Studies of farmers' annual exposure to whole body vibration on selected family farms of mixed production profile.

The objective of the study was to recognize and evaluate the annual exposure of private farmers to whole body mechanical vibration on selected family farms of mixed production profile (plant-animal). The scope of study covered the carrying out of time schedules of agricultural activities, and measurements of the frequency weighted vibration acceleration (m/s(2)), expressed as effective values (r.m.s.) for each of three spatial directions on the seat surface within the period of the whole year. The basic vibration parameter was vibration dose (d). The following values were determined: total monthly vibration dose, mean equivalent daily vibration dose, and mean equivalent daily vibration acceleration. The highest values of the total monthly vibration dose (d) were observed in April and August (55.3-56.7 m(2)/s(4).h). The mean equivalent of daily vibration acceleration showed the highest values in four months of the year: April, August, September and October (0.49-0.60 m/s(2)); the average value of this parameter for the whole year reached the level of 0.44 m/s(2) - below the standard. Due to the occurrence in agricultural vehicles of mechanical shocks (mean values of maximum vibration acceleration: 0.82-1.00 m/s(2); exceeding the standard), and exceeding of the daily exposure action value, proper steps should be undertaken with respect to the protection of private farmers against risk resulting from exposure to mechanical vibration while performing work activities.