The Zapolyarny mine widely uses high-performance mining systems with massive ore collapse when mining a thick gently dipping ore deposit. This is associated with the need to detonate large explosive charges during ore breaking and drawing and, consequently, with the contamination of the atmosphere of underground workings. To organize effective ventilation of stoping blocks, a properly designed ventilation scheme and systematic control of the causes of deterioration of atmospheric conditions at workplaces are important. ...