Attenuation characteristics of hearing aid earmolds

The purpose of this study was to determine the attenuation characteristics of several hearing aid earmolds. Six earmolds and an E-A-R earplug modified to act as an earmold were evaluated according to the standard procedure. The six earmolds consisted of two types (shell and skeleton) having different materials (Lucite and vinylflex) and different styles (normal and tragus lock). The traditional earmolds provided approximately 17 dB less attenuation as compared with the E-A-R earmolds. The attenuation provided by the traditional earmolds was not influenced by the type, material, or style. The traditional earmolds had a noise reduction rating of less than 3.3 dB, whereas the noise reduction rating for the E-A-R earmolds was greater than 18.2 dB. Traditional earmolds should not be considered as a substitute for a hearing protection device. However, E-A-R earmolds could be used as a substitute for a hearing protection device provided the level of the noise minus the noise reduction rating would be acceptable.