Assessment of Whole Body Vibration Exposure of Hemm Operators in Mechanized Opencast Mines

Abstract

Whole body vibration (WBV) is accepted as an occupational health hazard for different HEMM operators and is an emerging health related issue in mining industry. The purpose of the current study is to assess the WBV exposure level of HEMM operators in opencast mines and compare the WBV levels against the ISO standards. The WBV was measured in accordance with ISO 2631-1:1997 using a tri-axial seat pad accelerometer placed at the interface of seat/operator and the data is recorded by the instrument named human vibration monitor (HVM)-100.
The WBV experienced by operators had steady state vibration and jolts or shocks. In Lakhanpur OCP coal mines, results showed that the frequency weighted RMS value of 773D-470dumper’s operatorhad experienced exposure level that exceeded the Exposure Limit Value (ELV)and it was 1.14 m/s2 and for VDV the highest exposure level was experienced by the operator of the same dumper was 18m/s1.75. The operators of BH-100 dumper 1116 and BD 355 dozeralso experienced the VDV exposure level more than recommended ISO, ELV. It wasalso observed that the weighted RMS acceleration and VDV values along Z-axis weredominant for dumpers as compared to X-axis and Y-axis. In Noamundi opencast iron ore mines, The exposure of overall A(8) for different machinery operators were ranging from 0.05 m/s2 to 1.17 m/s2. The highest exposure level was experienced by the operators of dozers and dumpers. The operator of Dozer D275A was exposed to 1.17 m/s2 of A(8) value while, the operator of dumper Komatsu-01 experienced 0.92 m/s2 for loaded condition and 1.01m/s2 for unloaded condition and VDV for different machineries were ranges from 1 m/s 1.75 to 26.7 m/s1.75. The operator of dumper Komatsu-01 experienced the highest VDV exposure i.e. 26.7 m/s 1.75 for unloaded condition and 20.7 m/s1.75 for loaded condition. It has been also established that unloaded dumper operators are more likely to be exposed to the higher levels of WBV. These results may be used for providing the safe working environment to ope rators and also help in framing the recommended guidelines regarding WBV for Indian mines.