环境噪声危害（Environmental noise hazard）.docVIP

环境噪声危害（Environmental noise hazard） Noise pollution is harmful to people, animals, instruments and meters and buildings, and the degree of harm mainly depends on the frequency, intensity and exposure time of noise. Noise hazards mainly include: Noise damage to hearing The most direct harm to human body is hearing damage. People in the strong noise environment, exposed for a period of time, will feel uncomfortable ears, very much noise pollution noise pollution To have a headache and so on. When you leave the noise environment and rest in a quiet place for a while, your hearing will gradually return to normal. This phenomenon is called temporary threshold shift, also known as auditory fatigue. However, if people working in strong noise environment, auditory fatigue can not get timely recovery, and the inner ear organs organic lesions, which form a permanent threshold shift, also known as noise induced deafness. If a person suddenly exposed to noise is extremely strong in auditory organs increases dramatically due to trauma, tympanic membrane rupture, lost bleeding, screw from the basement membrane of acute dissection, may make the ear completely lost the hearing, namely blast deafness. [1] If there is no protection work in a strong noise environment, after leaving the noise environment, the recovery of auditory sensitivity will be prolonged, and after a few hours or more than ten hours, the hearing can be restored. This loss of hearing recovery is called hearing fatigue. With the aggravation of hearing fatigue, the hearing function will be restored. Therefore, to prevent noise deafness, first of all to prevent fatigue. Under normal circumstances, 85 decibels of noise will not harm the hearing, and more than 85 decibels may be dangerous. Statistics show that long-term work in more than 90 decibels in the noise environment, the incidence of deafness increased significantly. Noise can cause many diseases Because noise affects the central nervous system of the brain throu