In noise induced hearing loss , audiogram shows a Boiler's notch at ?: (A) 1000 Hz, (B) 2000 Hz, (C) 3000 Hz, (D) 4000 Hz
Answer is D. Noise induced hearing loss Boiler notch at 4000 HZ Max seen at 3000 - 6000 HZ Sterocilia of outer hair cells are 1st to be affected . Carha's notch - dip is present at 2000 HZ .(seen in otosclerosis)