Influence of vibration exposure on tactile and thermal perception thresholds

Abstract

To establish if intermittent exposure to hand-transmitted vibration had the same effect as continuous exposure on the temporary response of finger tactile and thermal perception thresholds. Two laboratory experiments were conducted. In each, 10 healthy subjects, five males and five females, participated. The subjects' fingers were exposed to vibration under four conditions with a combination of different periods of exposure and rest periods. The vibration frequency was 125 Hz and the frequency-weighted acceleration was 5 m/s(2). A measure of the tactile or thermal perception was conducted before the different exposures to vibration. Immediately after the vibration exposure, the acute effect was measured continuously for the first 75 s. This was followed by regular measures for a maximum of 30 min. The results showed that combinations of vibration with different periods of exposure and rest periods significantly influenced vibrotactile perception, but not thermal perception. These findings suggest that intermittent exposure to hand-transmitted vibration might be more beneficial for the response of the finger vibrotactile sensation than continuous exposure. This finding is inconsistent with the evaluation methods in ISO 5349-1 for vibrotactile sensation, but accurate for thermal perception.