Noise Induced Hearing Loss

Noise-induced hearing loss (NIHL) is a hearing impairment resulting from exposure to loud sound. People may have a loss of perception of a narrow range of frequencies, impaired cognitive perception of sound, or other impairment, including sensitivity to sound or ringing in the ears.

Hearing may deteriorate gradually from chronic and repeated noise exposure, such as loud music or background noise, or suddenly, from a short high intensity noise such as a gunshot or air horn. In both types, loud sound over stimulates delicate hearing cells, leading to the permanent injury or death of the cells.

Contents

• Definitions and terminology
• Identify noise hazards
• Control measures
• Case Study.
• Assessment.