Postural Risk Assessment in Construction Using Rapid Entire Body Assessment (REBA) and Ovako Working Posture Analysis System (OWAS)

Abstract

Detailed postural assessment is crucial in the construction sector due to the high physical demands, awkward positions, and repetitive manual tasks that contribute to work-related musculoskeletal disorders (WRMSDs). This study aimed to evaluate ergonomic risk levels and their association with musculoskeletal discomfort among Malaysian construction workers using an integrated approach combining the Rapid Entire Body Assessment (REBA) and the Ovako Working Posture Analysis System (OWAS). Integrating both tools provides a comprehensive assessment as REBA captures task-specific biomechanical loads, while OWAS reflects cumulative postural stress during static and dynamic tasks. A cross-sectional study was conducted at four construction sites involving 106 workers. Musculoskeletal discomfort was assessed using the Nordic Musculoskeletal Questionnaire (NMQ), capturing symptoms over the past 12 months and 7 days. Postural risks were quantified using two complementary ergonomic tools the Rapid Entire Body Assessment (REBA) and the Ovako Working Posture Analysis System (OWAS)through video analysis and structured field observations. Within the past 7 days, the most reported musculoskeletal symptoms were localized to the lower back (64.2%), wrists/hands (50.8%) and shoulders (49.1%). REBA analysis revealed that 73.6% of workers were exposed to high to very high ergonomic risk, with fibre installers exhibiting the highest mean score (11.2 ± 2.1). OWAS evaluation indicated that 58.4% of observed postures fell into Action Categories 3 or 4, signifying a need for prompt corrective intervention A strong positive correlation between REBA and OWAS scores (r = 0.61, p < 0.01) demonstrated consistent identification of postural risks, particularly among ironworkers and carpenters. Chi-square analysis further confirmed significant associations between elevated ergonomic risk levels and reported discomfort in the lower back and shoulders (p < 0.05). The integrated use of REBA and OWAS provides a robust ergonomic evaluation framework that can guide targeted interventions and inform policy to reduce WRMSDs among construction workers.