In the light of studies of dustiness in agriculture conducted in Poland and abroad, which deal exclusively with dust risk while performing selected occupations, the results presented in this article are a subsequent attempt to recognize annual exposure to dust at workplaces in agriculture. This recognition concerns the workplace of private farmers--typical of Polish agriculture--on family farms of various profiles of production. The study covered 10 selected farms: four animal breeding farms, four specialised cultivation farms, and two traditional mixed-production farms comprising animal breeding and plant cultivation. The results of the study showed an unequal distribution of the working time load and exposure to dust among the farmers examined during the whole year. The monthly working time limit ranged from 53.6-208.8% of the legal working time. The values of the mean weighted monthly concentrations of total dust ranged within 1.2-33.9 mg x m(-3), and those of respirable dust - 0.3-4.0 mg x m(-3), the highest values being observed in August and September. Mean weighted monthly concentrations describing an average level of farmers' exposure to total dust (7.7-21.9 mg x m(-3)), together with the confidence intervals, remain above the occupational exposure limit (4.0 mg x m(-3)), which is equivalent to hazardous conditions. In the case of respirable dust the results obtained show allowable conditions. Despite this, the dusty working conditions of the farmers in the study should be regarded as hazardous, due to the high level of exposure to total dust observed and potentially high contents of pathogenic components. The highest level of exposure was noted on farms engaged in potato production and marketing, followed by traditional farms carrying out mixed production, while the lowest level of exposure was observed on farms engaged in dairy cattle breeding.