RISK ANALYSIS OF VIBRATION AND POSTURE TO MUSCULOSKELETAL DISCOMFORTS OF UNDERGROUND MINE DRILLING WORKERS
Undergound drilling workers who used jeg leg drill machine have musculoskeletal discomfort risk due to exposure of vibration and ergonomy factors. The purpose of this research is to analyze the risk of vibration and posture to musculoskeletal discomfort of drilling workers.Vibration measurement using Human Vibration Meter based on ISO 5349-2. Posture observation using BRIEF and QEC survey. musculoskeletal complaints by Cornell Musculoskeletal Discomfort Questionnaire. The measurement result showed that the average value of daily vibration exposure were exceed the threshold by range 11.0 to 21.62 m/s2. Hbeam installation was the highest risk task based on BRIEF and QEC survey .The prevalence of complaints of the drilling workers was greater (100%) than controls (55%). Musculoskeletal discomfort were include discomfort, tingling, cramps, numbness and pain. The most complaints in hand was in A (62.5%) and B (45.8%) right hand area, and for the body was low back (62.5%). The frequency of complaints was generally 1-2 times last week (48.5%). Total of 57.1% of complaints are categorized as slightly uncomfortable and 85.7% the workers stated that the discomfort did not interrupt their job. According to statistical analysis, age and years of work have a significant correlation to musculoskeletal discomfort on hand and body. Based on statistical analysis, it could be concluded that the regression equation for musculoskeletal discomforts on hand using BRIEF and QEC methods were qeuialent, while the assessment of musculoskeletal discomforts on body need more homogenous group of age.