Some characteristics of human body surface vibration induced by low frequency noise

The body surface vibration induced by low frequency noise (noise-induced vibration) was measured at the forehead, the anterior chest and the anterior abdomen. At all the measuring locations, the increase steps in the vibration acceleration levels of the noise-induced vibrations was in good agreement with the increase steps, in the sound pressure levels of the noise stimuli. The vibration acceleration level measured at the forehead was found to increase suddenly at around 31.5-40 Hz, while the acceleration levels measured at the chest and abdomen increased with frequency at approximately constant rates in the 20- to 50-Hz range. Our results showed no clear evidence of the effect of posture or bilateral asymmetry in the noise-induced vibration. We found that the noise-induced vibrations measured at the chest and abdomen were correlated negatively with the body fat percentage.