We are excited to have you join us for an amazing educational line up, check out the agenda below for the 2025 Conference. Please note that this agenda is subject to change.
In-ear noise dosimetry offers benefits over traditional free-field or body-worn dosimetry because in-ear dosimeters measure actual noise exposure, including the as-worn attenuation provided by the subject’s hearing protection. Furthermore, impulse sounds may be accurately captured with microphones that have lower dynamic range and bandwidth requirements than those needed for freestream or body-worn dosimeters because the hearing protection moderates the peak levels and frequency characteristics of impulse sound waves. However, there are challenges to the use of in-ear dosimeters. The microphone must be integrated into an eartip that is comfortable and easy to use. The sound level measured by the ear-canal microphone should be related to the level at the eardrum and to the free-field, which is the level on which current permissible exposures are based. If the hearing protection device provides communications or a transparent hear-through mode, then any coupling between the microphone and speaker must be addressed. Consideration should also be given to artifacts induced by knocks or cable noise and to the effect of the wearer’s voice or other body noises. The practical benefits, challenges and constraints of in-ear dosimeters are presented through a discussion of the development and testing of a wireless in-ear dosimeter.
Learning Objectives: 1. Describe the differences between in-ear, body-worn, and free-field dosimeters. 2. Explain the relevance of noise levels measured at microphone, eardrum, and free-field reference points to permissible exposure limits. 3. Compare and contrast the characteristics of impulse sound waves measured inside hearing protection in the ear to those measured in the free field.
