Temporary Threshold Shift Produced by Intermittent Exposure to Noise

The TTS at 4 kc was measured 2 and 17 min after successive 12‐min exposures to broad‐band noise at 106 db SPL separated by 18 min of silence. The results indicate that the TTS existing at the beginning of a particular exposure can be treated as additional time of exposure. Thus, if the residual TTS has a value that would be produced by R min of exposure, then the total TTS at the end of an M‐min exposure will be given by solving the equation for growth of TTS with exposure time set equal to M+R.