Einzelstoßexposition auf das hand-arm-system – pilot zu physiologischen effekten

Occupational exposure to individual agents, e.g. when using certain tools (bolt guns, riveting hammers, etc.), has not yet been sufficiently studied in terms of its health effects on workers. There is evidence that machines and tools with low and high frequency shock-like exposure patterns can have adverse health effects on the vascular neuronal and muscular component of the hand arm system. The fact that the frequency of these activities is underestimated and that the recoils caused by these devices are underestimated in terms of their adverse health effects has therefore already been discussed by various authors in the past [1], [2]. This study evaluates if temporary changes in the vibrotactil perception threshold result from low frequency single shock vibration. In addition this study investigates the recovery of temporary threshold shifts after 15 min exposure with single shock stimulus. The right hand of 8 healthy subjects were exposed to single shock vibration under the same conditions, with 4 different frequencies (1Hz 4Hz, 20Hz and random signal) and a constant exposure time of 5 minutes. Before the single shock exposure and between each exposure the vibration perception threshold was measure on 5 different frequencies (8Hz, 32Hz, 125Hz, 250Hz, 500Hz). The vibration perception threshold increased consistently throughout the measurement spectrum after each exposure. Recovery to baseline levels was seen in the 8Hz, 32Hz and 125Hz frequencies, but was not reach in the 250Hz and 500Hz frequencies. Changes in the vibration perception threshold seem to have a cumulative effect over time, even when breaks are taken between exposures.