The above mentioned tests showed that the efficiency of
airborne dust reduction is higher in the case of using the airand-
water spraying system (42% for total suspended particulate
matter, and 93% for respirable dust) than in the case of
using the water spraying system. Respirable dust concentration
is lower than MAC during longwall shearer cutting when
using the air-and-water spraying system. Dust concentration
at the operator’s workstation, when mining direction is
against the flow of fresh air is given in