Optoelectronic personal UV-meters were used to monitor the occupational facial solar erythemally effective exposure of 12 Austrian full-time farmers with high temporal resolution. To ensure high quality measurements several quality assurance procedures were applied, like calibration with respect to solar elevation and total ozone column. From April to October the test persons carried the UV-meters on the forehead during working hours. A digital diary (activity, location, weather, photoprotective measures) was completed on an hourly basis. Our field test produced 1427 complete daily records (measurement and diary). The total exposures showed high variability (77-757 standard erythema dose [SED]) which correlates with the number of working days and even stronger with the little numbers of days with high exposure (>10 SED). Risk factors for high exposures were: mixed-culture farms with aggravated working conditions, low degree of automation of working processes, inadequate operating logistics (summarized as manual work outdoor), driving machines without cabins, and female gender. UV exposure of female farmers was approximately twice as high as that of men: Women received 15% of ambient radiation while men got 8%. Avoiding daily exposure >10 SED could reduce exposure down to 40% and the risk in developing skin cancer by a factor of 40.