One of the most relevant problems of the indus- trial cattle breeding is to make the optimal micro-climate in the cattle breeding places. The perspec-tive device for the ventilation air cleaning and disin-fection in the cattle breeding places is a special double-step irrigated precipitator. In the article there are results and the method of experimental investi-gations of the laboratory pattern of the double-step irrigated precipitator in laboratory conditions. The goal of the work was to get the experimental data about the optimal value of the voltage of corona-forming electrodes at the first and the second steps of the electric precipitator and to get the experi-mental data of the effectiveness of the ventilation air cleaning from the dust and microorganisms at all steps of the electric precipitator separately and combined. The double-step irrigated precipitator consists of 2 zonal irrigated precipitators differed from each other by the distance between separated electrodes and used liquids covering precipitating electrodes. At the 1-st step the liquid is water, at the second step - aqueous solution of copper sul-fate. Laboratory investigations were based on the Public autonomous professional educational institu-tion of the Tyumen region “Tyumen forestry engi-neering technical school”. The results were: the working voltage of ventilated air cleaning from dust and aerosols elements for the 1-st step was 32.9-98.31 % and for appropriate elements at the se-cond step was 20.29-50 %. The overall effective-ness of the double-step irrigated precipitator for the ventilation air cleaning from dust was 46.53- 99.15 %. The present method will become a base for the factory testing.