For residents of noise - business as usual. Quite often people do not even think about it unnatural. In any region of noisy vehicles, tram rumbles with some noise of the enterprise, taking off from the airfield near the aircraft. In apartments noisy refrigerators and washing machines, in the entrances - elevators. The list goes on. If the noise is so much in our lives, it may seem that it is harmless. However, their impact on the human noise more harmful than chemical pollution. Over the past 30 years in all major cities of noise increased by 12-15 dB, and the subjective loudness increased by 3-4 times. Noise reduced productivity by 15-20%, significantly increased the incidence. Experts believe that in big cities noise reduces life by 8-12 years.
The frequency of diseases of the cardiovascular system in people who live in noisy areas several times higher, and coronary heart disease they occur three times more often. Also increasing the overall incidence.
Particularly impressive noise impact on local residents. If the 100,000 rural residents account for 20-30 people who do not hear, the cities, the figure grows by 5 times. According to statistics, residents of large cities lose hearing acuity since 30 years (in normal - 2 times later). Under the influence of noise worsens sleep and receptivity to learning. Children become more aggressive and capricious.
To indicate the combined effect of noise on human doctors introduced the term - "noise disease." The symptoms of this disease are headache, nausea, irritability that is often accompanied by temporary hearing loss. To the noise of the disease tend to most urban residents who are constantly getting noise load. For example, the standard noise level in dB for residents of neighborhoods should be 55 during the day and 45 at night. However, various sources of anthropogenic noise making a significant contribution to the sound environment of the city. In modern urban areas with significant traffic noise close to a dangerous limit of 80 dB.
Noise effect on the human body not only directly and indirectly. Noise has other possible influences. Thus, in urban life trees shorter than in rural areas. The main reason for this is the impact of intense noise. The action noise of 100 dB plants survive 10 days. In this rapidly dying flowers and slow plant growth.
Thus, the noise is harmful, but if you can reduce its impact on living organisms, including humans? It turns out that possibly many such events. First you need to comply strictly with applicable regulations. Today on the streets of big cities noise down below 80 dB. In order to reduce this level Considerable efforts primarily on the improvement of the technology. Designers working on Quiet engines and vehicles, residential buildings move away from street lines, the last separated from buildings concrete screens, improve coverage.
Effective measures to combat noise in cities is gardening. Trees that are planted close to each other, surrounded by thick bushes, significantly reduce the level of man-made noise and improve the urban environment.
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The negative physical factors of the city belongs to the vibration. The sources of vibration in the cities are: rail transport, road transport, construction machinery, industrial plants.
Usually the vibration spreads from its source to a distance of 100 m the most powerful source of vibration - rail. Fluctuations in soil near the railroad exceed an earthquake measuring 6.7 points. In Metro intense vibration applied to 50-70 m
Adversely affect the human body and electromagnetic radiation power frequency (50 Hz) and frequency radiowave range. In rooms electromagnetic fields pose: radios, TVs, refrigerators, etc., that is a danger. If there is a constant source of electromagnetic radiation, which works in a similar (or is a multiple) frequency, which can lead to an increase or decrease in normal frequency of the human body, then the consequence can be a headache, sleep disturbance, fatigue, even the threat of angina. The most dangerous radiation is when a person (especially a child) sleeps.
Of course, do without electrical appliances impossible and unnecessary. The main thing - to follow certain rules:
Ø in the bedroom is not set computer, "base" for cordless phones, as well as starting the night devices for recharging batteries and accumulators;
Ø TV, stereo, VCR should turn off at night from the grid;
Ø electronic alarm should not stand in their heads;
Ø power microwave ovens may vary, so from time to time, one must go to the master to control the level of radiation.
