Edinburgh Napier University

  Existing risk assessment methodologies are based on fixed tool vibration magnitude emission data (such as tool declaration data or a point in time (typically annually) tool measurement to ISO5349) and tool usage time. The research evaluates the relationship between vibration dose assessment on subjects using wearable sensors with temporary threshold shift (TTS) in vibrotactile perception threshold and examine if this real use data would be beneficial for workplace risk assessment compared to the traditional approach of using a fixed vibration level. Human response to vibration, using TTS perception response, in male subjects (n = 12) exposed to hazardous vibration was undertaken. Simultaneous vibration measurements were undertaken on the subject and conventional measurements at the tool hand-grip interface in accordance with ISO 5349-2. Two modes of tool operation (drill and impact) and two postures (horizontal and vertically downwards) of tool use were considered. This choice of experiment was aimed at examining a range of vibration exposure from a controlled set of test conditions where conventionally a single vibration magnitude data point would be used in a risk assessment. The results demonstrate a more linear relationship between the hand transmitted vibration determined by the wearable sensor on the subjects and the human response to the vibration over the conventional measurement on the tool. It could be further hypothesised that control measures derived from in-use tool data would be more effective in reducing the underlying risk to operatives.