Ground level air was drawn through polystyrene air filters by means of high volume air samplers. The filters were changed weekly during a 5-month period. The sampling devices were in operation at various sites located between 2 and 18 km from the Swedish nuclear power station at Ringhals, 52 km south of Gothenburg. Besides global radioactive fallout the filters also contained the activation products 60Co, 65Zn and 58Co attributed to airborne releases from the power station. For shorter distances (< 6 km) the relative concentration of 60Co as a function of distance in ground level air is in quite good agreement with values predicted by a Gaussian dispersion model. For distances greater than 6 km, however, the experimental data are in better agreement with the decreasing power function, earlier suggested in connection with our studies of the variation of 60Co concentration in sewage sludge, collected at various distances from a nuclear power plant.