The paper is devoted to the problems of designing of ventilation systems meaning the choice of equipment for the main ventilation unit for mines taking into account possibilities of current market of equipment. Prospects of using these units based on centrifugal and axial ventilators are estimated as well as the list of factors having substantial effect on determination of actual parameters of ventilation net and required characteristics of designing ventilation unit; features of comparison of aerodynamical characteristics of imported axial ventilators; basic construction features of axial ventilators.