What is the effect of noise. Effect of noise on the human body. Specific and non-specific effects of noise. Impact of noise on organisms

Noise under certain conditions can have a significant impact on human health and behavior. It can cause irritation and aggression, arterial hypertension (increased blood pressure), tinnitus (tinnitus), hearing loss. Noise in the frequency range of 3000 - 5000 Hz causes the greatest irritation.

Chronic exposure to noise above 90 dB can lead to hearing loss.

With noise at a level of more than 110 dB, a person experiences sound intoxication, which, according to subjective sensations, is similar to alcohol or drugs.

At a noise level of 145 dB, a person's eardrums rupture.

Women are less resistant to loud noise than men. In addition, susceptibility to noise also depends on age, temperament, health status, environmental conditions, etc.

Discomfort is caused not only by noise pollution, but also by the complete absence of noise. Moreover, sounds of a certain strength increase efficiency and stimulate the thinking process (especially the counting process) and, conversely, in the absence of noise, a person loses working capacity and experiences stress. The most optimal for the human ear are natural noises: the rustle of leaves, the murmur of water, the singing of birds. Industrial noise of any power does not contribute to the improvement of well-being.

Scientists distinguish the following gradations of noise action: 1. Interfering action. It increases with increasing volume, but depends on individual perception and on the specific situation. Even a barely audible sound can become a hindrance, for example, the ticking of a clock, the buzzing of a fly, the dripping of water from a tap. The stronger the volume of a sudden noise interference differs from the level of the general background noise, the more unpleasant it is for the ear. Here is how the director of the Institute for Occupational Hygiene and Occupational Medicine at the Essen Clinic, Professor Werner Klosterketter, says about the impact of noise on the human body: irritation, resentment. This means that the psychological and social well-being of a person is violated. Depending on the strength of the unpleasant emotions caused by the noise, the autonomic nervous system also more or less reacts to the noise. Through habituation, the unpleasant psychological effects of noise can be reduced or completely eliminated. This fact must be taken into account when planning districts of the city. Being on the street or at the workplace, due to habit, they are ready to endure noises louder than at home, where, according to many studies, the upper limit of habituation is about 40 dB (A) during the day, in any case not more than 45 dB (A), and at night - 35 dB(A)”. 2. Activation, that is, excitation of the central and autonomic nervous system, sleep disturbance, impaired ability to relax, a marked increase in reactions associated with fear. This type of noise exposure is characterized by a slight increase in blood pressure, dilated pupils, decreased stomach motility, secretion of gastric juice and saliva, increased respiratory rate and pulse rate, increased muscle activity and skin electrical resistance, and increased release of hormones that play a role in the functioning of the autonomic nervous system. . The threshold for some of these reactions is quite high (eg skin blood flow changes from 70-75 dB(A)); in other reactions it is very low (for the electrical resistance of the skin - starting from 3-6 dB(A) above the background noise level). As far as we know, in a sleeping person the threshold of auditory perception is 10-14 dB lower than in the waking state. When resting, the nervous system is at an average level of activation. Sound stimuli can sharply raise this level, prevent the release of tension. Noise is especially disturbing during the rest period, especially during sleep. Now many people complain about sleep disturbance, and there are more and more cases of insomnia caused by noise. Noise makes it difficult and slows down falling asleep, can wake a person at night, and even if it doesn’t come to that, night noise still has a bad effect on sleep. Since there is an activating effect of noise. Non-monotonic noise with large volume jumps, for example, from airplanes, passing cars, as well as information-carrying noises (conversations, radio, TV) are especially disturbing. Sudden short-term noises, for example, slamming doors, gunshots, barking dogs, and so on, the level of which exceeds the background noise by more than 10-15 dB(A), should also be attributed to especially interfering ones. But continuous noise that does not give pauses for rest is also very unpleasant. The probability of awakening from noise depends on the phase of sleep. 3. Impact on performance. There have been many scientific studies on the effect of noise on performance. Almost all of them showed that habitual and expected noises do not worsen, and sometimes even improve their performance due to the activation reaction, but noise, especially unexpected, unusual and undesirable, can reduce the performance of tasks that require a lot of concentration. Simply put, while music at low to moderate volumes can have a positive effect on us at work, unwanted noise can reduce or impair our productivity and ability to concentrate.

4. Interference for the transmission of information and violation of the general orientation in the sound environment.Speech intelligibility, acoustic orientation in the environment and the perception of warning signals are impaired by noise the stronger, the higher its level. For example, noise interference during a conversation should be at least 10 dB(A) quieter than the speech of the interlocutors. A particular problem in industrial, residential and educational premises is communication interference with extraneous noise (industrial noise, traffic noise, etc.), which mask the sounds of speech. Thus, information-carrying noise can be combated by means of neutral noise. 5. Constant exposure to noise can cause deafness due to damage to sound-sensitive cells in the inner ear. The danger of permanent deafness occurs if a person is exposed to noise with an average level of more than 85 dB(A) for many years every day for 8 hours. This level, as a rule, is achieved only in production. It is estimated that approximately 10-15% of industrial workers are exposed to noise levels above 85 dB(A). People working in ferrous and non-ferrous metallurgy, in the textile industry and in underground construction suffer the most from noise. Noises with an intensity of over 100 dB(A) are noted here. Dangerous and construction noise produced by machines that work on construction sites, as well as trucks delivering materials. The noise of the mechanisms used here is very diverse. So a jackhammer at a distance of 7 m creates a noise of 90-100 dB (A), which is almost twice as loud as the noise of a truck. Outside the workplace, hearing damage can be caused mainly by too noisy leisure activities, shooting sports or musical hobbies. The traumatic effect of noise on the human body consists of several components. The changes that occur in the organ of hearing are associated with the damaging effect of noise on the peripheral part of the auditory analyzer - the inner ear. The primary localization of the lesion is the cells of the internal spiral groove and the organ of Corti.

Along with this, in the mechanism of the effect of noise on the organ of hearing, an overstrain of the inhibitory process plays a significant role, which, in the absence of sufficient rest, leads to the depletion of the sound-receiving apparatus and the redistribution of the cells that make up its composition.

Prolonged exposure to noise causes persistent disturbances in the circulatory system of the inner ear. This is the cause of subsequent changes in the labyrinth fluid and contributes to the development of degenerative processes in the sensitive elements of the organ of Corti.

In the pathogenesis of occupational damage to the organ of hearing, the role of the central nervous system cannot be excluded. Pathological changes that develop in the nervous apparatus of the cochlea during prolonged exposure to intense noise are largely due to overwork of the cortical auditory centers.

The auditory analyzer has extensive anatomical and physiological connections with various parts of the nervous system. An acoustic stimulus, acting through the receptor apparatus of the auditory analyzer, causes reflex shifts in the functions of its cortical section and other organs and systems of the human body.

The symptom complex that develops in the body under the influence of noise is called noise disease .

Clinical picture . Clinical manifestations of noise disease consist of specific changes in the organ of hearing and non-specific changes in the central nervous and cardiovascular systems. Occupational hearing loss is usually bilateral and proceeds according to the type of cochlear neuritis.

As a rule, persistent changes in hearing are preceded by a period of adaptation to noise. During this period, there is an unstable hearing loss that occurs immediately after the action of an acoustic stimulus and disappears after the termination of its action. Adaptation is a protective reaction of the auditory analyzer. The development of persistent hearing loss occurs gradually.

The initial stage of the disease may be preceded by a sensation of ringing or noise in the ears, dizziness, headache. The perception of spoken and whispered speech during this period is not disturbed.

A special place in the pathology of the organ of hearing is occupied by lesions caused by exposure to superintense noise and sounds. Even with a short-term effect, they can cause complete death of the spiral organ and rupture of the eardrum, accompanied by a feeling of congestion and sharp pain in the ears. The outcome of such an injury is complete hearing loss.

Nonspecific manifestations of noise disease are the results of functional disorders of the nervous and cardiovascular systems. They occur during prolonged systematic exposure to intense noise. The nature and degree of disturbances largely depend on the intensity of the noise.

Prolonged exposure to intense noise develops asthenovegetative syndrome, vegetative vascular dysfunction.

In the neurological picture, the main complaints are a headache of a dull nature, a feeling of heaviness and noise in the head, appearing at the end of a work shift or after work, dizziness when changing body position, irritability appears, working capacity, memory and attention decrease, sleep disturbance (drowsiness during the day, disturbed sleep or insomnia at night). Increased sweating is also characteristic, especially when agitated.

When examining such patients, a small tremor of the fingers of outstretched hands, a tremor of the eyelids are observed, tendon reflexes are reduced, pharyngeal, palatine and abdominal reflexes are depressed, a decrease in the excitability of the vestibular apparatus, and muscle weakness are noted. Pain sensitivity in the distal extremities is disturbed, vibration sensitivity is reduced. A number of functional and endocrine disorders are revealed, such as hyperhidrosis, persistent red dermographism, coldness of the hands and feet, depression and perversion of the oculocardial reflex, an increase or inhibition of the orthoclinostatic reflex, and an increase in the functional activity of the thyroid gland.

Changes in the cardiovascular system in the initial stages of the disease are functional. During the stay in noise conditions, instability of the pulse and blood pressure is observed. After a working day, bradycardia is noted, diastolic pressure rises, functional heart murmurs appear. Patients complain of palpitations, discomfort in the region of the heart in the form of tingling.

The electrocardiogram reveals changes that indicate extracardiac disorders: sinus bradycardia, bradyarrhythmia, a tendency to slow intraventricular or atrioventricular conduction. Sometimes there is a tendency to spasm of the capillaries of the extremities and the vessels of the fundus, as well as to an increase in peripheral resistance.

Functional shifts that occur in the circulatory system under the influence of intense noise, over time, can lead to persistent changes in vascular tone, contributing to the development of hypertension.

Diagnostics. The professional nature of the damage to the organ of hearing is established on the basis of the clinical picture of the gradual development of the disease according to the type of bilateral cochlear neuritis. The length of service in conditions of exposure to intense noise, the possibility of developing the disease due to infectious diseases (neuroinfection, influenza, meningitis), contusion or taking certain medications (such as streptomycin, quinine, etc.)

Treatment. Hearing loss syndrome is not always treatable, and full recovery of hearing cannot be expected. Perhaps only a slight improvement in hearing after the cessation of work in conditions of exposure to noise with persistent drug treatment. They use vasodilators (nicotinic acid, reserpine), drugs that improve neurotrophic regulation in the inner ear. Fortifying agents (aloe), vitamin therapy are used.

In the complex of therapeutic measures, physiotherapeutic methods are used: diathermy, paraffin, silt, mud therapy on the area of ​​the mastoid processes, ionogalvanization with potassium iodide ions, local darsonvalization, hydrochloric-coniferous and hydrogen sulfide baths.

Prevention. Measures to prevent the harmful effects of noise on the human body should primarily be aimed at reducing the noise level. This can be achieved by improving the design of machines, tools and other equipment, using sound-absorbing and sound-insulating materials. If these measures do not reduce the noise level to safe limits, it is advisable to use personal protective equipment (headphones, helmets).

Preliminary (when applying for a job) and periodic medical examinations are important. Depending on the time of exposure, noise can lead to more or less severe stress, and stress can upset a person's “internal clock”.

Diseases caused by occupational noise exposure (noise disease) Noise disease is understood as persistent, irreversible morphological changes in the organ of hearing, due to the influence of industrial noise. At acute heavy-duty noise exposure and sounds, the death of the spiral (Corti) organ, rupture of the eardrums, and bleeding from the ears are observed. At chronic exposure to occupational noise there is atrophy of the spiral organ with its replacement by fibrous connective tissue. There may be no changes in the auditory nerve. There is stiffness in the joints of the auditory ossicles.

Accident, illness, exposure to noise can seriously impair the function of the ears. A foreign body can rupture the eardrum, and a blow to the head can damage the middle or inner ear. The disease can affect the middle ear or destroy the sensitive hair cells on the basilar membrane, but worst of all, when the auditory nerve is damaged and its connections with the brain are disrupted, deafness of perception occurs.

With all types of deafness, except for the last one, medicine is able to help the victim: the damaged eardrum and auditory ossicles are replaced by transplantation or implantation of artificial plastic bones. If the hair cells in the cochlea begin to lose sensitivity, amplifying the sound entering the external auditory canal may help; but when the auditory nerve dies, the ear as a sense organ becomes completely useless.

The most common and serious cause of noise-induced hearing loss is exposure to high noise levels in workplaces, whether in the cab of a diesel truck, a foundry, or anything from a print shop to a synthetics factory. If we exclude explosions and shooting, then hearing damage from noise outside of work is an unlikely event. No matter how irritating a person is the noise of aircraft or ground transportation, it is unlikely to cause physiological hearing damage. Perhaps the exceptions are motorcycles of some brands and, as we have already said, pop music orchestras. How exactly does noise affect its victims? What noise level should be considered dangerous? Is hearing damage reversible?

Noise can affect hearing in three ways: cause instant deafness or hearing damage; with prolonged exposure - sharply reduce sensitivity to sounds of certain frequencies, and, finally, noise can reduce hearing sensitivity for a limited time - minutes, weeks, months, after which hearing is restored almost completely.

The first type of injury, acoustic trauma, is usually caused by exposure to very high intensity noise, such as an explosion. For obvious reasons, it is impossible to establish experimentally the minimum level of noise that leads to damage of this kind; but it appears that impulsive noise in excess of 150 dB causes injury instantly. In this case, the eardrum may be irreparably torn, and the auditory ossicles may be broken or displaced. However, it is possible that the snail will still survive, since damage to the ossicles can prevent the transfer of all noise energy to the perilymph.

Explosions are not the only source of impulsive noise. Hitting a steel plate with a hammer also produces a significant pulse of noise, although not as high as an explosion. Impulses of lower intensity also injure hearing, but cause damage not in the middle, but in the inner ear, as well as continuous noise, which will be discussed later. As we already know, there are two protective devices in the human ear: one of them is the ear reflex. Unfortunately, it fires within about 10ms (milliseconds), during which time the impulse noise can already cause injury. But such impulsive noise with a very short rise time is almost never found in nature, it is generated only by man.

Another powerful source of impulsive noise is the sonic boom produced by aircraft. First of all, however, it should be said that, according to the generally accepted opinion, a peak overpressure of 35,000 N/m 2 is required to rupture the eardrum, and 100,000 N/m 2 to damage the lungs. The excess pressure created by supersonic aircraft very rarely exceeds 100 N/m 2 .

However, hearing damage from impulsive noise is not the main cause for concern. Much more detrimental to hearing are long periods of continuous exposure to high-intensity noise. This type of noise acts in two ways, and the first type of impact may not cause serious harm. Thus, if a person is exposed for more than a few minutes to medium or high frequency sound with a level of about 90 dB or a little higher, he then experiences a so-called "temporary threshold shift". The normal hearing threshold is the lowest level at which a given person can still hear a sound of one frequency or another; after exposure to strong noise, this threshold increases markedly. However, this decrease in hearing will last no more than half an hour, after which the residual threshold shift will become imperceptible.

With an increase in exposure time and with an increase in the noise level, the time shift of the threshold increases and the recovery period lengthens. If, for example, a noise of 100 dB at frequencies of 1200-2400 Hz lasted 100 minutes, then the temporal threshold shift will exceed 30 dB, and it will take about 36 hours to restore normal hearing.

If exposure to high noise does not occur systematically, then the residual effect is so small that it can be neglected. However, many people around the world are constantly exposed to high levels of noise in production or other work; the effect ceases to be temporary, and over the years, hearing loss becomes severe and chronic. Usually noise victims tend to deny that they are not all right with their hearing.

Not all people react the same way to noise. The same dose of noise exposure causes hearing damage in some people, not in others, and in some this damage can be more severe than in others. Therefore, any acceptable noise limit should always be assessed in terms of the number of people (percentage) who suffer less damage after exposure to noise than some chosen limit. The limits taken from the code guarantee that in 90% of people the specified noise doses will cause a residual hearing loss of less than 20 dB after 50 years of work at the specified noise exposure dose. Lowering the limits by 5 dB will increase this figure to 93%, and lowering by 10 dB will increase this figure to 96%. Hearing loss of more than 20 dB begins to seriously interfere with a person when age-related hearing changes are added to this. Hearing loss less than 20 dB is not very significant, but 10 dB is almost imperceptible.

As a rule, a noise so loud that it is impossible to talk without turning into a scream already carries the risk of hearing damage. It can be argued that if a person who does not systematically work in a noise zone receives a temporary shift in the hearing threshold after being in it, then the noise level in the zone is likely to exceed 90 dBA. In general, regardless of the duration of exposure, leaving the ears unprotected at a noise level of 120 dB is unreasonable, and at a level reaching 135 dB it is dangerous. Even with ear protectors, the absolute noise limit is 150 dBA, and since many types of protectors only reduce levels by 20 dBA or less, wearing them does not eliminate the risk of hearing damage if you are in a noisy area all day.

Occupational noise-induced hearing loss, in other words, occupational hearing loss, is perhaps the most serious exposure to noise, but it is not the only one. Noise has many other harmful effects on a person: certain types of noise and vibration cause diseases; noise can seriously disrupt communication, it often leads to accidents; with a constant irritating effect, noise can cause mental disorders; noise interferes with sleep and interrupts sleep, and the results of this can be quite serious. In short, noise worsens the human condition.

Not all the harmful effects of noise and its accomplice - vibrations have been fully disclosed yet. People who work with vibrating hand tools are known to suffer from diseases known as "white fingers", "dead hand", "Raynaud's phenomenon". The symptoms are pain, numbness, and cyanosis of the fingers, as from exposure to cold. Very often there is damage to the joints and bones of the hands, and the joints swell and lose mobility. It is possible that damage to bones and joints occurs as a result of repeated sharp blows to which the hands are exposed when working with impact mechanisms, and other symptoms are caused by high-frequency vibrations.

Other harmful effects of noise and vibration on the body are not currently considered serious, with the exception of exposure to sounds of very high or very low frequencies, as well as very high intensity. Noise of very high intensity can cause resonance in the semicircular canals, the organs of balance in the inner ear, leading to dizziness and nausea. Ultrasonic noise with a frequency above the limit of hearing can also cause nausea, and infrasound and very low-frequency audible noise excite resonances in the internal organs, including the heart and lungs. Acoustic excitation with a certain frequency and a sufficiently large amplitude can stop the pulsation of the heart. Strong low-frequency noise makes it difficult to breathe.

The psychological and other non-pathological effects of noise exposure are also important, but they are not always measurable. How to measure the degree of irritation experienced by a person? How much harm does a bad mood do? Annoyed people sometimes become unnaturally quick-tempered or make completely wrong decisions, which can sometimes lead to disastrous consequences. Noise victims may develop depression or psychosomatic susceptibility; families are destroyed, accidents occur, relations at work are complicated.

Noise causes both normal fatigue and an inability to concentrate, also leading to reduced productivity and accidents. It is not easy to measure the dependence of labor productivity on noise: as soon as we select a group of subjects and begin to experiment, changing the surrounding conditions, whether it be acoustics, lighting or heating, the productivity of the subjects immediately increases simply because they feel that they are taking care of their health and trying to help them in some way. However, few will dare to deny that people who work in conditions of strong noise are more likely to make mistakes and, consequently, their work is less productive and efficient. It has also been found that when the noise level decreases, the number of absenteeism decreases.

Sleep disturbance is probably the most serious damage that noise brings to a person, excluding, of course, hearing damage. To perform effectively, mentally and physically, almost everyone needs adequate sleep. It should be remembered that when a person sleeps, his senses, including the ears, remain "on". If during sleep we do not hear low-level sounds, this does not mean at all that our ears do not pick them up, but that the brain simply reacts differently to auditory stimuli. As you know, even under anesthesia, nerve impulses continue to be transmitted to the higher centers of the brain. Low-level noise may not have a visible effect on sleep, but the fact that noise is perceived is revealed by careful analysis of the electroencephalogram (EEG). During deep sleep, a click of 50-60 dBA causes an easily identifiable cortical response. Noises of higher levels cause very pronounced changes in the EEG.

The easiest way to consider that the effect of noise on sleep is that a person wakes up under the influence of noise. Of course, this is a very important point, but many underestimate the importance of a forced shift in the depth of sleep that does not yet lead to awakening. As experiments show, if a sleeping person, who has barely reached the stage of the deepest sleep, is influenced in such a way that, without waking up, he is transferred to a stage of less deep sleep, the result is the same as with full awakening.

Sudden awakening from deep sleep may be accompanied by palpitations. If a person is awakened every time he reaches the stage of dreaming (easily identified by rapid eye movements), and thus deprived of dreams, he develops symptoms that eventually lead to hallucinations and disorientation.

Noise causes both shifts in the depth of sleep and full awakening. It is well known that people over the age of 60 are more easily awakened or put into a state of less deep sleep than children or middle-aged people. Differences in reaction are sharply expressed; It has been established that noise, which wakes up only 5% of children aged 7-8, causes a complete awakening of 70% of people aged 69-72 years. An older person who is awakened has a harder time falling asleep again than a child or a middle-aged person. It has also been proven that women wake up more easily from noise than men.

If we compare the changes in sleep caused by noise with the normal sleep process, it is easy to understand how significant the role of ambient noise is. It is known that for the sleeper the most beneficial stage of deep sleep, and in order to reach it, it takes an adult about an hour, and it is obvious that a few short-term noise stimuli during the night are enough to cause a serious disturbance of full sleep. Of the same importance is the stage of dreams, frequent awakenings during which can greatly affect the quality of sleep.

A secondary manifestation of the effect of ambient noise on sleep was also studied, namely, the lengthening of the period necessary for the onset of the stage of deep sleep. Within certain limits, the brain is able to compensate for disturbances in the quality of sleep in noisy conditions and to compensate for the lack of deep sleep at the beginning of the night by increasing the duration of the deep sleep stage and its greater stability in the later hours (reverse normal order).

In terms of acceptable nighttime noise limits, it should be noted that noise at a constant level has less effect on sleep than noise with fluctuating levels or intermittent noise. So it's more important to try to prevent a few short "bursts" of noise than to try to reduce the overall noise level. Here, as in other situations, the presence of a suitable background can be of great help in cases where high-level intermittent noise cannot be avoided. In the tropics, where noisy air-conditioning devices built into windows are very common, it is certainly much easier for a person to sleep if such a device is not controlled by a thermostat, but operates continuously.

With a background noise of 35 dBA, individual noise peaks with a level of 45-50 dBA, although they seem too high, are practically quite acceptable for 80% of sleeping people; as the number of noise maxima increases, this limit should be lowered.

Finally, noise creates another problem - communication disruption. In many everyday situations it is very important that one person can quickly and accurately convey information to another. Communication disruption can lead, firstly, to a decrease in labor efficiency and, secondly, to much more serious and even fatal consequences. Often, accidents can be prevented by shouting: “Look out!”. Obviously, if the ambient noise prevents such warnings from being heard, people will die from causes that could have been prevented.

1 According to researchers, "noise pollution", which is now characteristic of large cities, reduces the life expectancy of their inhabitants by 10-12 years. The negative impact on a person from the noise of a metropolis is 36% more significant than from tobacco smoking, which shortens a person's life by an average of 6-8 years.

Noise - random fluctuations of various physical nature, characterized by the complexity of the temporal and spectral structure. From a physiological point of view, noise can be called any unwanted sound (simple or complex) that interferes with the perception of useful sounds (human speech, signals, etc.) that break the silence and have a harmful effect on a person.

The human body reacts differently to different levels of noise. Level Noises 70-90 dB with prolonged exposure lead to a disease of the nervous system, and more 100 dB- to hearing loss, up to deafness.

Noise creates a significant load on the human nervous system, exerting a psychological impact on it. Noise can increase blood levels of stress hormones such as cortisol, adrenaline and norepinephrine - even during sleep. The longer these hormones are present in the circulatory system, the more likely they are to lead to life-threatening physiological problems.

According to World Health Organization (WHO) guidelines, cardiovascular disease can occur if a person is constantly exposed to loud noise at night. 50 dB or higher - such noise is emitted by a street with light traffic. In order to earn insomnia, enough noise in 42 dB; just to get irritable - 35 dB(whisper sound). According to the WHO, thousands of people in the UK and around the world die prematurely from heart problems caused by long-term exposure to elevated noise levels.

Under the influence of noise 85 - 90 dB reduced hearing sensitivity at high frequencies. For a long time, a person complains of malaise. Symptoms - headache, dizziness, nausea, excessive irritability. All this is the result of working in noisy conditions. Under the influence of strong noise, especially high-frequency noise, irreversible changes occur in the hearing organ. At high noise levels, hearing sensitivity drops after 1-2 years, at medium noise levels it is detected much later, after 5-10 years, that is, hearing loss occurs slowly, the disease develops gradually. Therefore, it is especially important to take appropriate noise protection measures in advance. Nowadays, almost everyone exposed to noise at work is at risk of becoming deaf.

It is too noisy in Irkutsk - more than 1/3 of the city's population lives in the zone of acoustic discomfort today. The urban noise of Irkutsk is determined mainly by traffic noise. The calculations of the level of transport noise in the city territory, carried out by ISMU, made it possible to identify vulnerable residential areas near the highway, where the noise level exceeds the permissible by 6.5 dBA, and the noise in residential buildings - by 4-13 dBA. The population living in the main areas, notes the deterioration of health, headaches, sleep disturbance, the functions of the cardiovascular system and the gastrointestinal tract.

An effective way to solve the problem of noise is to reduce its level at the source itself by changing the technology and design of machines. Measures of this type include the replacement of noisy processes with silent ones, shock processes with non-impact ones, for example, the replacement of riveting with soldering, forging and stamping with pressure treatment; replacement of metal in some parts with non-sound materials, the use of vibration isolation, silencers, damping, soundproof casings, etc.

Noise protection includes the following activities.

1)Sound absorption. Sound absorption is the process of transferring part of the energy of a sound wave into the thermal energy of the medium in which the sound propagates. For sound absorption, porous (pores must be open from the side of sound incidence and interconnected) and loose fibrous materials (felt, mineral wool, cork, etc.) are used.

Sound-absorbing materials or structures made of them are fixed on the enclosing structures of the room without an air gap or at some distance from them.

2) Soundproofing. Soundproofing refers to the process of reducing the level of noise penetrating through the fence into the room.

The main parameter for assessing the sound insulation of any structure is the Rw index. It shows how many decibels the noise level is reduced when using a soundproof structure. To achieve a noise level comfortable for a person (no more than 30 dB), interior partitions must have an Rw index of at least 50 dB.

Bibliographic link

Shishelova T.I., Malygina Yu.S., Nguyen Xuan Dat INFLUENCE OF NOISE ON THE HUMAN BODY // Successes of modern natural science. - 2009. - No. 8. - P. 14-15;
URL: http://natural-sciences.ru/ru/article/view?id=14048 (date of access: 03/02/2020). We bring to your attention the journals published by the publishing house "Academy of Natural History"

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"It gets on my nerves!"- Your first reaction to the roar of a siren or a strong roar.

According to scientists, frequencies outside the gamut of sounds of the human voice often have detrimental effects on our nervous system.

We are talking about the number of acoustic vibrations per second (Hz) when their frequency is either too weak (very low sounds) or too high.

The fight against noise has been going on for a very long time. As early as three thousand years BC, in the state of the Sumerians, gunsmiths were not allowed to keep workshops in the city center. The ancient Greeks and Romans put straw under their chariots to muffle the rumble of the wheels. Then there was a ban on rooster singing before dawn. A rooster that crowed before the appointed time was immediately sent to the spit. In England, which retains its laws adopted several hundred years ago, one of them has not yet been repealed, which prohibits hitting wives between 10 pm and 5 am. In parallel with new inventions that make life easier for people, they also invented ways to reduce their noise effect. Silent trams appeared, soundproof walls and windows, almost silent refrigerators, passengers of an airliner do not hear the roar of its engines.

Noise not only causes hearing impairment, but also negatively affects the psyche. At first, there is some kind of dullness from the noise, and then the opposite effect begins: the excitation of the body, as from strong coffee. This is followed by aggressiveness, irritability, increased blood pressure.

The inconvenience that such vibrations cause has not yet been physiologically explained.

However, it is known that they act on cells located at the level of the inner ear, the so-called cochlea. High-pitched sounds seem especially shrill to us, as they almost always come from the background noise. This is why the alarm signals are at very high frequencies. On the other hand, low sounds, characteristic engine noises or "techno" music not only irritate the auditory cells - they make our soft organs vibrate. The shoulder blades, heart and intestines resonate and produce an almost tactile sensation of sound.

But if the sound drives you crazy, then more often because of its high volume. The more powerful the sound, the more molecules move through the air as the sound wave propagates.

When moving back and forth, comparable to the movement of concentric waves after a stone falls into water, the air vibrates for various reasons. And it puts a lot of pressure on the ear.

The auditory sensation resulting from the transformation of sound by our ear and our brain, a sound wave into an unequal emission, becomes frankly unpleasant.

If the auditory system allows you to hear sounds from 0 to 140 dB, pain starts at 120 dB. A feeling of discomfort, rather subjective, appears already at 60 dB (car, street noise).

If the sound is strong, especially very low or very high, it affects the whole organism. The heart rate and breathing speed up, causing pulsations and an increase in pressure. The neuromuscular system is also affected. Convulsions and spasms. From the noise in the literal sense "breaks the bones." The thyroid and adrenal glands are also affected, which contributes to stress and sleep disturbance. Increases sweating. In exceptional cases, the pupils dilate, disrupting the perception of color and narrowing the field of vision. With noise it is very difficult to think, as the concentration of attention is disturbed.

The sensation of noise also depends on its duration. A shot or hammer blow makes you flinch at the high sound level, but mostly because of the brevity of the sound.

Such impulse noises can damage the auditory cells of the inner ear. They are very short and do not allow the ear to activate the protective system. This reflex works by contracting the muscles in the middle ear, limiting exposure to outside sounds, so short noises can be deafening.

Some noises increase our irritation, such as a whistle, which is short, sharp and disturbing. Musicians know these features well. These are sounds whose frequency components are very close. The sound seems "rough", as if the piano gave a chord of two consecutive notes in a chromatic scale, for example, C and sharp. A saw, a sports car engine, or the squeaking of chalk on a blackboard contain many of these annoying sounds.

Frequency, strength, duration...

This explosive cocktail is a potentially dangerous weapon for both hearing and the whole body.

Decibels cause euphoria

At first, a very high sound level makes ravers more receptive to music, isolating them from the outside world. This impact is enhanced by the repetitive structure of the passage, which "lulls" conscious brain activity and allows you to escape from reality. Loud music can be euphoric like a drug, leading, as happens at rock concerts, to a state of collective hysteria. And just like a drug, it is addictive and addictive. The same exciting effect is used at rock concerts and discos stroboscopic effects - a rapid alternation of flashes of bright light. By the way, a stroboscope is used in neurological studies when a patient is suspected of having epilepsy. Stroboscopic effects may even cause her to have an attack. As a rule, the action of loud music and the stroboscopic effect is summed up.

The low ones get knocked out

The ears of techno lovers get used to the sound stream. But the body continues to be affected: an acceleration of the heart rate, muscle contractions, even hormonal disorders. Their digestive system is upset by the dominant low sounds, causing severe ailments.

Harmful are not only those sounds that we hear, but also those whose frequency the human ear does not register. Infrasounds, that is, sounds of very low frequency, interacting with the energy-informational vibrations of the central nervous system, cause a feeling of lethargy, drowsiness, followed by sometimes opposite reactions - aggressiveness.

For example, those women who listened to hard rock during feeding lost milk, while those who preferred the classics increased it by 20%. Also, with the help of sounds, it is possible to control the crowd. There is such an assumption that the missing ship crews were affected by infrasound, people were controlled by fear, and they jumped from the sides of the ship. Today, scientific studies have proven that such sounds as in vitro and in vivo of a certain frequency kill viruses. And the purring of a cat has a good effect on the human psyche.

The vibrations that the ear perceives stimulate the nerves in the inner ear, where the vibrations are converted into electrical impulses and then sent directly to the brain. Many sounds pass into the auditory centers, they are perceived as sounds. The rest is converted into electrical potential in the cerebellum, which controls movement and balance. Then they enter the limbic system, which is responsible for emotions and the release of hormones that affect the entire body. This is how sound feeds the brain and our body.

Subconscious suggestion through music is the best method of controlling the human psyche. Music, bypassing consciousness, is able to penetrate the subconscious and program it. After experiments, it was proved that due to the suggestion "do not steal" in supermarkets, the number of thefts was greatly reduced. Playing certain songs continuously has saved store owners millions of dollars. Relaxing music recreates a cozy homely atmosphere in the supermarket, and forces customers to take their time, devoting a lot of time to shopping. At rush hour, fast music is used, which provokes buyers to move much faster. A similar method is used in restaurants, a specially trained manager continuously monitors visitors in the hall. If there are too many, dynamic recordings are turned on, if there are few visitors, relaxing music is put on in order to keep customers in the restaurant longer.

Sound therapy is the use of music for healing purposes. Sound therapy has been an independent branch of traditional medicine since ancient times. Even ancient philosophers such as Pythagoras, Aristotle, Plato knew that sounds and music are able to restore the original harmony of the soul broken by illnesses. In his famous work The Kreutzer Sonata, L. Tolstoy applied a special hypnotizing effect to music. Tsiolkovsky also believed that music is "a powerful tool, like medicines", which, accordingly, should be in the power of specialists. Aesculapius, a famous Greek physician of antiquity, treated sciatica and various diseases of the nervous system by playing the trumpet loudly in front of the patient. Pythagoras began and ended his day with singing (in the morning - to clear the mind and excite activity, and in the evening - to calm and attune to rest).

According to neuroscientist Jevasia Schreckenberger and physicist Harvey Byrd, rhythmic and loud music weakens the human body. They conducted experiments on mice, watching two groups of them looking for food in the labyrinths built for them. During this process, some listened to Strauss waltzes, while others listened to drumming. As a result, it turned out that those who were searching for waltzes began to navigate the maze better, and those who did it to the sound of a drum, even after three weeks, could not find their way to food. So, a noticeable deviation in the development of hippocampal neurons (part of the limbic system of the brain, the olfactory brain, is involved in the mechanisms of the formation of emotions, memory consolidation) was revealed, which made it very difficult for mice to come to prey.

Usually, noise violates the logic of thinking, leads to uncertainty and irritability. In order to isolate oneself from such harmful noises, a correct understanding of the influence of music and sounds in general on a living organism is necessary. To unload the nervous system, it is useful from time to time to take a break from all the noise. Turn off the phone, electrical appliances and remove the headphones for at least 20 minutes and stay in complete silence. It is better to lie down at this time, try to relax as much as possible, and the body will begin to recover faster.

If you have any hearing impairment, you should immediately contact an otolaryngologist.

The impact of noise on a person depends on the noise level, its characteristics and spectrum, exposure time, resonance phenomena. It also depends on the state of health, the adaptability of the body, the individual characteristics of the person and other factors.

The unpleasant effect of noise affects the emotional mood, motivation of actions, initiative, maybe, but, as a rule, does not manifest itself in the deterioration of work; in any case, it causes inconvenience to a person.

The disturbing effect of noise adversely affects the work of a person in that it causes strong concomitant irritations that negatively affect the main work of a person; increases the workload.

The harmful effects of noise cause pathological changes in the organ of hearing, worsen the state of the nervous system and the whole organism as a whole. It has a negative effect on certain types of human activity associated with changing certain situations, long-term management work and unforeseen reception of information that require attention. Short-term mental and physical activity is essentially independent of uniform exposure to noise of high intensity or high frequency.

Noise distracts a person's attention and thus has a negative effect in cases where it is necessary to monitor the flow of information or random changes.

Strong industrial noise adversely affects the human body. It reduces his working capacity, labor productivity, increases the susceptibility to heart attacks, increases the likelihood of neuroses and nervous diseases, worsens eyesight, causes headaches, mental depression, fatigue, causes a decrease in attention and psychological focus on work and an increase in reaction time. Noise disrupts relationships between people, a calm working environment. It causes a sharp deterioration in health in certain types of diseases, nervousness, a tendency to conflict situations. The unpleasant effects of noise have a stronger effect on mental than physical work.

According to the studies of E. Weil (France), exposure to strong noise causes the following mental disorders: disorders of the nervous system and the system of internal secretion, changes in the instinct of self-preservation, intellectual degeneration and inability to self-control, unwillingness to work, disturbance of a balanced state, conflicts between workers based on mental irritation.

The noise is more unpleasant, the narrower the frequency band and the higher the intensity. Noise, which has high tones in its composition, has the most harmful effect.

Noise above 500 Hz is more disturbing (error causing) than lower frequency noise. Intermittent chaotic noise is more harmful than constant noise. Noise with variable intensity (eg 40-70 dB) is more harmful than sound with constant intensity (eg 80 dB).

Unexpectedly occurring intense noise and sound (for example, impact) are very dangerous and have a significant impact on the decrease in productivity.

Rhythmically fluctuating and stepped noise, hissing, thunder and creaking can be unpleasant; they reduce the ability to perform coordinated movements quickly and accurately.

Strong noise causes difficulties in estimating distance and time, in recognizing color signals, reduces the speed of color perception, visual acuity, visual reaction at night, and disrupts the perception of visual information.

Labor productivity decreases by 5-12%. By reducing the noise level by 20%, it is possible to achieve an increase in labor productivity by 5-10%. Prolonged exposure to noise with an intensity of about 90 dB reduces labor productivity by 30-60%.

Monotonous monotonous sound or noise causes fatigue and increases the feeling of monotony. Noise and signaling sounds such as telephone ringing, loudspeaker sound, etc. interfere with operation.

Production noise, especially associated with pleasant and necessary work, is perceived normally and does not irritate. The worker, as a rule, is not annoyed by the noise of his own machine, but is annoyed by unpleasant, uncontrollable noise that appears unexpectedly from other machines.

A person aged 20-40 years tolerates strong noise worse than a person older or younger than this age, women tolerate noise better than men. People suffering from hypertension tolerate loud noise worse than healthy people.

A person does not perceive the normal noise of the living space. He just needs it. A quiet and noiseless environment negatively affects the human psyche, since absolute silence is not habitual for a person.

Rice. 1. Human exposure to noise

Noise levels are given and not included!. noe, interfering and harmful effects on the body of a working person, on his thinking, actions, on the reception of information and a decrease in labor productivity.

- Impact of noise on humans

Noise has recently become a real disaster for big cities.

The impact of noise on a person is a health factor photoAnd this is not even surprising, since with the development of industry and technology, a lot of computers appeared in offices, in the shops of the latest equipment, and the roads of large cities are teeming with cars hurrying somewhere. The fact that noise adversely affects human health has long been proven. But unfortunately, not everyone understands what consequences the constant influence of noise on a person can lead to.

What is noise and what is its impact on health?

They can designate any sounds that interfere with the perception of useful signals, these are sounds that have an irritating and harmful effect. If you look at noise as a physical phenomenon, then we can say that these are wave vibrations of solid bodies, of various frequencies and intensities. A person is able to hear vibrations, the frequency of which is 16-20000 Hz.

Why is noise so bad? Effects of noise on health, of course, depends on how long a person is under its influence, on the intensity of sounds and their periodicity. It has been proven that even not intense, but constant sounds have a more harmful effect. Infrasound is very dangerous, which a person does not even feel. Sounds with a range of 3-5 Hz can cause anxiety, pain in the head and spine. All this happens because the sounds of such a range coincide with the frequency resonance of the human body. In general, the harm caused by noise in large cities can only be compared with the negative impact that a polluted city has on people.

Impact of noise on human health can be different - from simple irritation to serious pathological diseases of all internal organs and systems. First of all, of course, human hearing suffers. The volume level and frequency of noise effects directly affects the development of hearing loss. The disease develops gradually, so it is necessary to protect yourself from this irritant in advance. Due to the strong high-frequency sound, pathological and irreversible changes occur in the auditory organs.

Harmful effects of noise is not limited to the effect only on the organs of hearing. An increased noise stimulus negatively affects the human nervous system, the cardiovascular system, and causes severe irritation. Excessive noise can cause insomnia, fatigue, aggressiveness, affect reproductive function and contribute to serious mental disorders.

Even small sound levels, from 40 to 70 dBA, have a harmful effect on a person. Exist permissible noise levels, which reflect the acceptable noise level during work and at home.

If we consider the factors affecting human health in large cities, then noise has perhaps the most important negative impact on human health. To protect against the harmful effects of noise, it is necessary to strictly regulate its duration, spectral composition, intensity and other characteristics. This is the goal of sanitary and hygienic institutions.

It is unfortunate, but today, due to the negative impact of noise irritant, many people seek help from medical institutions and buy medicines. And these diseases are not only of a nervous nature, noise contributes to the development of other serious diseases.

The permissible noise level can be called the one that does not adversely affect the physiological functions of the human body. If noise causes irritation, headaches and hearing impairment, then this must be dealt with. Install soundproofing at home, check the level of noise irritant at the workplace and contact the management of the enterprise, as well as an online pharmacy will help you quickly deliver headache medications to your home.