Hand-Arm Vibration

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Over the past few years, employers and manufacturers have become aware of the damaging effects of excessive vibration on the human body.

First to be recognised has been vibration transmitted to the hand by power tools such as breakers, grinders and chainsaws.

This leads to damage to the vascular system (Vibration White Finger or VWF), but also to joints, muscles (grip strength) and the nervous system (sense of touch).

To assess exposure (risk) we need to know both the magnitude of vibration and the typical daily duration.

Where reliable manufacturer's data is available, measurement may not be needed. Otherwise we measure 3 directions at each hand grip and combine to obtain a total value for each hand, following the guidance in ISO5349.

Estimating daily exposure requires information from workers and supervisors, interpreted with a degree of experience. Methods are available for combining exposure to several different levels of vibration within one day.