Noise - a chaotic combination of different strength andfrequency sounds; may adversely affect the organism. In recent years, due to the significant development of public transport has increased the intensity of noise and in the home, so as an unfavorable factor he acquired great social importance.
Prolonged exposure to intense noise (above 80dB) for human hearing it leads to partial or complete loss. Depending on the duration and intensity of exposure to noise takes place more or less decline in hearing sensitivity, which disappears after exposure to noise, and when long duration and (or) the noise intensity irreversible hearing loss (deafness), characterized by a constant change in the threshold of hearing.
There are the following degrees of hearing loss:
- Grade I (mild hearing loss) - hearing loss in speech frequencies of 10 - 20 dB at a frequency of 4000 Hz - 20 - 60 dB;
- Grade II (mild hearing loss) - hearing loss in speech frequencies of 21 - 30 dB at a frequency of 4000 Hz - 20 - 65 dB;
- Grade III (a significant hearing loss) - hearing loss in speech frequencies is 31 dB or more at a frequency of 4000 Hz - 20 - 78 dB.
Noise destroys not only hearing
Noise effect on the human organism is notlimited impact on the organ of hearing. Through auditory nerve fiber irritation of noise transmitted to the central nervous system, and through it affects the internal organs, leading to significant changes in the functional state of the body, it affects the mental state of a person, causing anxiety and irritation. Man is exposed to intense (more than 80 dB) of noise, it spends an average of 10 - 20% more than the physical and neuro-psychiatric efforts to maintain the rhythm of the work, achieved by the sound at a level below 70 dB (A). The most pronounced is a violation of the peripheral circulation due to narrowing of the capillaries of the skin and mucous membranes, as well as high blood pressure (with sound levels above 85 dBA).
At irregular pulse and the noise level of the noise exposure increases.
What is the "noise disease"
At the present time "noise disease" is characterized by a complex of symptoms:
- decrease in hearing sensitivity;
- changes in digestive function, which is expressed in low acidity;
- heart failure;
- disorders of the nervous and endocrine systems.
Ultrasounds (above 20,000 Hz) also arecause hearing damage, although the human ear does not respond. Powerful ultrasound acts on nerve cells in the brain and spinal cord, causing a burning sensation in the ear canal and the feeling of nausea.
They are no less dangerous infrasonicinfluence of the acoustic oscillations (less than 20 Hz). With sufficient intensity infrasound can affect the vestibular system, reducing auditory sensitivity and increasing fatigue and irritability, and lead to the coordination of infringement. A special role is played infrachastotnye oscillations with a frequency of 7 Hz. As a result of their match with the natural frequency of alpha - brain rhythms are observed not only hearing impairment, but there may be internal bleeding.
A special place in the organ of hearing pathology occupylesions caused by exposure to ultra-intense noises and sounds. Their short-term action can cause total loss of the spiral body and the eardrum, accompanied by a feeling of fullness and sharp pain in the ears. The end result of barotrauma is often a complete loss of hearing. In a production environment, such cases are extremely rare, mainly in emergency situations or explosions.
If you notice golovnauyu pain, feeling of heavinessand noise in the head, resulting in the end of a shift or after work, dizziness when changing body position, increased irritability, fatigue, decreased ability to work, attention, increased sweating, especially when unrest, sleep disturbances of rhythm (daytime sleepiness, disturbed sleep at night ) - it's time zudmatsya about the noise of the disease.