Assessment of Physical Workload and Musculoskeletal Disorder Risk in Upper Limbs of Painters

• Main Authors: Ting-Fang,He, 何廷芳
• Other Authors: Hsieh-Ching,Chen
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/3e4ax5

碩士 === 國立臺北科技大學 === 工業工程與管理系碩士班 === 103 === Previous investigations show that many painters suffer from occupational diseases such as tennis elbow and rotator cuff syndrome. Such finding indicates that painters have high risk of musculoskeletal hazards in their upper extremities. This study conducts three simulated painting tasks, wall painting, ceiling painting, and paint scraping/paste filling, to measure subjective and objective workload while performing the tasks. Four ergonomics tools, including OCRA Index, HAL-TLV, KIM-MHO, and EAWS4 were used to evaluate the upper limb risk of musculoskeletal hazard in performing each task. This study combined a short range interactive projector and 4 WiiFit force plates to set up the control environment for simulation experiment. The interactive projectors are placed on a hydraulic wheel cart with adjustable table-height. According to the simulation task, the projector was adjusted to project on wall, ceiling or the 4 WiiFit fixed on an erected aluminum frame parallel to the wall. A computer system was used to control the test environment by continuously reading the brush coordinates sending from the interactive projector, or the scraping forces and center of resultant force sending from the WiiFit system. The brush coordinates in the projection screen were measured by the interactive projector with an infrared device fixed on the brush head. The computer system provides instantaneous feedback by translating force magnitude into color depth and superimposes its “magnitude” onto the corresponding location. In performing each experimental task, EMG, ECG, and Borg CR-10 of 15 male (23.4±1.1 yrs) and 15 female (22.4±1.2 yrs) participants were measured as the workload index. Experimental results show the 50th percentile EMG in subject&;#39;s dominant deltoid (wall and ceiling painting) and trapezius (wall painting and paint scraping/paste filling) are closed to or over 15% MVC. More than 50% of subjects have discomfort degree ≥ 2 (range 0-5) in their dominant shoulder and upper arm. Quantitative physical data shows that all tasks can result in high workload and is consistent with the subject workload (Borg CR-10: 4.7~5.9). Risk scores evaluated by the four ergonomic tools have good correlation with Borg CR-10 (all Pearson r&;gt; 0.8). According to assessment result, the paint scrapping/paste filling task has the highest risk among all tasks, and its’ risk level is “high risk”.