Heat stress appears as a strong candidate for physical wear and tear, leading to lower yields and high risks of accidents due to lack of attention. In this context, this work aims to study the possible influence of the internal temperature of metal roof tractor, skin temperature of face operator, relating it to possible physiological responses connected with environmental variables such as relative humidity air and wind speed. An insulating composite panel based on residual materials (cement

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... ) was prepared and placed under the tractor roof for thermal isolation purpose. The tractor used in the experiments is manufactured in 1997, with engine power of 173 hp at 2200 rpm; it works for 8200 h and has original factory roof. The experiment was carried out in the open field for five days, following the same start time (11 h 40 min) and ending time (13 h 40 min); it corresponds with the maximum sun intensity, where in the first hour there was panel and after 12 h 40 min, there was no panel. After analyzing the data, there was a reduction in the average temperature inside the cabin with the presence of the insulating panel. The physical workload, based on heart rate, remained in "light" range, even with no physical requirements for the operator. Regarding the average temperature facial skin, it showed an increase of 1.1°C after the panel removal. According to the classification of temperature level and humidity, despite a steady increase in value during the 2 h of the experiment, the index remained in the position of little discomfort. Based on the data, it is clear that simple measures can be taken to improve the thermal environment in tractors with roof control platform, in addition to stimulating the study for improving cooling in tractor cabin.