Produced noise level affecting the operator of agricultural tractor at different agrotechnical surfaces comparated to working hours

U radu su izneseni rezultati istraživanja mjerenja razine buke 2015., 2016. i 2017. godine i pri gibanju na tri različite agrotehničke podloge (trava, makadam i asfalt) u skladu s normama HRN ISO 5131 i HRN ISO 6396. Mjerenja su obavljena na površinama Poljoprivredne i veterinarske škole Osijek koristeći traktor firme Landini PowerFarm model DT100 i uređaj za mjerenje buke tvrtke Metrel model Multinorm MI 6201 EU s pripadajućom zvučnom sondom istog proizvođača. Istraživanja su obavljena s ciljem utvrđivanja povećanja razine buke koje utječe na trup rukovatelja u odnosu na starost traktora, tj. povećanja broja radnih sati traktora. Nakon istraživanja i iz rezultata vidljivo je kako izmjerena razina buke ne prelazi dozvoljenu razinu buke koja iznosi 80 dB. Međutim, postavljena hipoteza koja govori kako će stariji traktor s većim brojem radnih sati emitirati veću razinu buke od mlađeg traktora s manjim brojem radnih sati koja utječe na trup rukovatelja je potvrđena.This paper presents results of study regarding to the effect of level of noise in tractor, measured in 2015, 2016 and 2017, while operating on three different agrotehnical substrates (grass, macadam and asphalt) according to HRN ISO 5131 and HRN ISO 6396 standards. Measurements were performend on agricultural land of Agricultural and Veterinary School in Osijek using the Landini Powerfarm tractor, model DT100, and the Metrel model Multinorm MI 6201 EU noise measuring device with the sound probe of the same manufacturer. Studies were conducted to determine the level of noise which affects the body of tractor operator and compare their dependence on the tractor's age, as well as connection of noise with the increase in the working hours of tractor. After the survey, the results showed that the measured level of noise does not exceed the permitted level of noise of 80 dB. However , a hypothesis has been confirmed that the older tractor with a larger number of operating hours will emit a higher level of noise, affecting the body of the operator, compared to a smaller number of operating hours