The relationship between personal attenuation rating and the risk of significant threshold shifts in military personnel

Hearing protector fit testing (HPFT) ensures individuals achieve adequate Personal Attenuation Ratings (PAR) from hearing protection in noisy environments. However, the relationship between the measured PAR and the risk of future hearing loss remains poorly understood. This study examined PAR and audiometric data from 1829 military personnel during required annual hearing conservation appointments. PAR was compared to significant threshold shift (STS) rates experienced in the 12-month period prior to the hearing test. HPFT was performed without immediate training to assess baseline fitting proficiency at the time of the scheduled appointment. The results indicate that individuals with the lowest PAR (0 dBA) had significantly higher STS rates than the remaining sample, and that individuals with the highest PAR (35 dBA) demonstrated markedly lower STS rates. This evidence supports efficient and effective HPFT implementation in hearing conservation clinics by linking protection ability directly to hearing loss prevention outcomes.