THE EFFECT OF IMPULSE NOISE ON HEARING OF GUINEA PIGS IN THE CONTROL ROOM OF MISSILE LAUNCHING VEHICLE / 解放军医学杂志

The present paper deals with the effect of impulse noise, which is produced by launching of miniature tactical missiles, on hearing of guinea pigs situated in the control room of the missile launching vehicle. 20 normal hearing guinea pigs are placed in the control room in which impulse noise level is 160-170dB (sound pressure level) and duration is longer than Is. 48h after sound exposure, the mean threshold shift is 2 dB, and threshold shift of 2/40 ears is greater than 10dB. Histological observation reveals that cochlear hair cells are undamaged in 15 ears. Howeves, staining on bloc shows hydrops of cochlear partition in 5 ears.