Evaluation of an earphone-support device for measuring earplug attenuation

Area of Science:

• Audiology
• Occupational Health
• Acoustics

Background:

• Accurate measurement of earplug attenuation is crucial for hearing protection.
• Standard sound field methods can be complex and time-consuming.
• Existing methods for measuring attenuation with audiometric headsets have limitations.

Purpose of the Study:

• To evaluate a new procedure for determining earplug attenuation using a modified audiometric headset.
• To compare the reliability and accuracy of this new method with established sound field procedures.
• To assess the performance of the new method across different test frequencies.

Main Methods:

• A novel device was used to support a conventional supraaural earphone cushion (MX-41/AR), preventing contact with the pinna or earplug during threshold measurements.
• Foam earplug attenuation was estimated on normal-hearing subjects using the earphone-support method.
• Results were compared to data from sound field (ANSI S12.6-1984) methods and simple earphone-on-pinna placement.
• Test-retest reliability was assessed for the earphone-support and earphone-only methods.

Main Results:

• The test-retest reliabilities of the earphone-support method and the earphone-only method were comparable to the sound field procedure.
• The closest correspondence between attenuation estimates from the support device and ANSI procedures occurred at 1 and 2 kHz.
• The new method demonstrated potential for reliable earplug attenuation measurement.

Conclusions:

• The evaluated earphone-support method provides reliable estimates of earplug attenuation.
• This method shows comparable reliability to standard sound field procedures.
• The technique is particularly accurate at lower frequencies (1 and 2 kHz) for estimating earplug attenuation.