A new approach to assess low frequency noise in the working environment.

To assess high-level low frequency noise in the working environment, adverse extra-aural effects caused by the noise should be taken into account. The human body vibration induced by low frequency noise, 'noise-induced vibration', was measured on the body surface and the equal-acceleration level contours of the vibration were tentatively estimated. With these contours, we can predict the magnitude of noise-induced vibration at every measuring position on the body surface. This is helpful in relating the total dosage of low frequency noise with the physical symptoms caused by the noise. But some important points in the contours remain to be investigated and improved. When these points are dealt with, the equal-acceleration level contours will be useful for assessing high-level low frequency noise in the working environment from the standpoint of predicting the adverse extra-aural effects.