In-cabin Particulate Matter Exposure of Heavy Earth Moving Machinery Operators in Indian Opencast Coal Mine

Abstract

As a part of their occupation, the operators of heavy earth moving machineries (HEMM) working in opencast mines are exposed to several air pollutants, prominent one being the airborne particulate matter. The paper presents the findings from a study that was aimed at investigating the particulate matter exposure of heavy earth moving machineries (HEMM’s) operators in highly mechanized opencast mines. The HEMMs included in the study are dumper, shovel and drill. The mean in-cabin PM₁₀ concentrations of dumper and shovel, which had an air-conditioning system in the cabin, were in the range of 600–650 µg m⁻³. Operators inside the drill cabin that did not have air conditioning systems were exposed to as high as 1992 µg m⁻³ However, cabins were effective in preventing up to 20% particulate matter exposure by the operators in comparison to persons working in an open mine atmosphere. The main haul road in mines contributed ~ 50% higher exposure than the internal haul roads. Coarse particles (PM₁₀) are retained in upper respiratory tracts while the fines (PM_2.5 and PM₁) travel via tracheobronchial region and reach the alveolar region. Studies on occupational exposure of HEMM operators to different pollutants in a mine is at present very limited and therefore more studies need to be conducted.