Ergonomic factors and production target evaluation in eucalyptus timber harvesting operations in mountainous terrains Amaury Paulo de Souza 1 , Luciano José Minette, André Luis Petean Sanches, Emília Pio da Silva, D.S, Forest Science; Valéria Antônia Justino Rodrigues, Luciana Aparecida de Oliveira Ergonomic Laboratory – Forest Engineering Department, Federal University of Viçosa, 36570-000 - Viçosa, Mi- nas Gerais, Brazil Abstract. There are several forest operations involved in Eucalyptus timber harvesting. This study was carried out during brush-cutting; tree felling, bucking, delimbing, piling and manual extraction operations, with the following objectives: a) ana- lyzing, ergonomically, two systems of brush-cutting: one manual and the other semi-mechanized, using two different ma- chines; b) ergonomically evaluating three different brands of pruner machines used in delimbing felled trees. c) determining the feasible target of productivity as a function of ergonomic factors relevant to establish the time of resting pauses for workers in manual and semi-mechanized timber harvesting systems in mountainous terrain. Brush-cutting, either manual or semi- mechanized, is an activity carried out prior to timber harvesting. It is usually a hard work, with low productivity when com- pared with mechanized systems. Pruner machines have been used by forest companies, due to the great possibilities to improve productivity, quality and the health of workers. Ergonomics is a discipline that promotes the adequacy of work to the physical and mental characteristics of human beings, seeking to design production systems and products considering relevant aspects, including social, organizational and environmental factors. Companies should consider the ergonomic factor in the determina- tion of daily worker production targets. Keywords: Productivity, forest workers; work performance 1 Corresponding authors. Emails: maury@ufv.br, minette@ufv.br, florestandre@yahoo.com.br, valeriaufv2001@yahoo.com.br, luolijsc@yahoo.com.br. 1. Introduction 1.1 Brush cutting problems Several machines, implements and tools can be used in timber harvesting to help workers in their job. Sickle is a tool used in manual brush-cutting opera- tions in mountainous terrains. Due to relative lower price of motorized brush-cutters and tree pruners, there has been greater use of these machines to in- crease productivity and well-being of workers in op- erations for cleaning Eucalyptus stands. Some brush-cutters and tree pruners available in the market have design deficiencies, including exces- sive vibration and noise, which can damage the health and safety of workers [6]. 1.2. Tree delibing problems Tree pruner machines have been used by forest companies to delimb felled trees, instead of the ma- nual method, with the use of small axes. The tree pruner is a machine similar to the chain- saw with respect to its engine. However, its cutting component is different, which is fixed on the tip of a telescopic rod with length ranging from 2 to 5 m. Some pruners available on the market have design deficiencies, including excessive vibration and noise, which can damage the health and safety of workers. 1.3.Ergonomic problems 4957 Work 41 (2012) 4957-4962 DOI 10.3233/WOR-2012-0038-4957 IOS Press 1051-9815/12/$27.50 © 2012 – IOS Press and the authors. All rights reserved