Exposure to vibration when using hand tools is unavoidable. In Europe, the standard for testing hand tools, EN 62481, specifies the requirements for vibration testing on handheld tools. They are measured in an accredited laboratory and the values of these vibrations are written in the instructions for safe use. In industry, construction and forestry, workers using power tools are most exposed to the long-term effects of vibration in the hands, fingers and arms. Exposure to this type of vibration can have a very detrimental effect on the quality of life of the affected workers, both during work and in their free time after work is finished. The vibrations damage blood vessels in the fingers, weaken muscles and damage the nervous system. The consequences of such injuries are often permanent and incurable. It is therefore very important that manufacturers of hand tools reduce vibration as far as they can. Employers and users of hand tools should follow recommendations that reduce the impact of vibration.
The aim of this thesis is to investigate the effects of hand tool vibration on users. I have researched the effects of vibration on humans, analysed the symptoms of affected workers and described how symptoms are measured in healthcare. I described methods of vibration reduction in tool design and analysed the process of vibration measurement using a practical example of a handheld tool. I described the different types of sensors that can be used to measure vibration and where they are used. I also considered the effects of varying the measurement parameters, which have a major influence on the final result. I have presented the findings of the testing in tables and graphs. I have calculated the uncertainty of the final results.
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