid boiling with the creation of high pressures in closed vessels;
the possibility of destruction of structures made of carbon steel and other non-cold-resistant metals and materials.
Danger when working with oxygen
Air with a high volume fraction of oxygen (more than 23%) and pure oxygen are non-toxic and incapable of burning and exploding. But since oxygen is an active oxidizing agent, most substances and materials in an oxygen environment or in an air environment with a high oxygen content form systems with an increased explosion and fire hazard. The energy required to ignite materials in oxygen is many times less than the energy required to ignite in air under the same conditions. Therefore, the initiators of the ignition of many materials in an oxygen environment can be causes that are safe in other conditions: smoking, discharge of electricity, discharge of static electricity, heating of mechanical particles during friction, etc. Many materials that cannot burn in air, such as sheet steel, steel pipes, etc., burn in oxygen. The ability of materials to ignite increases with increasing pressure and temperature of oxygen.
Working with oxygen involves the following hazards:
ignition of clothing and hairline of service personnel who were in an environment of gaseous oxygen or air with a high oxygen content;
explosion of hydrocarbons and other explosive impurities when their content in liquid oxygen or liquid oxygen-enriched air exceeds the allowable limit;
an explosion during the impregnation of porous organic materials (asphalt, foam plastics, wood, etc.) with liquid oxygen, with the formation of oxyliquite explosives that are superior in sensitivity and power to conventional explosives.
If clothing ignites, immediately plunge into a bath of water or stand under an emergency shower. In the absence of water, clothing is immediately discarded or torn off the victim. Oxygen-impregnated clothing may burn for some time without air access, therefore it is not allowed to knock down the flame or wrap the burning one in a felt mat to stop air access.
Hazards when working with nitrogen and argon
Nitrogen and argon are inert gases, they are non-toxic, non-flammable and explosive. When working with these gases, the danger arises when their content in the air increases in the area where the maintenance and repair personnel are located. Replacing oxygen in the air and displacing oxygen from the body, they act on a person as suffocating agents (asphyxiants) due to a decrease in the partial pressure of oxygen.
In maintenance and repair areas where nitrogen and argon leaks are possible, shutdown of equipment and pipelines provided for by these Requirements, control of the oxygen content in the air of the working area and ventilation are carried out. The volume fraction of oxygen in the air of the working area is not less than 19%.
When the volume fraction of oxygen in the air is less than 19%, urgent measures are taken to eliminate leakages of inert gases, to ventilate and ventilate the premises and, if necessary, to stop work and evacuate personnel. In exceptional cases, short-term stay of people is allowed when the volume fraction of oxygen in the air is less than 16% with the obligatory use of hose and oxygen-insulating gas masks. It is not allowed to use filtering gas masks of all types for work in an environment with a low oxygen content.
With an oxygen content of 14 to 10%, human consciousness is not completely lost, but the perception of the environment changes, the sensitivity of the body (especially touch) is suppressed, coordination of movements is disturbed (loss of balance), working capacity progressively decreases (rapid fatigue occurs, feeling unwell).
With a further decrease in the oxygen content from 10 to 6%, muscle weakness appears (the ability to move is impaired), a feeling of indifference, “memory lapses” and loss of consciousness.
Signs of a decrease in the oxygen content in the victim's body are individual in nature and, in addition, depend on the volumetric oxygen content in the air and the time spent in the danger zone.
With a sharp decrease in the oxygen content in the atmosphere, and especially if a person accidentally enters an argon or nitrogen environment, a few breaths are enough to reduce the partial pressure of oxygen in the blood to a critical level - loss of consciousness always occurs suddenly and almost instantly.
There is no difference in the effect of argon or nitrogen on a person when they completely replace oxygen from the atmosphere.
|
Name of gas |
Cabinet painting |
Inscription text |
Lettering color |
Stripe color |
|
Nitrogen |
black |
Nitrogen |
yellow |
brown |
|
Argon technical |
black |
Argon technical |
blue |
blue |
|
Argon pure |
gray |
Argon pure |
green |
green |
|
Oxygen |
blue |
Oxygen oil hazardous |
black |
- |
Most often, people die in fires not from fire and high temperature, but because of a decrease in the concentration of oxygen in the air and poisoning by toxic combustion products.
The first symptoms of oxygen deficiency (increased breathing, reduced attention, impaired muscle coordination) are observed in humans when the oxygen content in the inhaled gas mixture is at the level of 16-17%. A decrease in the concentration of O 2 to 12-15% causes shortness of breath, increased heart rate, deterioration of mental activity, dizziness, fatigue. In cases where the concentration of O 2 decreases to 10-12%, consciousness is preserved, but nausea, severe fatigue appear, and breathing becomes intermittent. At a concentration of 8%, loss of consciousness quickly occurs, and below 6% - death within 6-8 minutes.
Toxic combustion products
This topic will be more fully revealed by specialists (Chemist, Toxicologist).
How dangerous toxic products of combustion are, the example of a fire that occurred in a clothing store in Tokyo (Japan) clearly shows. A fire broke out on the 3rd floor, and in a bar located on the 7th floor of the same building, 118 people died, 96 of them from poisoning with toxic combustion products, 22 people jumped out of windows. Many people passed out within the first 2-3 minutes; their death came in 4-5 minutes. after losing consciousness.
Smoke is dangerous not only because of the toxic substances it contains, but also because of reduced visibility. This makes it difficult, and sometimes almost impossible, to evacuate people from a dangerous room. To quickly get to a safe place, people must clearly see the emergency exits or their signs.
When visibility is lost, organized traffic (especially in an unfamiliar building, at objects with a massive presence of people) is disrupted, becomes chaotic, everyone moves in an arbitrarily chosen direction. There is panic. People are seized by fear, which suppresses consciousness, will. In this state, a person loses the ability to navigate, to correctly assess the situation.
Explosion
One of the types of instantaneous combustion is the explosion of special explosives, as well as mixtures of combustible gases, vapors or dust with air. These are chemical explosions.
Explosions of a physical nature are ruptures of various containers and apparatuses (boilers, reservoirs, cylinders, etc.) resulting from the development of excessive pressure by gases or vapors, exceeding the pressure that the walls of containers and apparatuses can withstand.
At the time of a chemical explosion, the substance burns at high speed, and the resulting gases and vapors expand greatly and create great pressure on the environment. This explains the enormous force of destruction caused by the explosion. An explosion usually creates a flame that can ignite nearby combustible substances.
Fire statistics
And their consequences
In the introduction to this manual, general statistics regarding fires have already been given. Tables 2 - 10 provide more detailed information reflecting the situation with fires in the Russian Federation for 2000-2002: the situation in cities and rural areas (including in relative units), the main causes of fires, the number of fires from children's pranks with fire, the age of the perpetrators of the fires that occurred, the types of burning objects, the causes of death in fires, as well as the conditions that contributed to the death and injury of people.
Table 2.
Situation with fires in the Russian Federation in 2000-2002
| Index | |||
| Number of fires, thousand Including: in cities, share of the total number of fires, % in rural areas, share of the total number of fires, % | 246,0 68,0 31,6 | 246,5 67,8 32,2 | 260,8 66,8 33,2 |
| Direct material damage from fires, thousand rubles Including: in cities, the share of the total. direct mat. damage, % in rural areas share of the total. direct financial damage, % | 54,0 45,8 | 57,1 42,9 | 54,9 45,1 |
| The number of deaths in fires, pers. Including: in cities, the share of the total. the number of deaths, % in rural areas share of the total number of deaths, % | 57,6 42,3 | 56,7 43,3 | 56,7 43,3 |
| Number of people injured in fires, people Including: in cities, the share of the total. the number of injured, % in rural areas share of the total. injured, % | 71,1 28,6 | 69,9 30,1 | 69,4 30,6 |
Table 3
Relative indicators of the situation with fires in the Russian Federation for 2000-2002
| Index | |||
| Number of fires per 1 million population, units in the cities in the countryside | 1685,6 1574,5 1973,2 | 1674,3 1578,1 2023,9 | 1781,5 1656,8 2230,3 |
| Direct material damage from 1 fire, rub. (actual prices) in cities in rural areas | 7505,0 5946,4 10869,4 | 10637,1 8953,3 14180,7 | 13291,7 10929,8 18034,5 |
| The number of people killed in fires per 1 million population, pers. in the cities in the countryside | 111,7 88,1 175,0 | 124,4 98,2 202,1 | 136,5 107,9 222,5 |
| The number of people injured in fires per 1 million people, people in the cities in the countryside | 96,2 93,7 101,9 | 96,0 93,2 108,6 | 98,9 95,6 114,1 |
| The number of people killed in fires per 1000 fires, pers. in the cities in the countryside | 66,3 55,9 88,7 | 74,3 62,2 99,8 | 76,6 65,1 99,7 |
Table 4
Distribution of the main indicators of the situation with fires in the Russian Federation in 2001-2002. for the main causes of fires.
| Causes of fires | Number of fires, units Died, man. | |
| 2001 | 2002 | |
| Set arson | ||
| Malfunction of production equipment, violation of the production process | ||
| Violation of the rules for the construction and operation of electrical equipment | ||
| Violation of the safety rules during electric and gas welding | ||
| Explosions | ||
| Spontaneous combustion of substances and materials | ||
| Violation of the rules for the design and operation of furnaces | ||
| Violation of the rules for the design and operation of heat generating installations | ||
| Violation of the rules for the operation of household gas appliances | ||
| Careless handling of fire | ||
| including prank kids with fire | ||
| lightning bolts | ||
| Unspecified causes | ||
| Other reasons | ||
| Violation of the rules for the device and operation of vehicles |
Table 5
Distribution of the main indicators of the situation with fires in the Russian Federation for 2001-2002 by types of fire objects where children and teenagers live.
| Fire objects | Number of fires, units - % of total fires Died, man. - % of the total number of deaths | |||||
| Buildings of educational institutions | 0,5 0,2 | 0,5 0,1 | ||||
| Buildings of children's institutions | 0,2 0 | 0,3 0 | ||||
| Buildings of cultural and entertainment institutions | 0,3 0 | 0,3 0,1 | ||||
| Residential buildings | 72,8 89,6 | 72,8 90,3 | ||||
| including residential buildings | 42,6 76,3 | 41,2 76,6 | ||||
| Vehicles | 6,9 1,4 | 7,4 1,1 |
Table 6
Distribution of the main indicators of the situation with fires in accordance with the age of their perpetrators in 2002
Table 7
The main indicators of the situation with fires in the Russian Federation that have arisen due to the pranks of children with fire in 2002
Table 8
The main indicators of the situation with fires in the Russian Federation for 2002, which occurred in the residential sector in buildings of various heights.
Table 9
Distribution of the number of people killed in fires by main the reasons for their death in 2000 - 2002
| Cause of death | The number of deaths, pers. / share of the total number of deaths in fires, % | |||||
| The action of combustion products | 77,71 | 78,03 | ||||
| High temperature effect | 13,87 | 13,64 | ||||
| lack of oxygen | 3,53 | 3,12 | ||||
| Collapse of structural elements, fragments in the explosion | 0,21 | 0,15 | ||||
| Exacerbation of diseases | 1,08 | 0,80 | ||||
| Manifestation of hidden diseases | 0,14 | 0,12 | ||||
| Mental factors | 0,08 | 0,08 | ||||
| Falling from height | 0,26 | 0,30 | ||||
| Electric shock | 0,16 | 0,09 | ||||
| Other reasons | 2,72 | 3,37 |
Table 10
Conditions that contributed to the death and injury of people during fires in the Russian Federation (2001 - 2002)
| Conditions that contributed to the death and injury of people | The number of deaths, pers. / number of injured people | |||||
| The state of alcoholic intoxication | 4604 | 4691 | ||||
| Leaving young children unattended | 545 | 470 | ||||
| Illness, old age, disability | 981 | 1043 | ||||
| sleep state | 1327 | 1259 | ||||
| Intensive spread of fire, high temperature on escape routes | 2599 | 2497 | ||||
| Panic, wrong actions of victims and service personnel | 1493 | 1470 | ||||
| Non-compliance of evacuation routes with fire safety requirements | 31 | 14 | ||||
| Mistakes by the fire brigade | 9 | 1 | ||||
| Structural collapse | 75 | 53 | ||||
| Other | 2751 | 2880 | ||||
| Falling from height | 149 | 135 | ||||
| Electric shock | 47 | 38 | ||||
| Criminal attacks | - | - |
Experts say
5.1. Inspector of the State Fire Supervision
Fire safety at school
What are the main issues that schoolchildren should deal with under the guidance of teachers in order to prevent a fire in the school? These questions are very varied.
Cleanliness is the key to safety
It is necessary to ensure that various combustible wastes (garbage, old desks, tables, chairs, dry leaves, etc.) do not accumulate on the school grounds. In the event of a fire, this combustible debris can help spread the fire to school buildings.
Sometimes, after cleaning the area adjacent to the school from fallen dry leaves, they are raked into heaps and burned. This is very dangerous: smoldering leaves can be carried by the wind onto the roof of a building or into a dormer window, which can lead to a fire.
It is equally important to monitor the condition of roads, driveways and entrances to school buildings, to ensure that they are not cluttered up, and in winter they are regularly cleared of snow drifts and ice. This is done to ensure that fire trucks always have the opportunity to freely enter the school grounds.
Modern fire trucks deliver the supply of water, which in most cases is enough to successfully fight a fire in the initial stage. If the fire has taken on a large size, firefighters use local water sources: reservoirs, ponds, reservoirs, fire water supply with a network of fire hydrants. All these water sources must be properly maintained.
What should be done? It is necessary to ensure that the covers of the manholes where underground fire hydrants are located are not covered with earth and debris, and that there is a fire safety sign indicating the location of the hydrant on the wall of the nearest building. This is done so that firefighters can quickly find him. During snow drifts, care should be taken to clean the mentioned hydrant covers from snow and ice.
Evacuation plan
Each school develops and hangs out in a conspicuous place an evacuation plan for people. For what purpose is it being developed?
If there is a fire in the school, first of all, it is necessary to evacuate all schoolchildren very quickly and in an organized manner. The slightest confusion, panic can lead to irreparable consequences.
The evacuation plan reflects the issues of quick notification of all teachers and students about a fire, the exit of schoolchildren from rooms that are on fire or threatened by fire and smoke, and indicates the emergency and main exits through which they must evacuate. The evacuation plan consists of two parts - graphic and text. The graphic part shows the layout of the floors of the building. Plans can be simplified by depicting structures in one line, excluding small rooms that are not related to the stay of people. But all emergency exits or routes must be shown. The name of the premises is indicated directly on the floor plans, or all premises are numbered and the explication of the premises is attached. Escape exits and stairs are numbered. This allows you to save and simplify the explanatory note to the evacuation plan. The doors on the evacuation plan are shown open. If, during operation, individual exits are closed, the doorway is depicted as closed on the evacuation plan and the location of the keys is marked with the inscription "Box with the key to the outer door."
Arrows are drawn on the plan indicating the routes of movement of people, based on the shortest exit time and greater reliability of evacuation routes.
Escape routes are divided into main ones, which are indicated by solid green lines with arrows, and reserve ones, which are indicated by dotted lines with arrows.
Practice shows that during a fire it is not always possible to bring people out through the stairs. Often people are saved by going to the roof and other air zones. If there are such zones, then the exits to them, as backup, are shown on the evacuation plan.
In addition to traffic routes, they indicate the location of manual fire detectors, fire extinguishers, fire hydrants, telephones and other equipment.
The graphic part of the evacuation plan in a frame under glass is hung in a conspicuous place, usually at the entrance to the floor. The text part of the evacuation plan is approved by the head of the facility and is a table containing a list of actions in case of fire, the order and sequence of actions, positions and names of the performers. The actions to be taken must be carefully considered and specified.
The first action is to call the fire brigade. In order for the call to be clear, the text of the call is given. The second action is an evacuation announcement. The announcement must be made in a calm but commanding and imposing tone. This can happen through a public address system, with a pre-prepared text being broadcast throughout the building.
When evacuating children in children's institutions, teachers and educators are required to:
prepare children for evacuation: stop classes, games, eating; children need to be dressed quickly;
announce the order, direction of movement and place of gathering;
· in accordance with the evacuation plan: open the doors in the direction of travel; take the children out; close the door after the children are taken out in order to reduce the rate of fire spread through the building;
Collect all children in the place provided for by the evacuation plan;
provide, if necessary, first aid;
Check the presence of children according to the list and report the results to the director or commander of the arrived fire department, the head of the fire extinguishing.
Before the arrival of firefighters, high school students can be involved in assisting teachers in organizing the evacuation of children: help them dress, take the children to a warm room; call an ambulance to provide medical assistance to the injured; carry out separate tasks for extinguishing a fire.
Each school building must have at least two emergency exits. If one of them is cut off by fire, the second is used to save people and property.
Doors on escape routes should open freely and in the direction of exit from the building. Locks on the doors of emergency exits should provide people inside the building with the ability to freely open them from the inside without a key.
It is allowed, in agreement with the State Fire Service of the Ministry of Emergency Situations of Russia, to close emergency evacuation exits to the internal mechanical lock. In this case, on each floor of the building, a responsible duty officer from among the service personnel is appointed, who always has a set of keys for all locks on the doors of emergency exits. Another set of keys must be kept at the building attendant's office. Each key on both sets must have an indication of belonging to the corresponding lock.
Search
Subscription
