Níveis de ruído emitidos por trator agrícola durante operação de pulverização em diferentes condições de trabalho

Abstract

The evolution of agricultural mechanization has improved operational and productive performance, reduced human physical effort, and increased productivity per area. However, the worker remains exposed to several occupational risks when operating an agricultural machine, whether physical, chemical, or biological, increasing the incidence of occupational diseases. The noise generated by agricultural operations is considered one of the main ergonomic factors harmful to the machinery operator and people close to the noise range, affecting not only the hearing, but the well-being and performance in carrying out the work, increasing the possibility of accidents. Thus, this work aims to quantify the noise levels emitted by an agricultural tractor, considering different distance radii and engine speeds, evaluating the influence of air-assisted sprayer activation on noise levels. The test was carried out in an experimental area of the Laboratório de Mecanização Agrícola do Pampa – Campus Alegrete, in the municipality of Alegrete/RS. As a source of noise, an agricultural tractor, and a sprayer with air assistance on the spray booms were used. Noise levels were captured using a portable noise dosimeter (digital decibel meter). The treatments consisted of air assistance from the sprayer (off, medium, and maximum capacity), engine speed (1400, 1600, 1800 and 2000 rpm) and distance radius in relation to the tractor (operating station, 1.0 m, and 7.5 m). Noise levels showed dependence on the distance radius, engine speed and activation of the air assistance on the spray booms. The influence of emitted noise decreases with distance from the noise source. The air assistance on the spray booms generates an increase in emitted noise levels, which increase with the increase in fan speed. Considering an eight-hour working day, more than 50% of the measured noise levels are within the daily limit allowed by Regulatory Standard No. 15 (NR 15), without the use of hearing protection devices. However, for the operator and workers close to the machinery, it is necessary to use Personal Protective Equipment (PPE).