Using Implementation Science to Improve the Adoption of Hearing Protector Fit Testing in the Department of Defense

The Department of Defense (DoD) Hearing Conservation Program was established to prevent hearing loss from occupational and operational exposure and injury, as outlined in Department of Defense Instruction (DoDI) 6055.12. Updated November 22, 2023, DoDI 6055.12 now requires quantitative hearing protector fit testing (HPFT) to objectively measure the noise reduction hearing protection provided to an individual's ear. Although HPFT is recognized as an evidence-based best practice, it has not been widely adopted. An Implementation Science approach was applied to better understand the challenges associated with putting this new requirement into practice in the DoD. A mixed methods approach was used, including 2 rounds of semi-structured interviews and a course evaluation survey. These instruments were developed to assess determinants (barriers and facilitators) and influence the implementation of HPFT training in the DoD. Responses informed training materials already in development. Barriers identified through semi-structured interviews and course evaluation included: (1) difficulty determining target personal attenuation rating, (2) difficulty connecting HPFT systems to the network, (3) not having direct access to workers' noise exposure data, (4) space, (5) time, (6) equipment procurement, (7) stakeholder buy-in, and (8) inability to transfer HPFT data into the electronic medical record. Facilitators included evidence strength, ease of use, leadership buy-in, and appreciation from patients. This work prompted the development and refinement of HPFT training materials, including the creation of new resources (i.e., infographic and quick reference guide), simplification of terminology, and transfer of web-based training to a more user-friendly platform. Results suggested that web-based training, in conjunction with a practicum and user guide, is an effective model for teaching HPFT administration. These findings will influence the development of additional training materials and knowledge products to assist providers and others as they work to implement the new DoDI 6055.12 HPFT requirements.