[Dust and gas factors in extraction of polymetallic ore in Arctic conditions and their hygienic assessment].

Studies of drilling and blasting method of copper and nickel ores extraction at underground Transpolar mines proved that the highest concentrations of dust appeared during dry drilling of vertical blast holes, work of scraper windlass, fragmentation of out-size blocks, preparation of concrete mixture. Presence of aggressive metals, especially nickel, in the ore dust is a main base for planned thorough investigations of fibrogenic, toxic and carcinogenic effects of copper and nickel ore dust, for more precise assessment of its MAC in the air of workplace. Two-step purification of exhaust gases appearing due to mining diesel machines is not quite efficient, as the concentrations of nitrogen oxides (assessed through nitrogen dioxide) continually exceeded the MAC.