Purpose. To create the technology increasing the level of ecological safety of underground mining of iron ores by means of decreasing the number of harmful substances released into the atmosphere. Methodology. Laboratory and industrial research studies of the condition of the atmospheric air around mine arrangement were conducted by means of a physical-and-chemical method and biological testing. The standard method for calculation of their concentration in the atmosphere was used for determination of features of harmful substance dispersion. Findings. Regularities of ground concentration of total influence of harmful substances changing with taking into account a specific consumption of explosives and distance from an emission source are revealed. The dependence of conditional indicator of damageability of bioindicators changing with increase in distance from a source of emission and specific consumption of explosives is established. The method for calculation of ecological assessment of atmospheric air condition around an emission source is developed. Originality. Dependence of influence of ground concentration of harmful substances on damageability of bioindicators at the cellular and organismal levels is established, which allows estimating an ecological state of atmospheric air on industrial territories. Practical value. Regularities of inluence of ground concentration of total impact of harmful substances on a condition of indicator systems are determined that allows estimating the state of the environment and increasing reliability of local environmental monitoring around an iron-ore mine. The technology of drilling-and-blasting operations conducting in which emulsion explosives are used during mining of iron ores by means of the chamber mining methods, which allows decreasing the hazard index of harmful substances influence on the atmosphere, is developed and implemented. ; Мета. Створити технологію, що підвищує рівень екологічної безпеки підземного видобутку залізних руд шляхом зниження кількості ...