Effects of industrial noise on the human's heart rate variability

The authors studied the human's heart rate variability(HRV) which was influenced by the noise under different frequencies,different noise levels and varied noise exposed conditions.The experimental results indicated that the effects of the noise frequencies and exposed conditions on HRV during R-R interval period were significant.The noise exposing made the R-R interval period decreased and this kind of decreasing trend will last for a period of time after the noise was stopped.It is concluded that the noise near 500 Hz has less sthenic effect on the sympathetic nerve than those of the other noise frequencies.