Diagnosis and quantification of military noise-induced hearing loss.

The diagnosis and quantification of noise-induced hearing loss (NIHL) in a medico-legal context are usually based on the pattern of hearing loss that is typically associated with long-term exposure to steady broadband noises, such as occur in noisy factories. Evidence is reviewed showing that this pattern is not typical for hearing loss produced by intense impulsive sounds of the type that military personnel are exposed to. The audiometric characteristics of noise-exposed military personnel are reviewed. A set of audiograms from a sample of 58 hearing-impaired noise-exposed military veterans was analyzed and used to develop methods for the diagnosis and quantification of military NIHL. Three requirements are specified for diagnosing military NIHL. Quantification of any loss is done by comparison with audiometric thresholds for non-noise exposed individuals, as specified in ISO7029 [International Organization for Standardization, 2017].