The purpose of graduation thesis was to answer the question whether the cutting and processing of dry spruce trees presents higher exposure of lumberman’s arms to vibrations when compared to fresh spruce trees. The survey was conducted in the area of hill Ljubljanski vrh in GGE Bistra-Borovnica, GGO Ljubljana. In the survey 10 spruce trees was covered, 5 of those damaged by ice storm and bark beetles, and 5 fresh trees. All 10 trees were processed by the same lumberman in the same day. Lumberman exposure was determined on the rear handle of chainsaw Husqvarna 562 XP. The results have shown, that the vibrations loads were smaller during processing of fresh spruce trees (4,36 m/s2) than during working with dry trees (4,87 m/s2). Therefore, the differences are statistically significant, but the difference cannot be clearly visible when comparing each individual work operation. In addition to applying technical measures, in order to reduce vibration load on forestry workers, the results of the research should be considered particularly when organising work on salvage logging worksites containing a high concentration of dry wood.
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