Effect of noise on the human body. Why do we want silence? The negative impact of noise

Man has always lived in a world of sounds and noise. Sound is called such mechanical vibrations of the external environment, which are perceived by the human hearing aid (from 16 to 20,000 vibrations per second). Vibrations of a higher frequency are called ultrasound, a lower frequency - infrasound. Noise - loud sounds that have merged into a discordant sound.

For all living organisms, including humans, sound is one of the environmental influences. In nature, loud sounds are rare, the noise is relatively weak and short. The combination of sound stimuli gives animals and humans time to assess their nature and form a response. Sounds and noises of high power affect the hearing aid, nerve centers, can cause pain and shock. This is how noise pollution works.

Noise pollution of the environment- this is the sound scourge of our time, apparently the most intolerable of all types of environmental pollution. Along with the problems of air, soil and water pollution, mankind is faced with the problem of noise control. Such concepts as “acoustic ecology”, “noise pollution of the environment”, etc. have appeared and are becoming widespread. All this is due to the fact that the harmful effects of noise on the human body, on the human body, on the animal and plant world are undeniably established by science. Man and nature are increasingly suffering from its harmful effects.

According to I. I. Dedyu (1990), noise pollution is a form of physical pollution, which manifests itself in an increase in the noise level in excess of natural noise and causes anxiety in the short term, and damage to the organs that perceive it or the death of organisms in the long term.

The normal noise of the human environment varies between 35-60 dB. But more and more decibels are added to this background, as a result of which the noise level often exceeds 100 dB.

A decibel (dB) is a logarithmic unit of noise that expresses the degree of sound pressure. 1dB is the lowest level of noise that a person can barely pick up. Nature has never been silent, it is not silent, but silent. Sound is one of its most ancient manifestations, as ancient as the Earth itself. Sounds have always been and even monstrous strength and power. But still, the sounds of rustling leaves, the murmur of a stream, bird voices, a light splash of water and the sound of the surf, which are always pleasant to man, prevailed in the natural environment. They calm him, relieve stress. Man created, and more and more new sounds appeared.

After the invention of the wheel, he, according to the just remark of the famous English acoustician R. Tylor, without realizing it, sowed the first link in the modern noise problem. With the birth of the wheel, it began to tire and annoy a person more and more often. The natural sounds of the voices of Nature have become more and more rare, they disappear completely or are drowned out by industrial transport and other noises.
Aircraft and noise

All planes make noise, and jets make more noise than most. As a result, noise levels, especially around airports, are constantly on the rise as more jet aircraft enter the airlines and their power increases. At the same time, public discontent is growing, so that aircraft designers have to work hard on how to make jets less noisy. The roar of a jet engine is caused mainly by the rapid mixing of the exhaust gases with the outside air. Its volume directly depends on the speed of collision of gases with air. It is greatest when the engines are brought to full power before the aircraft takes off.

One way to reduce noise levels is to use turbofan engines, in which most of the intake air bypasses the combustion chamber, resulting in a reduced exhaust gas emission rate. Turbofan engines are now used in most modern passenger airliners.

Typically, the noise level of jet engines is measured in decibels (dB) of the actual perceived noise, which takes into account, in addition to the volume of the sound, also its height and duration.

Inside the ear

When a jet plane flies over you, it spreads sound waves around it in the form of fluctuations in the level of air pressure. These waves create vibrations in your eardrum, which transmits them through three small bones—the hammer, anvil, and stirrup—to your air-filled middle ear.

From there, the vibrations enter the fluid-filled inner ear, passing through the semicircular canals, which are in charge of your balance, and the cochlea. The auditory nerve responds to fluctuations in the fluid in the cochlea by converting them into encoded impulses. The impulses go to the brain, where they are decoded, and as a result, we hear a sound.

Impact of noise on organisms

Researchers have found that noise can destroy plant cells. For example, experiments have shown that plants that are bombarded with sounds dry out and die. The cause of death is excessive release of moisture through the leaves: when the noise level exceeds a certain limit, the flowers literally come out with tears. If you put a carnation next to a radio that is playing at full volume, the flower will wither. Trees in the city die much earlier than in the natural environment. The bee loses the ability to navigate and stops working with the noise of a jet plane.

A specific example of the impact of noise on living organisms can be considered the following event two years ago. Thousands of unhatched chicks died on the Ptichya spit near the Bystry branch (Danube delta) as a result of dredging operations carried out by the German company Mobius by order of the Ministry of Transport of Ukraine. The noise from the working equipment was carried for 5-7 km, having a negative impact on the adjacent territories of the Danube Biosphere Reserve. Representatives of the Danube Biosphere Reserve and 3 other organizations were forced to state with pain the death of the entire colony of the variegated tern and common tern, which were located on the Ptichya Spit.

From the Survey Report of the Ptichya Spit dated July 16, 2004: “As a result of the actual survey of the Ptichya Spit (near the Bystroe branch) at the location of large colonies of the variegated (950 nests and 430 nests - according to the results of the survey on June 28, 2004) and the common tern (120 nests - according to the same records) on an area of ​​approximately 120x130 meters and an area of ​​approximately 30x20 meters, the remains of many hundreds of eggs of these species were found. The nature of their damage clearly indicates that the chicks did not hatch from them. The estimated start of hatching of the chicks of this colony was expected from 20 July. The most likely reason for the disappearance of the colony (not even adult birds are present in its place) is an excessive disturbance factor caused by nearby dredging equipment, as well as the boats serving it.”

After that, the representative of the Ministry of Foreign Affairs of Ukraine has the audacity to declare that "The construction of the Danube-Black Sea canal does not violate the ecological balance of the Danube Delta." This was stated by the Minister of Foreign Affairs of Ukraine, Konstantin Gryshchenko, in response to calls from EU representatives and a number of international environmental organizations to stop the construction of the canal until an environmental review is carried out (according to the newspaper "Voice of Ukraine").

Using this position of the Government of Ukraine, "Ministry of Transport", "Delta-Lotsman" and "Mobius" companies are not going to make any efforts to minimize the damage from the construction of the canal.

On the contrary, on July 17, a representative of "Delta - Lotsman" announced the imminent start of the demolition of trees and the berth of the reserve in the area of ​​​​the cordon Bystroe - that is, in the territory that is not deprived of the status of a reserve.

Thus, while the President of Ukraine speaks without a shadow of embarrassment in negotiations with the European Union about the harmlessness of the canal for the unique nature of the Danube Delta, the Ministry of Transport, Mobius and Delta-Lotsman are doing everything to protect there was nothing in the Ukrainian part of the delta.

To date, about 8,000 letters from all over the world have come to various authorities in defense of the Danube Reserve.

The impact of noise on humans

Prolonged noise adversely affects the organ of hearing, reducing the sensitivity to sound. It leads to a breakdown in the activity of the heart, liver, to exhaustion and overstrain of nerve cells. Weakened cells of the nervous system cannot clearly coordinate the work of various body systems. This results in disruption of their activities.

As already mentioned, the noise level is measured in units expressing the degree of sound pressure - decibels. This pressure is not perceived indefinitely. The noise level of 20-30 decibels (dB) is practically harmless to humans, this is a natural background noise. As for loud sounds, here the permissible limit is approximately 80 decibels, and then at a noise level of 60-90 dB, unpleasant sensations arise. A sound of 120-130 decibels already causes pain in a person, and 150 becomes unbearable for him and leads to irreversible hearing loss. Not without reason in the Middle Ages there was an execution "under the bell". The hum of the bell ringing tormented and slowly killed the convict. A sound of 180dB causes metal fatigue, and a sound of 190dB pulls rivets out of structures. The level of industrial noise is also very high. In many jobs and noisy industries, it reaches 90-110 decibels or more. Not much quieter in our house, where more and more new sources of noise appear - the so-called household appliances. It is also known that tree crowns absorb sounds by 10-20 dB.

For a long time, the effect of noise on the human body was not specially studied, although already in ancient times they knew about its dangers and, for example, in ancient cities, rules were introduced to limit noise. Currently, scientists in many countries of the world are conducting various studies to determine the impact of noise on human health. Their studies have shown that noise causes significant harm to human health.

In the UK, for example, one in four men and one in three women suffer from neurosis due to high noise levels. Austrian scientists have found that noise reduces the life of city dwellers by 8-12 years. The threat and harm of noise will become more clear if we consider that in large cities it increases by about 1 dB annually. Leading American noise expert Dr. Knudsen stated that "noise is as slow a killer as it can be."

But even absolute silence frightens and depresses him. So, employees of one design bureau, which had excellent sound insulation, already a week later began to complain about the impossibility of working in conditions of oppressive silence. They were nervous, lost their working capacity. Conversely, scientists have found that sounds of a certain intensity stimulate the process of thinking, especially the process of counting.

Each person perceives noise differently. Much depends on age, temperament, state of health, environmental conditions. Some people lose their hearing even after brief exposure to noise of comparatively reduced intensity. Constant exposure to loud noise can not only adversely affect hearing, but also cause other harmful effects - ringing in the ears, dizziness, headache, increased fatigue. Very noisy modern music also dulls the hearing, causes nervous diseases. Interestingly, the American otolaryngologist S. Rosen found that in an African tribe in Sudan, not exposed to civilized noise, the hearing acuity of sixteen-year-old representatives is on average the same as that of thirty-year-old people living in noisy New York. In 20% of young men and women who often listen to fashionable modern pop music, hearing turned out to be dulled in the same way as in 85-year-olds.

Noise has an accumulative effect, i.e., acoustic irritation, accumulating in the body, increasingly depresses the nervous system. Therefore, before hearing loss from exposure to noise, a functional disorder of the central nervous system occurs. Noise has a particularly harmful effect on the neuropsychic activity of the body. The process of neuropsychiatric diseases is higher among persons working in noisy conditions than among persons working in normal sound conditions. Noises cause functional disorders of the cardiovascular system. The well-known therapist academician A. Myasnikov pointed out that noise can be a source of hypertension.

Noise has a harmful effect on the visual and vestibular analyzers, reduces reflex activity, which often causes accidents and injuries. The higher the intensity of the noise, the worse we see and react to what is happening. This list can be continued. But it must be emphasized that noise is insidious, its harmful effect on the body is completely invisible, imperceptible and has an accumulative character, moreover, the human body is practically not protected against noise. In harsh light, we close our eyes, the instinct of self-preservation saves us from burns, forcing us to withdraw our hand from hot, etc., and a person does not have a defensive reaction from exposure to noise. Therefore, there is an underestimation of the fight against noise.
Studies have shown that inaudible sounds can also have a harmful effect on human health. So, infrasounds have a special effect on the mental sphere of a person: all types of intellectual activity are affected, mood worsens, sometimes there is a feeling of confusion, anxiety, fright, fear, and at high intensity - a feeling of weakness, as after a strong nervous shock. Even weak sounds - infrasounds can have a significant impact on a person, especially if they are of a long-term nature. According to scientists, it is precisely by infrasounds, inaudibly penetrating through the thickest walls, that many nervous diseases of the inhabitants of large cities are caused. Ultrasounds, which occupy a prominent place in the range of industrial noise, are also dangerous. The mechanisms of their action on living organisms are extremely diverse. The cells of the nervous system are especially susceptible to their negative effects. Noise is insidious, its harmful effect on the body is invisibly, imperceptibly. Violations in the human body against noise is practically defenseless. Currently, doctors are talking about noise disease, which develops as a result of exposure to noise with a primary lesion of hearing and the nervous system.

Thus, noise must be dealt with, and not tried to get used to. Acoustic ecology is devoted to the fight against noise, the purpose and meaning of which is the desire to establish such an acoustic environment that would correspond or be in tune with the voices of nature, because the noise of technology is unnatural to all living things that have evolved on the planet. It should be remembered that the fight against noise was carried out in antiquity. For example, 2.5 thousand years ago in the famous ancient Greek colony, the city of Sybaris, there were rules protecting the sleep and peace of citizens: loud noises were prohibited at night, and artisans of such noisy professions as blacksmiths and tinsmiths were expelled from the city.

The fight against noise pollution

In 1959 The International Noise Abatement Organization was founded.

Noise control is a complex, complex problem that requires a lot of effort and money. Silence costs money and a lot of it. Noise sources are very diverse and there is no single way, method of dealing with them. Nevertheless, acoustic science can offer effective means of dealing with noise. Common ways to combat noise are reduced by the legislative, construction and planning, organizational, technical and technological, design and preventive world. Preference should be given to measures at the design stage rather than when the noise is already being produced.

Sanitary norms and rules establish:

maximum permissible noise levels at workplaces in the premises and on the territory of production enterprises that create noise, and at the border of their territory;
the main measures to reduce noise levels and prevent human exposure to noise.

Appropriate standards are in place and created. Failure to comply with them is punishable by law. And although at present it is not always possible to achieve effective results in the fight against noise, steps are still being taken in this direction. Special noise-absorbing suspended ceilings are installed, assembled from perforated plates, silencers on pneumatic devices and fixtures.

Musicologists offered their own means of noise mitigation: skillfully and correctly selected music began to influence the efficiency of work. An active fight against traffic noise began. Unfortunately, there is no ban on transport sound signals in cities.

Noise maps are created. They give a detailed description of the noise situation in the city. Undoubtedly, it is possible to develop optimal measures to ensure proper noise protection of the environment. The noise map according to V. Chudnov (1980) is a kind of plan for attacking noise. There are many ways to combat traffic noise: the construction of tunnel interchanges, underpasses, highways in tunnels, on overpasses and excavations. It is also possible to reduce the noise of an internal combustion engine. Jointless rails are laid on the railway - a velvet track. Actual construction of screening structures, planting forest belts. Noise standards should be reviewed every 2-3 years in the direction of their tightening. Great hopes for solving this problem are placed on electric vehicles.

Noise scale

Noise exposure level - Characteristic noise producers - Noise intensity, dB:

• hearing threshold- Complete silence - 0
• Permissible level- Noise of normal breathing - 10
• Home comfort - 20
• Sound volume norm- clock sound - 30
• The rustle of leaves in a light breeze - 33
• Volume norm during the day - 40
• Quiet whisper at a distance of 1-2 meters - 47
• Quiet street - 50
• Washing machine operation - 60
• Street noise - 70
• Ordinary speech or noise in a store with many customers - 73
• The buzz of voices in a crowded restaurant - 78
• Vacuum cleaner, highway noise with very heavy traffic, glass noise - 80
• Danger level - sports car, the maximum sound volume in the production room is 90
• Loud player music in a large room - 95
• Motorcycle, metro train - 100
• The noise of urban traffic, the roar of a diesel truck at a distance of 8 meters - 105
• The roar of a Boeing 747 taking off directly overhead - 107
• Loud music, powerful mower - 110
• Pain threshold The sound of a running lawn mower or air compressor - 112
• The roar of a Boeing 707 landing at the airport - 118
• The roar of the Concorde taking off directly overhead, a powerful roll of thunder - 120
• Air raid siren, ultra-noise fashionable electric music - 130
• Pneumatic riveting - 140
• death level- Explosion of an atomic bomb - 200

Everyone knows that air pollution negatively affects human health. However, this factor is inferior in its harmfulness to the noise that civilization surrounds us with.

The harmful effects of noise on the human body were known back in ancient China - execution with the help of noise was considered the most cruel there.

Nowadays, noise has become our constant companion. Children are especially affected by this. It has been established that the higher the level of environmental noise, the worse it affects the mental and mental state of children, especially premature ones.

In the last century, Robert Koch wrote: "Someday humanity will be forced to fight noise as decisively as it fights cholera or plague." That time has come.

Modern medicine considers noise one of the formidable enemies of human health. If he works under conditions of noise stress, he quickly gets tired, he develops insomnia, loss of appetite. Noise can cause hypotension, which is now most commonly seen in children and adolescents. With age, such patients are threatened with hypertension. A high noise level contributes to an increase in the incidence of peptic ulcer, gastritis, and, definitely, nervous diseases.

In the future, in addition to hearing disorders, cardiovascular diseases, hypertension may occur, metabolism and thyroid activity are disturbed. Under the influence of noise, brain activity is disrupted - memory and mental performance are reduced. In severe cases, psychiatric disorders may develop.

Effect of noise level

According to the Austrian scientist Griffith, noise shortens a person's life by 8-12 years. Why? The human hearing aid perceives sound intensity in the range of 0-140 decibels (dB). Noises of low intensity have a beneficial effect on a person, especially on his psyche.

Therefore, the noise of leaves, rain, sea surf, the melody of lullabies that sound with a frequency similar to the frequency of vibrations of the eardrum, have healing properties.

The rustle of leaves is perceived by a person at a level of 5-10 dB, wind noise - 10-20, whisper - 30-40, quiet conversation - 50-60, loud conversation - 60-70, in apartments that overlook the street with heavy traffic if the windows are closed, the noise reaches 60-80 dB, and if the windows are open - 80-100 dB; jet aircraft sound - 140 dB.

Noise of 20-30 dB is practically harmless to humans, it is a natural sound field, without which life is impossible.

• 30-35 dB in the territories of reserves;
• 34-37 dB in sleeping areas (houses, hospitals, apartments);
• 56-66 dB in the premises of shops, factories and the like.

Therapists believe that noise of 60-80 dB causes disorders of the autonomic nervous system in a person, 90-110 dB - hearing loss. And the noise of 115-120 dB is the "pain threshold", when the sound as such is no longer audible, but pain in the ears is felt. At 140-145 dB, eardrums can even burst. Noise of 150 dB is simply unbearable, 180 dB is fatal to humans. According to the Institute of Hygiene and Medical Ecology of the National Academy of Medical Sciences of Ukraine, the permissible noise level for teenagers is 70 dB, for adults - 90 dB.

In children who live in urban noise, there is a lag in mental development. And frequent visits to discos by teenagers can lead to hearing loss, because there "sounds" 105-110 dB, and in the case of amplification of the speakers - up to 120 dB, which is equivalent to the roar of an electric train.

Scientists have also established a direct link between noise intoxication and heart disease.

Influence of infrasounds

The most harmful to humans are infra- and ultrasounds. The fact is that a person, unlike many animals, does not hear them, and therefore does not have the opportunity to defend himself from their harmful effects. However, it should be noted that the degree of their influence depends on the frequency and time of their action. By the way, heartbeat, fluctuations of the lungs, bowel movements, vibrations of the vocal cords are also accompanied by the generation of infrasounds, but they are unlikely to harm us.

In nature, the sources of infrasounds are microseismic vibrations of the earth's surface, volcanic eruptions, interactions of the Earth's geological platforms before the formation of faults.

In an industrial society, sources of infrasounds are automobile, aircraft and rocket engines, loudspeakers and even organ pipes.

Infrasounds are perceived by our smaller friends - dogs, reptiles, fish (even aquarium ones). Therefore, you need to carefully monitor their behavior: if they react violently, be close, the danger is nearby.

According to research by the Moscow Technical University of Communications and Informatics, infrasound with a frequency of 1.2 Hz predetermines a decrease in arterial blood pressure and weakness in a person; 2.6 Hz - allergies, dermatitis, impotence.

Especially dangerous for human health are infrasounds with a frequency of 5-10 Hz (they act resonantly on the cells of living tissue, which have a natural frequency of approximately 8 Hz).

Such infrasounds harm the internal organs of a person: at a frequency of 5 Hz, the liver is damaged, 6 Hz - motion sickness develops, 7 Hz - the heart can stop and blood vessels burst.

Infrasounds of high power affect the human psyche: there is drowsiness, a feeling of fear, and the like.

But the main consequence of the action of infrasound on living organisms is a violation of the vestibular apparatus.

Infrasounds of considerable intensity can cause not only changes in auditory sensitivity, but also painful sensations, difficulty in speech and voice modulation, impaired respiratory activity, and changes in a-rhythms of the brain.

Ultrasounds (frequency over 20,000 Hz) are also not perceived by our ear.

In the conditions of modern civilization, numerous processes of industrial production and transport are a powerful source of ultrasounds. Their propagation speed depends on the properties of the medium. It is now known that low-intensity ultrasounds have a beneficial effect on living objects, and high-intensity ultrasounds are detrimental (they destroy living cells). In particular, the mechanical factor predetermined by ultrasonic radiation leads to disruption of the functions of certain parts of the body, for example, to the blockade of small capillaries by erythrocyte clots.

Thermal effects associated with the process of absorption of ultrasonic radiation by biological tissue, as a result of which part of the energy is transferred to it. This energy is converted into heat and leads to an increase in the body temperature of living organisms.

The physicochemical influence is predetermined by the change in the permeability of biological membranes and diffusion processes. The influence of ultrasound on macromolecular compounds: vitamins, hormones, enzymes has been established. Ultrasound promotes the release of biologically active substances from the organs and tissues of the body.

However, there is no sharp boundary between the zones of action of low and high intensity ultrasounds. It all depends on the nature of the biological object and a large number of external factors.

Therefore, of all noise irritants, street noises, mostly created by vehicles, cause the greatest harm.

To limit the level of noise intrusion into our lives means to preserve our health.

Aria Gvozdikovskaya
candidate of biological sciences,
member of the International Ecological Club;

Mikhail Kurik
doctor of physical and mathematical sciences, professor,
director of the Institute of Human Ecology;

“Decades have passed for us to embrace the idea of ​​the dangers of passive smoking. But it may take decades for us to learn to recognize the harm caused by “passive” increased noise.” Bradley Vite, co-author of the study.

Scientists from New York University have been researching for 5 years how noise pollution affects the human body. And they came to the conclusion that the increased noise level is no less dangerous to health than passive smoking.

Until recently, it was believed that increased noise levels were nothing more than an inconvenience that could be endured. However, this is not the case.

The latest data obtained by experts show that regular increased noise is no less dangerous for us than cigarette smoke from passive smoking. Scientists come to the conclusion that a constant noise of more than 50 decibels increases a person's stress. It also increases general anxiety, can cause hypertension. Which leads to a significant increase in the risk of a heart attack.

The EUROBUSINESS company is an authorized installer of air conditioners in Moscow.

Noise is especially unfavorable at night, when the human body must rest. But modern life "noises" every day more and more. Landing planes are noisy, motorways are noisy, where traffic does not stop for a minute. A neighbor with a perforator behind the wall is noisy, and almost all household appliances are noisy. Including climatic. In fact, it is quite difficult to hide from the constant noise even in the countryside. What can we say about cities.

Both manufacturers of equipment and consumers do not always pay attention to the selection of solutions with optimal noise parameters. It is believed that "you can tolerate" if the ventilation unit is excessively noisy. “Just turn up your TV or turn off the unit at night,” is the advice one might hear from a salesperson, “but the ventilation performance will be very good.”

Meanwhile, studies show that excessive noise is no less harmful than lack of oxygen.

“Decades have passed for us to embrace the idea of ​​the dangers of passive smoking. But it may take decades for us to learn to recognize the harm caused by “passive” increased noise.” These are the words of Bradley White, one of the authors of the study.

What level of noise is dangerous for a person?

The natural noise level is 25-30 decibels. Such noise does not harm, moreover, it is considered comfortable for a person. In terms of volume, this is comparable to the rustle of leaves on trees - the rustle of leaves is 10-20 dB. Each person has their own individual preferences for the level of noise around.

According to sanitary standards, the noise level two meters from a residential building should not exceed 55 dB. In modern cities, these norms are constantly violated.

During a normal conversation of people, the noise level reaches 40-50 decibels, as with a kettle boiling half a meter away from you. A car passing by or a tractor working 15 meters away creates a noise of about 70 dB. According to experts, the noise level on the highway in 3-4 lanes, as well as next to it on the sidewalk, exceeds the norm by 20-25 decibels. Noise leaders are airports and railway stations. The volume of the freight train is 100 dB. The noise level in the subway can reach 110 dB. But the noisiest transport is the plane. Even a kilometer from the runway, the noise level from an airplane taking off and landing is more than 100 dB.

Constant noise attacks do not go unnoticed. According to GOSTs, constant exposure to noise of 80 dB or more is considered harmful. Production with such a noise level is considered harmful. Noise at 130 dB causes a feeling of physical pain. At 150 decibels, a person loses consciousness. Noise of 180 dB is considered deadly for a person.

Why is heat dangerous?

Death by heat: how temperature will kill people. Scientists: deaths from heat will increase fivefold by 2080.

Australian scientists have published a new study. According to him, global mortality due to extreme heat will increase five times over the next 60 years. According to their forecasts, the number of deaths due to high temperatures associated with global warming will gradually increase every year on the territory of 20 states.

By 2080, the number of victims of global warming in tropical and subtropical regions will increase by almost five times. This forecast was made by scientists at the Australian Monash University in Melbourne.

Developed a computer model

To estimate the number of deaths from the heat, scientists have developed a computer model. It covers 20 countries in the period 2031-2080. They took into account the volumes of greenhouse gases emitted into the atmosphere from the combustion of fossil fuels. And also, the population density in the regions and various strategies to mitigate the effects of heat.

According to Professor Antonio Gasparrini of the London School of Hygiene and Tropical Medicine, the reason for the study was the fact that tens of thousands of people around the world suffer from health problems caused by climate warming and abnormally high temperatures associated with this process.

Scientists also came to the conclusion that in the future, periods of abnormally hot weather will be repeated more often, and their duration will increase.

“If we fail to slow down the process of climate change, deaths from extreme heat will increase. This is especially true for countries located in the equator region,” warned the author of the study, Professor Yuming Guo.

Countries at risk

According to experts, the first negative effects of global warming will be felt by residents of tropical countries with a high population density. According to the most pessimistic scenario, in the cities of Australia - Brisbane, Sydney and Melbourne - mortality from weather events will increase by 471% compared with 1971-2010. Weather phenomena can mean not only heat and drought, but also a strong storm. And also the number of deaths from the heat will increase in India, Greece, Japan and Canada, where the situation will be exacerbated by wildfires.

For countries at risk, scientists also made a number of recommendations. For example, more and better to teach people how to give first aid. And also, to revise the urban planning policy, expanding the area of ​​green areas and providing citizens with comfortable housing. The researchers also urge the authorities to provide people with constant access to drinking water.

According to Australian experts, in order to mitigate the predicted consequences, countries should not forget about the Paris Agreement, concluded in 2015. According to him, humanity should not allow the growth of the average temperature of the planet by more than one and a half degrees. Signatory countries are committed to reducing greenhouse gas emissions by 2050. To do this, they need to reorient their economies towards green technologies.

The general aggressiveness of the population is increasing

A group of researchers from Stanford University have previously stated that global warming could lead to an increase in the number of suicides.

Comparing the rate of increase in the number of episodes with abnormally high temperatures, the scientists found a clear correlation of these rates with an increase in the number of suicides.

According to their calculations, an increase in the average monthly temperature by one degree means an increase in the number of suicides. For example, the increase for the United States was 0.7 additional percent, and for Mexico it was 2.1%.

The same calculations predict that by 2050 suicides will increase by 1.4% in the United States. And in Mexico by 2.3%. In other words, an additional 14,000 to 26,000 people will take their own lives in the US alone.

The study found that the maximum number of suicides occurs at the beginning of the summer period. At this time, the general aggressiveness of the population also increases. The authors of the work blame the side effects of thermoregulation for the increase in the number of suicides in the heat. As well as other neurological reactions in response to an increase in temperature. These processes, in turn, can affect people's mental health.

The obtained data are consistent with the results of earlier works. They show that there are more suicides in the summer than in the cold months. The Stanford Group also analyzed six million tweets made by US residents.

Scientists have established a clear link between the onset of high-temperature periods and manifestations of “depressive” tweet language. He becomes rich in words such as "lonely", "driven", "suicidal", etc.

According to experts, an increase in temperature above the norm by one degree Celsius increases the depressiveness of the American language by 0.79%.

If your workplace is noisy, you may be at risk for hearing loss. Hearing loss is one of the most common occupational diseases. How do you know if your working conditions are dangerous and when to see a doctor?

Noise norms

It is believed that sounds up to 75 dB do not affect hearing in any way, therefore, it is prescribed in sanitary standards that the noise level at work should not exceed 80 dB. And the harder the work, the lower this limit. But what do these numbers mean?

For comparison, the noise level during a conversation is 60-65 dB, on a busy street - 75-85 dB. But not only constant noise pollution is harmful to the human ear - sharp loud sounds (especially more than 140 dB) are also harmful. The same sanitary standards do not allow this figure to be higher than 125 dB.

How is noise harmful?

How can working in a factory, at an airport, near a highway, or with a lawn mower or a drill impair your hearing? The human ear is quite complex and delicate, and noise can cause three types of damage:

1. Damage hair cells. They are located in the inner ear and transmit vibrations received from the outside. Hearing loss usually occurs gradually and imperceptibly. The first symptom most often becomes immunity to high frequencies. Noise levels greater than 105 dB can lead to this if a person is exposed to it for at least 15 minutes every week. If every day for several hours the noise level reaches 80-90 dB, this is also harmful to health. In other words, both the level of noise and how long it affects a person is important.

Toxic substances to the ear, together with noise, can cause more severe damage. Therefore, you should be especially careful with some organic solvents, including toluene, styrene and carbon disulfide.

1. tinnitus(noise in the ears: ringing, buzzing, hum, whistle). This condition may pass in a few hours, but in rare cases it remains permanently. The development of tinnitus is also bad because it often interferes with sleep. There is no specific treatment for it. In some cases, tinnitus is a precursor to hearing loss.
2. tympanic membrane rupture and damage to the ossicles in the middle ear. This can be caused by a harsh, very loud sound. But most often, such exposure only affects hearing for a few hours or a couple of days.

If a pregnant woman works in conditions of noise pollution, it can also be dangerous for her and the fetus. Loud noise leads to high blood pressure and fatigue. There is also evidence that noise can impair a child's hearing, especially the perception of low frequencies.

Noise at work is also chronic stress, and it is not necessary for the sounds to be loud. Even constant conversations at the next table can regularly cause negative emotions. Perhaps this is why noise has been shown to increase the risk of heart disease.

How to protect yourself in noisy work?

Hearing loss due to regular noise exposure is irreversible. Therefore, it is very important to prevent harm to health and regularly. You can determine the noise level using a special device. There is also a less accurate, but easier way: if you cannot hear a person who is not screaming and is two meters away from you, then the noise level is threatening.

If you are affected by more than 75 dB, then you need to wear anti-noise headphones or earplugs (they remove up to 25 dB) or at least sometimes move away from the noise. Often even a 10-minute break will help recovery. However, after 2 hours at 100 dB, a 16-hour rest is needed. If a loud sound causes pain, move away from the source immediately.

When evaluating the harm to the body from noise, keep in mind that with an increase in its level by 3 dB, the safe exposure time is halved.

Sometimes employers don't want to do anything about noise pollution. In this case, you can contact the personnel department, the trade union, if any, or the labor inspectorate. The requirements of labor legislation are designed to protect human life and health. Professional examinations of people working in noisy areas should be carried out regularly. This will keep your health and hearing.

Medical examination and hearing test

If you work in a high noise environment, it makes sense to have regular check-ups with your doctor for hearing loss. Between consultations, you can evaluate your hearing yourself by downloading the app for your smartphone. Also look out for the following symptoms:

• it is difficult for you to understand what a person is saying if there is background noise (for example, in a cafe);
• it seems to you that people are muttering something, not talking;
• you have to ask people to repeat what they have said;
• you have difficulty understanding what is being said on the phone;
• you hear ringing or other noises in one or both ears.

For each of us there is natural noise level(25-30 decibels).

Such Noise does not harm, moreover, it is considered comfortable for a person. In terms of volume, this is comparable to the rustle of leaves on trees (the rustle of leaves is 10-20 decibels)

In addition, each person has individual preferences for the level of noise around.

According to sanitary standards, the noise level two meters from a residential building should not exceed 55 decibels.

In modern cities, these norms are constantly violated.

During a normal conversation of people, the noise level reaches 40-50 decibels. A kettle boiling half a meter away from you "pulls" 40-50 decibels. A passing car generates a Noise of approximately 70 decibels. The same Noise stands 15 meters from a working tractor.

According to the estimates of the Specialists, the noise level on the highway in 3-4 lanes, as well as next to it on the sidewalk, exceeds the norm by 20-25 decibels.

Noise leaders are airports and train stations. The volume of the commodity composition is 100 decibels.

Noise level in the subway can reach 110 decibels.

But the noisiest transport is the plane. Even a kilometer from the runway, the noise level from an airplane taking off and landing is more than 100 decibels.

What level of noise is dangerous for a person?

According to GOSTs, permanent exposure to Noise at a level of 80 decibels or more is considered harmful. Production with such a noise level is considered harmful. Noise at 130 decibels causes a sensation of physical pain. At 150 decibels, a person loses consciousness. Noise of 180 decibels is considered deadly for humans.

Constant "Noise Attacks" do not go unnoticed for the Rumor.

Loud noise can cause acoustic injury.

It is acute and chronic.

Acute acoustic trauma arises from sharp Sounds of great power, for example, a train whistle, resounding dangerously close to the ear.

Its consequences are unpleasant: pain in the ear, accompanied by hemorrhage in the inner ear.

For some time, Hearing is greatly weakened and it may seem to a person that he has become deaf.

Sometimes acoustic trauma can be combined with barotrauma - from excessive pressure, the tympanic membrane ruptures and hemorrhages into the tympanic cavity. They die from this hair cells, responsible for the perception of sounds.

Chronic acoustic trauma occurs much more frequently. This is the case when the level of Noise in the premises is above the permissible, but in general it seems tolerable. With a long constant stay in such a room, Hearing becomes dull, because. the hearing organs are affected by the fatigue factor.

Chronic acoustic trauma can be even more dangerous than acute one. A lot depends on the height of the Sounds. The most harmful are sounds with a high frequency of oscillation - more than 2000 Hz. The nerve cells of the inner ear are especially sensitive to just such Sounds,

At high levels of Noise, hearing impairments appear after 1-2 years, at medium levels - after 10-12 years.

In some professions Deafness is an occupational disease. The risk group includes boiler workers, riveters, weavers, motor testers, train drivers, etc.

How to Protect Your Hearing?

In noisy factories, workers use ear plugs and headphones. This is a sanitary requirement.

This is doubly important if you have to work indoors.

Try to create a comfortable sound environment at home and at work.

Choose the optimum volume for the radio and TV.

We often turn up the volume "in reserve". This is a bad habit that should be gradually abandoned.

If you are tormented by strong noise outside the window, double-glazed windows with a PVC profile or a wooden profile can become a salvation.

Take care of your Hearing and it will stay with you for many years!