Noise levels during the mechanised operations in protected crops

Given the lack of information in scientific literature, the present paper reports the primary results of a research on the daily noise exposure of the workers assigned to plant protection and soil tillage. The research concerns an air-carrier sprayer with mechanical atomisation and axial fan, a knapsack sprayer, a rotating plough and a hoeing-machine. In any case, the sound pressure levels are high enough to require the use of personal protection devices for hearing. In detail, the tests with the air-carrier sprayer, carried out in a vineyard in greenhouse, showed values of sound pressure level near 90 dB(A), greater by almost 2 dB(A) than those recorded in an open field vineyard. This result leads us to believe in a positive influence of the coverage on the noise. The knapsack sprayer showed values greater than 100 dB(A), due to the proximity between the microphone, and therefore the ear of the operator, and the engine of the machine. Finally, the soil tillage caused sound pressure levels of some 94.5 dB(A) during the hoeing and of some 87.8 dB(A) during the ploughing.