A showcase of ÉTS researchers’ publications and other contributions

Development of a realistic artificial ear dedicated to earplugs attenuation measurements

Said Ezzaf, Luiz Melo, Poissenot-Arrigoni, Bastien, Saint-Gaudens, Hugo, Berry, Alain, Sgard, Franck and Doutres, Olivier. 2023. « Development of a realistic artificial ear dedicated to earplugs attenuation measurements ». [Conference paper summary]. Canadian Acoustics = Acoustique Canadienne, vol. 51, nº 3. p. 115.

The full text of this document is not available here.
Rechercher dans Google Scholar


“One size fits the most” disposable or reusable earplugs currently manufactured are not adapted to the diversity ofhuman ear canal morphologies. According to the standard ASA/ANSI S12.42, an objective method for designingearplugs is to use acoustical test fixtures (ATFs) comprising cylindrical ear canals of a signe size. Consequently,this ATF is unable to fully capture the inter-individual and the intra-individual variability when testing earplugattenuation and may therefore not be suitable for properly designing “One size fits the most” earplugs. Severalmore realistic artificial outer ears mainly intended for evaluating the occlusion effect have been developed in thepast by the ÉTS/IRSST research team, but have not been able to correctly reproduce the attenuation measured on areference human participant (from which the artificial outer ears were designed). These discrepancies can be partlyattributed to (i) the realism of the synthetic materials, (ii) defects due to the manufacturing process (presence ofair bubbles in the final part representing the soft tissue of the outer ear) and (iii) its self-insertion loss which maynot have been important enough and could not have been measured properly due to the small size of the outer ears.The objective of this work is to develop a realistic artificial ear dedicated to acoustical attenuation measurementsof earplugs and allowing for capturing the intra-variability due to fit and the measurement of its self-insertionloss. This ear is reverse-engineered from magnetic resonance imaging (MRI) images of the human head of a livingparticipant. The cartilage and bone parts of the artificial ear are manufactured using 3D printing whereas a moldingtechnique is used for soft tissues. Synthetic materials are chosen to have mechanical properties close to those ofbiological tissues. The ability of the artificial ear at measuring the sound attenuation of three families of earplugs(roll-down foam, push-to-fit, pre-molded earplugs) is evaluated by comparison with experimental data obtainedin a diffuse field carried out on the participant whose head was imaged. The next step will be to make a total ofthree artificial ears with three different ear canal morphologies (small, regular, large) to cover a larger part of thepopulation and capture the inter-variability.

Item Type: Peer reviewed article published in a journal
Additional Information: Thématique: Acoustics Week in Canada 2023. Montreal, QC, Canada. Oct. 03-06, 2023.
Doutres, Olivier
Affiliation: Génie mécanique
Date Deposited: 23 Nov 2023 16:51
Last Modified: 11 Dec 2023 14:58

Actions (login required)

View Item View Item