Estudos ergonômicos e rendimentos da exploração florestal na caatinga.

Abstract

Global warming has drastically affected the climate, causing serious changes. This aggravation is due to various anthropogenic factors and, in particular, the gases released in semi-mechanized forestry activities. Furthermore, the use of chainsaws has advantages and disadvantages for employees, employers and the environment. In view of the above, the aim of this study was to analyze the emission of carbon dioxide gases and to verify the emission of vibration and noise in semi-mechanized harvesting, as well as to assess the productivity of manual forest harvesting operations in a Caatinga area. The work was carried out in a forest management area located in the municipality of Mauriti, in the southern region of Ceará. The following data was analyzed in the study area: gas emissions, using a gas analyzer; vibration emissions in the hand-arm system, using an accelerometer; noise emissions, using a dosimeter; and productivity of semimechanized harvesting operations, using a stopwatch. After collecting and analyzing the data, an average carbon dioxide emission of 115.75 ppm was obtained from the chainsaw exhaust. The operator's exposure to vibration was found to be 4.06 m.s-2, which is within the range between the action level and the exposure level for an 8-hour working day according to NHO 10, but it is necessary to use PPE to mitigate the risks to the operator's health. With regard to noise, semi-mechanized logging meets the minimum sample limit at the 5% significance level for the average level of operator exposure. The volumetric estimate for the study area shows an average production of 48.14 m³.ha-1. After observing the data obtained, it is conclusive to say that the average concentration of carbon dioxide found in this research does not entail risks to the operator's health, that the operation of the chainsaw emits noise levels above the permitted values. As for vibration, the use of the machine exposes workers to uncertain levels of health risk. Finally, the productivity of logging activities is directly linked to the volume of wood, the dendrometric characteristics of the trees and the process of anthropization of the forests.