38 CFR §3.385

For the purposes of applying the laws administered by VA, impaired hearing will be considered to be a disability when the auditory threshold in any of the frequencies 500, 1000, 2000, 3000, 4000 Hertz is 40 decibels or greater; or when the auditory thresholds for at least three of the frequencies 500, 1000, 2000, 3000, or 4000 Hertz are 26 decibels or greater; or when speech recognition scores using the Maryland CNC Test are less than 94 percent.