Navy hearing conservation program: hearing threshold comparisons to Navy SEALS and divers

The study examined hearing threshold for Navy special operations personnel (SEALS (Sea-Air-Land): N = 212; divers: N = 165). Hearing threshold values were obtained and age adjusted using Mantel Haenzel Weighted odds ratio (MHOR) to compare with information in the Navy Hearing Conservation Database. For any threshold above 20 dB in the 500 through 3000 Hz range, the SEALS were significantly less at risk (MHOR = 0.54, p = 0.022) in the right ear, while the divers were significantly less at risk in the left ear (MHOR = 0.61, p = 0.047). For hearing thresholds at 4000 Hz above 40 dB, SEALS were significantly more at risk in both left ear (MHOR = 2.03, p = 0.0043) and right ear (MHOR = 2.58, p = 0.000089), while divers were not different. Risk assessment based on these findings must consider the multiple exposure hazards and critical mission profiles for the Navy special operations personnel. Requirements for mission accomplishment in hazardous environments may deem these risks acceptable.