Mining Publication: Emerging Technologies Control Respirable Dust Exposures for Continuous Mining and Roof Bolting Personnel

This paper presents the findings from a number of NIOSH studies evaluating the impacts of emerging technologies that may reduce dust exposures for continuous mining and roof bolting personnel. These technologies include use of a wet-head cutting drum on a continuous mining machine that places water sprays on the cutting drum instead of on a manifold outby the drum. Evaluations at two separate operations showed that the use of the wet-head sprays reduced dust levels at the miner operator in the return air, although these reductions were quite variable. NIOSH also assessed the effectiveness of a canopy air curtain for protecting roof bolting personnel. The data showed that dust levels were lower beneath the air curtain than outside the air curtain. This study also suggested several future modifications to the air curtain to increase its effectiveness. Finally, NIOSH evaluated mist drilling technology for its effectiveness in controlling respirable dust exposures of bolting personnel. A recent study showed that higher dust levels existed around a machine using the mist system compared to a machine using a conventional vacuum system for dust control. Unfortunately, the true impact of mist drilling was confounded by this machine operating downwind of the continuous miner for much of the study.