EVALUATION OF MANUAL LIFTING AND LOWERING ACTIVITIES USING REVISED NIOSH LIFTING EQUATION: A CASE STUDY AMONG AUTOMOTIVE ASSEMBLY WORKERS
Mohd Zubairy SHAMSUDIN1,2 and Nurshahirah MOHD SHAHID1
1Department of Health Sciences, Faculty of Engineering and Life Sciences, Universiti Selangor, 40000, Shah Alam, Selangor, Malaysia
2Centre of Occupational Safety and Health Risk Management, Universiti Selangor, 45600, Bestari Jaya, Selangor, Malaysia
Corresponding author: firstname.lastname@example.org
Workers in the automotive industry are exposed to various manual material handling activities that lead to Work-related Musculoskeletal Disorders (WRMSDs). Lifting and lowering loads are the main activities in the development of low back pain among the workers. A cross-sectional study was conducted to calculate Recommended Weight Limit (RWL) and Lifting Index (LI) for the selected lifting and lowering activities and to determine the prevalence of WRMSDs symptom among the workers. 120 male subjects were selected through purposive sampling. Standard Nordic Questionnaire (SNQ) was applied to identify WRMSDs. Meanwhile, NIOSH Revised Lifting Equation (NRLE) was used to evaluate job activities. Recommended Weight Limit (RWL) and Lifting Index (LI) for lifting and lowering tire were 11.78 kg (RWL origin) and 13.32 kg (RWL destination); 0.67 (LI origin) and 0.60 (LI destination) respectively. Meanwhile, RWL and LI for lifting front car bumper were 4.13 kg (RWL origin) and 3.72 kg (RWL destination); 1.40 (LI origin) and 1.08 (LI destination) respectively. The highest musculoskeletal disorder prevalence was lower back (39%), followed by shoulder (14%), upper back (11%), elbow (11%), neck (7%), wrist/hand (7%), ankle/feet (7%) and knees (7%). The study revealed the weight handled by workers for both activities were lower than RWL except RWL (destination) for the lifting and lowering front bumper. Meanwhile, LI for lifting and lowering tire was lower than 1.0 indicates the risk was nominal. However, LI for lifting and lowering front bumper was greater than 1.0 poses the condition of the activity more likely to cause risk for a majority of healthy workers. Necessary intervention must consider includes reducing vertical and horizontal distances, eliminated repetitive lifting and lowering and used applicable mechanical aids if necessary.
Keywords: Lifting; Lowering; NIOSH Revised Lifting Equation; assessment