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Noise

The ability to perceive sounds is vitally important for life and communication, but not all sounds are desirable to hear.

Sound is generated from mechanical vibrations that occur when a particle in the environment (gas, liquid, solid) comes into contact with another force in the environment. Vibrations from the sound source are distributed in the form of elastic waves — similar to the way in which a loudspeaker membrane disseminates sound.

While sound is an essential component of life, too much or too little sound can cause mental disorders. Many factories that produce air-conditioning units have specially built testing chambers that extinguish all sound coming from both outside and inside. These chambers are used to test the equipment in order to understand what kind of noises it produces. When the rooms are being shown to visitors, the doors are left open so that people elsewhere in the factory can be heard, as being left alone in complete silence can cause severe distress.

The power of sound is measured in decibels (dB). The rustle of leaves in the trees produces about 20 dB, a quiet office environment is around 40 dB, a relatively noisy office between 50 and 60 dB, traffic or a noisy restaurant 75 to 80 dB, a jackhammer or rock concert between 100 and 120 dB, and a plane taking off between 130 and 140 dB. A sound of the latter’s magnitude can cause physical pain, and more intense sounds can cause shock or concussion, or even lead to death.


Excessive noise is harmful to humans:

  • Noise is a common cause of human sleep disturbance. Random noises such as flying aircraft or car traffic louder than 55 dB will wake most sleepers.
  • Noise above 35 dB also impedes communication, and conversation is impossible when noise levels exceed 70 dB.


Noise has negative physical and mental effects:

  • Noise typically has an impact on physical health and can lead to physiological stress. Excessive noise levels affect the human nervous system, leading to heightened stress levels, which in turn affect behaviour and activity.
  • Noise can cause irritation and aggression, increased blood pressure, tinnitus and hearing loss. Regular exposure to noises of 70 to 80 dB (e.g. the hum of a nearby motorway) can make people tired and irritable. A subsequent rise in blood pressure decreases working capacity; fatigue becomes chronic and can develop into insomnia, after which various neuroses can emerge. Constant exposure to noise levels above 90 dB can impair hearing. At 100 dB, noise can have a disorienting effect and exposure to noise of over 110 dB can lead to the same kind of intoxication as that produced by alcohol or drugs. The human eardrum will burst when exposed to noise at a level of 145 dB.
  • Scientists still do not fully understand how noise affects other living organisms.
  • Noise levels also have an economic impact. The presence of significant sources of noise in the vicinity decreases the value of real estate. Illness and discomfort caused by noise affects productivity and increases the number of accidents caused by lack of sleep.


Studies have shown that in Europe:

  • 65 percent of the population (about 450 million people) are exposed to levels of noise over 55 dB for periods of 24 hours or longer, which cause irritability and anxiety.
  • 17 percent of Europeans (about 113 million people) are regularly exposed to noise levels of at least 65 dB, which seriously affect health.
  • Approximately 10 million people are regularly exposed to levels of 75 dB during the day.

In Belarus, more than 30 percent of citizens are exposed to noise levels of 55 to 65 dB on an everyday basis:

  • Noise levels in cities are two to three times higher than average levels in the country. Ideally, noise in open areas should not exceed 65 dB during the day, and noise levels in areas where there are new buildings should not be higher than 55 dB.
  • Vehicles (cars, trains etc.) are the main sources of noise. The movement of vehicles on roads is the greatest source of noise levels over 55 dB. Noise increases in recent years are due to the rapid growth in the number of vehicles. At speeds of 40 km/h and higher, the sound of a car’s tyres moving along the surface of a road can drown out engine noise.
  • Exposure to noise from air transportation is far lower than to noise from other kinds of vehicles. Despite the fact that the number of flights has grown steadily in recent decades, new technologies have significantly reduced aircraft noise.


Aside from vehicles (which are responsible for 60 to 80 percent of all noise), other sources include factories, construction work, car alarms, barking dogs and noisy people:

  • Industrial activities — from small workshops to heavy industrial plants — often produce noises of 55 dB and higher, which is loud enough to cause anxiety and stress or to seriously affect a person's emotional state.
  • Public recreation and entertainment venues, such as stadiums and sports centres, parks, discotheques and rock concerts, produce a lot of noise. Newly popular forms of entertainment, such as motorcycling, off-road racing and water skiing, also generate lots of noise.
  • In the streets, complaints are often made about barking dogs or loud music.
  • Poor city planning (e.g. the construction of an airport within city limits) can lead to excessive noise in residential areas.
  • Indoor environments often feature equipment and machinery that produce high levels of noise.


Measures can be taken to reduce noise levels:

  • Terrain, potential sources of noise and other key factors should be taken into consideration during the design stage of a project in order to identify ways to reduce or eliminate excessive noise. The construction of anti-noise barriers alongside roads is one example.
  • Where little or nothing can be done about external noise, solutions may be available at household level, including the installation of soundproofing or double-glazed windows.


According to current health rules and norms, the permissible noise levels in residential buildings are up to 40 dB during the day and up to 30 dB at night. These levels were calculated taking into account physiological and health studies, as well as long-term observations and international datasets. The dimensions of buffer zones for railway lines are determined on an individual basis using calculations of physical effects as described in the official publication Requirements for the Organisation of Sanitary Protection Zones for Enterprises, Buildings and Other Objects That Are Subject to Impacts on Human Health and the Environment.



Levels of noise
Noise pollution