Noise - a slow killer, as well as chemical poisoning. The first extant complaints of noise can be found in the Roman satirist Juvenal (60-127 gg.).
Modern noise causes discomfort in livingorganisms painful reactions. Noise from flying jet plane, for example, a depressing effect on the bees, it loses the ability to focus. The same noise kills bee larvae, breaks open the egg laying birds in the nest. The transport or industrial noise depressing person - tired, annoyed, distracted by. Once such a noise ceases, the person feels a sense of relief and peace.
Let correlate decibels and types of noise:
102 dB - jet long-range landing (1500 m from the runway end)
98 decibels - a jet plane taking off on medium-range (1500 m after the runway lift)
107 decibels - a car horn at a distance of 7.5 m
102 dB - an express train at a speed of 140 km / h at a distance of 25 m
91 decibels - the bus at a distance of 7.5 m
86 decibels - the motorcycle at a distance of 7.5 m
The noise level of 20-30 decibels (dB) is practicallyharmless to humans. This is the natural background noise, without which human life is impossible. For the "loud noises" about the permissible limit of 80 decibel sound at 130 decibels is already causing a person a feeling of pain, and in 150 - it becomes unbearable for him. The sound of 180 decibels causes metal fatigue, and at 190 rivets are pulled out of the designs. Not without reason in the Middle Ages there was a penalty "under the bell". Ringing bells slowly killing the person.
Any noise of sufficient intensity and duration can lead to varying degrees of reduction of the auditory activity.
Noise and related factors
In addition the frequency and volume of noise level atthe development of hearing loss affect age, hearing sensitivity, duration and nature of the action of noise, a number of other reasons. The disease develops gradually, so it is particularly important in advance to take appropriate measures to protect against noise. Under the influence of strong noise, especially high frequency, in the organ of hearing irreversible changes. At high levels of noise reduction in hearing sensitivity occurs after 1-2 years of work, at medium levels, it is found much later, in 5-10 years.
As we lose hearing
The sequence with which the loss ofhearing, it is now well understood. First, intense noise cause temporary hearing loss. Under normal conditions, a day or two hearing restored. But if noise exposure continues for months or, as is the case in the industry, over the years, the recovery does not occur, and the temporary threshold shift is converted to DC.
First, nerve damage affectsperception of high-frequency range of sound vibrations (4 th. Hz or higher), gradually extending to the lower frequencies. High sounds "p" and "s" are inaudible.
The nerve cells of the inner ear are damaged so that the atrophy, die, are not restored.
Noisy music also dulls hearing. A team of specialists surveyed young people often listen to trendy modern music. In 20 per cent of boys and girls rumor appeared in obtuse extent, as 85-year old.
Noise interferes with normal rest and recoveryforces disrupts sleep. The systematic lack of sleep and insomnia lead to serious nervous disorders. Therefore, the protection of sleep - this "balm of the soul" - from all sorts of stimuli should be given great attention.
Noise has a detrimental effect on the visual andvestibular analyzers, reduces the stability of a clear vision and reflex activity. Noise increases the number of all kinds of diseases and more because it is a depressing effect on the psyche, it contributes to a significant expenditure of nervous energy, causing emotional contentment and not protest.
Studies have shown that inaudible soundsalso dangerous. Ultrasound, which occupies a prominent place in the scale of industrial noise that adversely affects the body, even though his ear does not perceive. airplane passengers often feel a state of malaise and anxiety, one of the reasons is that infrasound. Infrasound cause some people motion sickness attacks.
Even weak infrasound can have onHuman significant impact if they are long-term in nature. Some neurological diseases peculiar to the inhabitants of industrial cities, it is caused by infrasound, penetrate the thickest walls.