Proposal for an Ergonomic Conformity Index for Evaluation of Harvesters and Forwarders

Abstract

-Context: In mechanized forestry work, the ergonomic conditions of the workplace affects operator's health, performance and productivity. Originality: A comparison of different forest machines becomes complex in case where it is required analysis of several ergonomic factors simultaneously. There are several methods of ergonomic analysis however, a more complete methodology that considers several ergonomic factors and produces an index that represent the ergonomic condition of the machine is needed. Objective: Propose a methodology to determining an Ergonomic Conformity Index to evaluate Harvesters and Forwarders of different brands. Methodology: The ECI was determined initially basing in four relevant ergonomic factors: noise, vibration, thermal environment and air quality. These factors were evaluated utilizing four Harvesters and two Forwarders in eucalyptus timber harvesting operations. For each factor, a score was given according to its compliance with the established parameters. The ECI was obtained from an average of the scores given to each factor. The index ranges from zero to one, so that lower values indicate worse ergonomic conditions. Results: All the analyzed machines had continuous noise between 75.0 and 82.6 dB (A) and whole-body vibration between 0.27 and 0.70 m s -2 . HV1 and HV2 presented thermal environment in accordance with the established criteria, other machines showed deficiencies in this regard. All the machines presented non-conformities in the air quality, except HV2. The ECI of Harvesters HV1, HV2, HV3 and HV4, were 0.83; 0.88; 0.71; 0.63. The ECI of Forwarders FW1 and FW2 were 0.58 and 0.79. Conclusion: The determination of the ECI allowed an evaluation and comparison between analyzed forest machines. The machine with the higher ECI had only one non-conformity, and it was related to noise inside the cab. The machine that got the lower ECI presented non-conformities for all the factors. Keywords: Forest harvesting; Forest mechanization; Occupational hygiene. ÍNDICE DE CONFORMIDADE ERGONÔMICA PARA MÁQUINAS FLORESTAIS

Influence of Pump Pressure and Engine Speed on Ergonomic Parameters of Forwarder Operators

“…In research carried out with diff erent types forwarders, an average Aren value of 0.70 m s -2 was observed. These values were lower than that observed in the current research, whtich resuled from diff erences in operating conditions and machines used in the research (Marzano et al, 2017). The forwarder vibration values are infl uenced by the diff erent models of the machines and operators (Rehn et al, 2005).…”

Influence of the Harvester Operation Mode on Ergonomic Parameters of Operators

“…Similar results were found by Santos et al (2020). Marzano et al, (2017) evaluated the acceleration values resulting from normalized exposure of different harvester models, and determined a value of 0.37 m s -2 . On the other hand, Sherwin et al, (2004) determined the acceleration values between 0.277 and 0.527 m s -2 , for a harvester operating with different tire inflation pressures.…”

Análise da exposição à vibração de corpo inteiro em harvesters de esteiras e pneus na operação de desbaste

“…Marzano et al [11], realizaram análise comparativa entre as máquinas florestais harvester e Forwarder e, dentre os fatores de avaliação, identificaram níveis de vibração entre 0,27 e 0,70m/s² na colheita de madeira de eucalipto. Os resultados identificados pelos autores estão de acordo com níveis de aren encontrados no presente estudo, demonstrando que as operações de colheita florestal com o harvester apresentam níveis de vibração próximos do nível de ação (0,5m/s²).…”