Acta Scientiarum Polonorum
Silvarum Colendarum Ratio et Industria Lignaria

The aim of the performed experiments was to assess energy expenditure and static loads of the operator of a chain sawing machine harvesting timber in a pine stand intermediate cutting. The investigations included two technological variants. In variant I, all technological operations were carried out by one worker – operator of the chain saw, while in treatment II the operations were carried out by a team of three persons – two operators of chain sawing machines and a helper. The energy expenditure was determined on the basis of measurements of the ventilation of lungs, whereas the static load – using the OWAS method. The determined net unit energy expenditures of the chain saw operators in the experimental variants exceeded 20 kJ•min-1 and differed statistically significantly between one another. With regard to static loads, a greater proportion of positions negatively affecting the muscle-skeletal system of the operator were found in variant II.