The purpose and the aim of the thesis was done to determine how different preparations of a chain of the chainsaw, the type of the chain and the tree species affect on the worker who is exposed to vibration of his hands and palms. To determine the exposure to vibration during crosscutting prismatic wood of fir and beech has been used, which was previously shaped by circular band saw to the dimensions of 32 cm x 32 cm, errors of wood were eliminated during the experiment. For the experiment the chainsaw Husqvarna 372 XP was used for crosscutting, on which the rack Stihl of 45 cm length, with 1.6 mm groove and the chains of Stihl and Oregon was placed, which were previously sharpened under three different angles of sharpened blade and three different depths of deep teeth. Measurements were carried out with - Pulse LAN Xi manufactured by Brüel & Kjær, which was connected through the cable to the accelerometer which was installed at the forefront handle of the chainsaw. The results of the analysis showed that the intensity of vibration, not taking into account the height of the depth of teeth is the lowest at the corners of the sharpened blade as recommended by the chain manufacturer. Taking into account the height of deep teeth the intensity of shaking is weaker with lower depth of teeth and smaller corners of the focus of blade as recommended by the chain manufacturer. At crosscutting with Oregon chains the intensity of vibration is smaller than the Stihl chains and lower at processing of fir and beech. The research findings are useful for reducing the burden of the hands and palms of a professional forest worker and the occasional chainsaw user.
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