Sources of pollutants from mine air pollution sources that cause atmospheric pollution in mines. The composition, traits and impact range of mine air pollution sources are closely related to deposit type, burial conditions, rock properties, mining metho.......

The protective mask is an industrial protective mask used for industrial protection of the eyes and face from harmful substances such as dust, chemical substances, hot gases, toxic gases, crumbs, and the like. It is mounted on the elastic head clamps with toothed knobs on the right and lef.......