COMFORT FROM USING FOAM EARPLUGS – PROJECT FOR A STUDY

Comfort is an important characteristic of hearing protectors, as important as the sound attenuation. A bibliographical study was performed by Behar and Segu (submitted) examining research on comfort from hearing protectors published during the last 25 years. The study was a background document for developing a procedure for ranking comfort of hearing protectors on the basis of physical characteristics. The paper’s main recommendation was work on only one type of protector. (Prof. S. Gerges, Universidade Federal de Santa Catarina, Brazil is studying comfort from ear muffs exclusively). The current project will focus on comfort from foam earplugs exclusively. Twenty participants will evaluate twelve types of foam earplugs. Each participant will be asked to assess the comfort using a visual analog scale. In addition, wax molds will be obtained from the ears of all participants. These molds will be digitized to obtain the shape and size of the ear canal. The physical characteristics of the earplugs will also be measured (density, stiffness, diameter, etc...) Finally, a correlation will be sought between the physical characteristics of the plugs and the comfort experienced by the participants. A multiple regression approach will be used to assess the influence of physical measures including stiffness, size, density, shape, and material on comfort ratings obtained across individuals with ear canals of varying diameter. The models will be realized as formulae specifying proportion of variance accounted for by each factor, the weight of the factor and the directionality. This formula could then be used to classify any foam plug that may be developed after completion of this study.