To feel comfortable and peaceful, a person does not need absolute silence. The complete absence of sounds will not bring peace of mind, and such a state of the environment is not silence (in the usual sense of the word). A world filled with barely perceptible, often not perceived by the consciousness rustles and midtones allows you to relax from the noise and bustle of the mind and body. However, many sounds of different strengths and beauty fill the lives of people, bringing joy, delivering information, simply accompanying the necessary actions.
How to understand that having fun does not interfere with others and do not harm yourself? How to eliminate annoying and negative influence from the outside? For this, it is useful to know and understand scientifically established noise level standards.
What is noise
Noise is a physical and multi-valued quantity (for example, digital noise in images). In modern science, this term refers to non-periodic oscillations of a different nature - sound, radio, electromagnetic. Before in science, only sound waves were included in this concept, but then it became wider.
Most often, noise means a complex of irregular sounds of different frequencies and heights, and from the point of view of physiology, any unfavorably perceived acoustic phenomenon.
Noise unit
Measure the noise level in decibels. A decibel is a tenth of a protein that is practically not used. It characterizes the relationship to each other of the same two physical (energy or power) quantities - that is, power to power, current to current. One of the indicators is taken as the initial one. It can be simply reference or generally accepted and then they talk about the level of the phenomenon (an example is the power level).
For those uninformed in mathematics, it will be clearer that the fact that raising any initial value by 10 dB for the human ear means twice as loud a sound as the initial one, by 20 dB - four times, and so on. It turns out that the quietest sound heard by a person is a billion times weaker than the loudest. The use of such a designation greatly simplifies the recording, eliminating the multitude of zeros, and facilitates the perception of information.
Bel originates from the methods used to assess the attenuation of telephone and telegraph signals in the respective transmission lines. It is named after the American scientist of Canadian origin Alexander Graham Bell, one of the pioneers of telephony, the author of many inventions and the founder of the currently largest in the world media conglomerate American Telephone and Telegraph Company, as well as a major research center Bell Laboratories.
The ratio of numbers and life phenomena
To understand the numerical expression of the noise level, you need to have precise guidelines. Without application to familiar life phenomena, numbers will remain abstract signs.
| Sound source | Decibel value |
|---|---|
| Calm normal breathing | ten |
| Rustling foliage | 17 |
| Whisper / leafing | 20 |
| Quiet noise background in nature | thirty |
| Quiet (normal) noise background in an urban apartment building, the sound of waves of a calm sea rolling on the shore | 40 |
| Calm conversation | 50 |
| Sounds in the premises of a not very large office, restaurant hall, rather loud conversation | 60 |
| The most common sound level of a working TV, the noise of a busy highway from a distance of ~ 15.5 meters, loud speech | 70 |
| A working vacuum cleaner, a factory (feeling outside), a subway train (from a car), elevated conversation, crying for children | 80 |
| Working lawn mower, motorcycle from a distance of ~ 8 meters | 90 |
| Driving motor boat, jackhammer, active traffic | 100 |
| Loud screaming baby | 105 |
| Heavy music concert, thunderous roll, steel mill, jet engine (from a distance of 1 km), train in the subway (from the platform) | 110 |
| The loudest recorded snoring | 112 |
| Pain threshold: chain saw, shots from some guns, a jet engine, a car horn near | 120 |
| Car without a silencer | 120-150 |
| Fighter taking off from an aircraft carrier (in the distance) | 130-150 |
| Working punch (in the immediate vicinity) | 140 |
| Rocket launch | 145 |
| Supersonic Aircraft - Shock Sound Wave | 160 |
| Deadly level: powerful volcanic release | 180 |
| 122 mm artillery shot | 183 |
| The loudest blue whale | 189 |
| Nuclear explosion | 200 |
The effect of noise on the human body
The negative effects of noise on people have been confirmed by many studies. In ecology, the very eloquent concept of “noise pollution” has even formed.
Noise level above 70 dB with long-term exposure is likely to cause disorders of the central nervous system, drops in blood pressure, headaches, metabolic disorders, malfunctions of the thyroid gland and digestive organs, impairs memory, ability to concentrate and, of course, reduces hearing. Noise in excess of 100 dB can lead to absolute deafness. Intense and prolonged exposure can provoke a rupture of the eardrum.
An increase in average noise for every 10 dB raises blood pressure by 1.5-2 mmHg, while the risk of getting a stroke increases by 10%. The noise leads to earlier aging, reducing the lives of large cities by 8-12 years. According to experts, the permissible noise level in megacities is significantly exceeded: by 10-20 dB near iron and by 20-25 dB near medium roads, by 30-35 dB in apartments whose windows are not soundproofed and open onto large highways.
World Health Organization research has shown that 2% of all human deaths are due to diseases caused by excessive noise. The danger is also those sounds that are not perceived by the human ear - lower or higher than a person is able to hear. The degree of exposure depends on their strength and duration.
Daytime noise levels
In addition to federal laws and sanitary rules, it is possible to adopt local laws that tighten national regulations. Russian law provides for noise level restrictions that differ during the day and night, as well as on weekdays and weekends / holidays.
On weekdays, there will be a period from 7.00 to 23.00 - noise up to 40 dB is allowed (a maximum of 15 dB is permissible).
From 13.00 to 15.00 the noise level in the apartment should be minimal (complete silence is recommended) - this is the official afternoon rest time.
On weekends and holidays, the schedule changes a little - daily rates are valid from 10.00 to 22.00.
Repair work in residential apartment buildings is permitted only on weekdays in the period from 9.00 to 19.00 with a mandatory hour break for lunch (in addition to complete silence from 13.00 to 15.00), and their total duration should not exceed 6 hours. Complete repairs in the apartment should be within 3 months.
The following international standards are recommended for workplaces:
- industrial premises - noise level up to 70 dB;
- open offices (partitions between workstations do not reach the ceiling) - up to 45 dB;
- closed offices - up to 40 dB;
- conference rooms - up to 35 dB.
Is it possible to make noise at night?
During sleep, the auditory sensitivity of a person increases by almost 15 dB. According to the World Health Organization, people become irritable if they are affected by sounds of only 35 dB in a dream, noise of 42 dB leads to insomnia, and diseases of the cardiovascular system from 50 dB.
The night time on weekdays is considered part of the day from 23.00 to 7.00, on weekends and holidays from 22.00 to 10.00. Noise level should not be more than 30 dB (permissible excess of a maximum of 15 dB).
In exceptional cases, violation of established norms is allowed, these include:
- capture of criminals;
- actions taken in cases of force majeure, during emergency situations and natural disasters, as well as to eliminate their consequences;
- holding citywide celebrations with the launch of fireworks, concerts.
Noise measurement
Is it possible to independently determine the amount of dB? It is very easy to determine the noise level yourself, without having professional devices. To do this, you can:
- apply a special program for the computer;
- Install the appropriate mobile application on the phone.
True, the results of these measurements will turn out to be used only for personal needs.
For a more accurate study, it is better to use the technique designed for this - a sound level meter (often it can also be found under the name "sound level meter"). However, if you need to prove a violation of the rules for official proceedings, you will have to call a specialist with the same device.
There are sound level meters of 4 classes of accuracy and, accordingly, cost.
In order to most accurately determine what noise level is in the measurement area, it must be taken into account that the device should not be used at temperatures below -10 ° C and above +50 ° C. Humidity in the room should not exceed 90%, and atmospheric pressure should be outside the limits of 645 to 810 millimeters of mercury.
Where to go if you need to measure noise
Measurements can be carried out by representatives of forensic organizations, but only on the basis of a court order. The research is carried out by representatives of Rospotrebnadzor or third-party organizations accredited by it for this activity. Design organizations, members of builder organizations working on the principles of self-regulation (SRO) will help - for the legitimate activities of construction companies, joining such non-profit associations is a prerequisite.
