Hearing Safety Devices: System for Monitoring Exposure to Impulse Noise

This CDC-developed technology entails a system for monitoring and assessing the risk of auditory damage from exposure to impulse noise, such as noise created by construction machinery and firearms. Noise dosimeters have been used extensively over the past two decades to document personal exposure to noise and assure workplaces comply with permissible noise exposure levels. However, due to older methods of calculating "noise dose," current noise dosimeters often inaccurately determine the risk of an impulse event. Further, current state-of-the-art noise dosimeters have a sound pressure level (SPL) dynamic measurement range of about 80-146 dB, which is adequate for some impact noise environments, but cannot accurately measure impulse noise levels above 146 dB. When a dosimeter is used to measure a noise level greater than its dynamic range, the dosimeter “clips” the noise level at the upper end of its measurement range, resulting in errant assessments of noise exposure.

The system described by this technology can be used to measure exposure to impulse noise and replace older, "clipped-range" dosimeters. Additionally, this new technology will improve the collection of empirical data for establishing association of noise levels with hearing loss.