Difference in the magnitude of power saw vibrations affecting the operator during forest felling

Abstract

Abstract This study deals with a question whether the magnitude of vibrations affecting the power saw operator during the tree felling is still the same or not. For this purpose, the tree felling was broken down into several partial operations (pruning of lower tree part; cutting of buttresses; felling; delimbing) at which the values of vibrations were recorded and mutually compared. The vibrations were measured during the felling of 121 trees with the activity being made by one feller with one type of power saw and one type of power saw chain, and the felled trees included both live and dead standing trees. The vibrations were measured on the front and rear handles of the power saw in compliance with standards EN ISO 22867, EN ISO 5349-1 and EN ISO 5349–2. As to the mutual comparison, research results demonstrated a difference in 69.23% of cases. A maximum increase of vibrations during the experiment (17.0 m s–2) was recorded on the rear handle during the partial activity of Delimbing live trees, the lowest increase of vibrations (0.320 m s–2) being localized in the same partial activity, only on the front handle.