of Hearing Impairment and Disability”
Hearing impairment may be of various degrees (Ref.column 2 below). The degree of hearing impairment (in dBHL) as given in column 3 below is calculated by averaging the hearing thresholds at 500 Hz, 1 khz & 2 khz obtained from pure tone audiometry. Speech recognition score (Ref. Column 4 below) is obtained by administering Speech Audiometry. Hearing disability (Ref. Column 5 below) is calculated by the prescribed formula and is in percentage. The nature and quantum of benefits/facilities provided by the Government is based on the degree and percentage of disability.
|dB Level (HL)||
|I||Mild Hearing Impairment||26 to 40 dB in better ear||80 to 100% in better ear||Less|
|II (a)||Moderate Hearing Impairment||41 to 60 dB in better ear||50 to 80% in better ear||40%|
|II (b)||Severe Hearing Impairment||60 to 70 dB in better ear||40 to 50% in better ear||51%|
|III (a)||Profound Hearing Impairment||71 to 90 dB in better ear||Less than 40% in better ear||71%|
|III (b)||Total deafness||91 dB and above in better ear||Very poor discrimination||100%|