The purpose of this Master's thesis was to establish the physiological work load and the exposure of workers to noise and vibration as well as to determine the level of influence of the openness of the forest area with forest and skidding roads (skidding distance) on the work difficulty and the exposure of workers to physical agents in timber skidding operations executed with the Ecotrac 120V skidder. The measurements were conducted in the high Karst area in the southern part of Slovenia, i.e. in the mixed forest stands of fir and beech trees. The measurements lasted for six day in total, four of which evaluated the downhill skidding operations, while the last two days were reserved for the uphill skidding process. Along with the measurements of exposure to physical agents also the time study, measurements of the skidding productivity, and the determination of skidding conditions were conducted. Thecutting and skidding operations performance during the measured period were 338.2 m3, i.e. 56.4 m3/day in average. The average downhill and uphill skidding distance was 144 and 130 metres respectively. The results showed that the physiological work load in regard to average daily heart rate in a working day (HRwr = 44.5 bpm) exceeded the permanent permissible limit of 35 bpm, while in regard to the relative working heart rate (HRR = 34.5 %) it was below the permissible limit of 40%. The exposure to noise due to the lack of ear muffs application exceeded the action value and threshold values of the exposure according to the peak value of the sound pressure as well as considering the level of daily exposure (LCpeak = 140.7 dB(C), LAeq.kor = 89.7dB(A)). The exposure to the whole-body vibration calculated as the RMS values (RMS VTV = 0.89 m/s2) exceeded the action value, calculated as the total vibration dose (VDV VTV = 41.97 m/s1.75), as well as the permissible value of daily exposure. The measures decreasing the exposures to physical agents need to be directed to the regular use of ear muffs and the reduction of the daily productivity or should address the issue of job rotation.
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