Dissertations, Theses, and Capstone Projects

Date of Degree

6-2026

Document Type

Doctoral Capstone Project

Degree Name

Doctor of Audiology

Program

Anthropology

Advisor

Don Vogel

Subject Categories

Speech Pathology and Audiology

Keywords

Earplug, Hearing protection device, attenuation, KEMAR, Noise reduction

Abstract

Recreational and social environments frequently expose individuals to high intensity noise environments; however, the use of hearing protection devices (HPDs) remains limited. This study evaluated whether non-custom, over-the-counter musicians’ earplugs provide attenuation consistent with manufacturers’ claims and whether cost is associated with performance. Six commercially available earplug models were tested using both human participants and a KEMAR manikin system. Attenuation was measured across frequencies from 250–8000 Hz (octave and inter-octave frequencies) and were tested using different ear tip sizes. Results indicated that several earplugs achieved attenuation levels comparable to or exceeding their advertised noise reduction ratings (NRR), though consistency varied across models. Earplugs such as Loop Experience and Etymotic ER20XS demonstrated consistent attenuation performance, while others showed greater variability. Tip size significantly influenced performance, with larger tips providing greater attenuation, highlighting the importance of proper fit. No clear relationship was observed between cost and attenuation performance. Overall, findings suggest that while non-custom earplugs can perform effectively, individual fit and comfort play a critical role in real-world performance.

Download

Share

COinS