Noise is a chaotic mixture of sounds of different frequencies and intensities, which can make people distracted and difficult to work and rest at ease. Long-term exposure to high-intensity noise not only damages the auditory organs, but also affects the central nervous system, cardiovascular system, endocrine system and digestive system to varying degrees. Common symptoms include auditory fatigue, hearing loss, tinnitus, and vocal cord aging. The diagnosis of noise-induced effects on the external auditory system should be made with special care, and the effects of inherent diseases and other harmful occupational and environmental factors must be excluded. 3, hearing examination, permanent hearing threshold displacement beyond the normal range, the speech frequency hearing is still in the normal range, but 3000, 4000, 6000Hz high frequency pure tone audiometry in any frequency hearing loss ≥ 30dB, the diagnosis of hearing impairment, as hearing protection as an observation; on the basis of high frequency hearing loss, found 500, 1000, 2000Hz speech frequency hearing loss in any of the three frequencies of the hearing impairment, as a hearing protection as an observation object; on the basis of high frequency hearing loss, found 500, 1000, 2000Hz speech frequency hearing loss. 2000Hz speech frequency on the basis of hearing loss, the average value of the sum of the three hearing loss ≥ 25dB, the diagnosis of noise deafness, China has not yet officially announced the grading standards for occupational noise deafness, the proposed classification principles are: hearing loss 25-40dB for mild deafness; 41-55dB for moderate deafness; 56-70dB for severe deafness; 71-90dB for severe deafness; > 90dB for total deafness.