Hearing loss, noise-induced.
Preventing occupational disease and injury, second edition. Levy BS, Wagner GR, Rest KM, Weeks JL, eds. Washington, DC: American Public Health Association, 2005 Jan; :223-231
Noise-induced hearing loss is one of the most common occupational illnesses in the United States. It is characterized by a gradual worsening of high-frequency hearing thresholds over time following chronic and sometimes acute exposure to excessive noise levels. Figure 1 illustrates a typical progression over time. The pattern of noise-induced hearing loss is particularly characterized by a "notch" usually centered at 4 kHz, although the notch may be centered closer to 3 kHz or 6 kHz. In later stages, the hearing loss may spread to the middle and even low frequencies. The disease is usually bilateral; however, there may be an asymmetry between the left and right ears. It is possible to see a unilateral noise-induced hearing loss when the exposure conditions favor one side of the head. In most cases, tinnitus will also be present.
Hearing-loss; Noise-induced-hearing-loss; Hearing-threshold; Hearing-disorders; Hearing-impairment; Noise-frequencies; Noise-exposure; Noise-levels; Chronic-exposure; Acute-exposure; Exposure-assessment; Occupational-exposure
Levy-BS; Wagner-GR; Rest-KM; Weeks-JL
Disease and Injury: Hearing Loss
Preventing occupational disease and injury, second edition