The most recent advances in sensor technologies have given rise to a proliferation of applications using frequently gathered data to continuously improve operational performance. The authors seek to illustrate whether such an approach is valid in the control of exposure to harmful vibrations from power tools. The authors investigate the range of exposure possible when closely monitoring a single task and analyse a large set of monitoring data from a wearable devise for possible under-assessment of risk. The investigators conclude that over reliance on generic risk assessments may place certain individual tool users at greater risk. Modern monitoring devices can help identify at risk individuals and assess the effectiveness of control measures.