Rapid Upper Limb Assessment (RULA) for Ergonomic Decision Making in Welding Postures

Awkward welding postures were commonly associated with high ergonomic risk, but changes in Rapid Upper Limb Assessment (RULA) scores could also have reflected observer variability. This experimental study assessed whether RULA improvements after ergonomic intervention exceeded observed scoring variability. Sixteen welding conditions, including flat, horizontal, vertical, overhead, fixed-pipe, 45°-pipe, and site-constrained tasks, were evaluated before and after interventions involving work-height adjustment, workpiece rotation, arm support, ergonomic seating, and stable platforms. Observer variability was quantified from 40 RULA assessments of five reference postures. The mean RULA score decreased from 6.56 ± 1.03 to 3.88 ± 1.26, representing a 40.9% reduction. Ergonomic risk decreased in 15 of 16 conditions, and the number of maximum RULA scores of 7 decreased from 12 to zero. Exact observer agreement was 60.0%, with a mean absolute error of 0.575 and a 90th-percentile error of 2 points. These findings indicated that RULA provided stronger evidence of ergonomic improvement when score reductions exceeded observer-related variability.

RULA; welding ergonomics; awkward posture; workstation redesign; musculoskeletal risk

1. McAtamney, L., & Corlett, E. N. (1993). RULA: A survey method for the investigation of work-related upper limb disorders. Applied Ergonomics, 24(2), 91–99. https://doi.org/10.1016/0003-6870(93)90080-S [Google Scholar] [Crossref]

2. Salleh, K. F., Mohd. Fadzil, S., & Md. Daud, M. Y. (2023). Ergonomic posture assessment approaches for new welder: A study in technical institution. Jurnal Kejuruteraan, 35(5), 1045–1054. [Google Scholar] [Crossref]

3. https://doi.org/10.17576/jkukm-2023-35(5)-06 [Google Scholar] [Crossref]

4. Hamizatun, M. F., Haikal, S. A., & Nik Mohamed, N. M. Z. (2023). Ergonomic embedded in designing welding assembly tool for automotive manufacturing process. Journal of Modern Manufacturing Systems and Technology, 7(2), 23–30. https://doi.org/10.15282/jmmst.v7i2.9923 [Google Scholar] [Crossref]

5. Azrin, M. S. M., Jiovanny, J., & Khamis, N. K. (2023). Preliminary study on ergonomic posture analysis and environmental stress exposure toward staff in welding bay. AIP Conference Proceedings, 2544(1), 040025. https://doi.org/10.1063/5.0134757 [Google Scholar] [Crossref]

6. Nowara, R., Holzgreve, F., Golbach, R., Wanke, E. M., Maurer-Grubinger, C., Erbe, C., Brueggmann, D., Nienhaus, A., Groneberg, D. A., & Ohlendorf, D. (2023). Testing the level of agreement between two methodological approaches of the Rapid Upper Limb Assessment (RULA) for occupational health practice—An exemplary application in the field of dentistry. Bioengineering, 10(4), 477. https://doi.org/10.3390/bioengineering10040477 [Google Scholar] [Crossref]

7. Ogedengbe, T. S., Abiola, O. A., Ikumapayi, O. M., Afolalu, S. A., Musa, A. I., Ajayeoba, A. O., & Adeyi, T. A. (2023). Ergonomics postural risk assessment and observational techniques in the 21st century. Procedia Computer Science, 217, 1335–1344. https://doi.org/10.1016/j.procs.2022.12.331 [Google Scholar] [Crossref]

8. Chandra, A., & Arora, P. K. (2024). Study on ergonomic risk assessment of welding workers using RULA. Evergreen, 11(2), 1240–1247. https://doi.org/10.5109/7183430 [Google Scholar] [Crossref]

9. Martins, D. R., Cerqueira, S. M., & Santos, C. P. (2024). Combining inertial-based ergonomic assessment with biofeedback for posture correction: A narrative review. Computers & Industrial Engineering, 190, 110037. https://doi.org/10.1016/j.cie.2024.110037 [Google Scholar] [Crossref]

10. Agostinelli, T., Generosi, A., Ceccacci, S., & Mengoni, M. (2024). Validation of computer vision-based ergonomic risk assessment tools for real manufacturing environments. Scientific Reports, 14, 27785. [Google Scholar] [Crossref]

11. https://doi.org/10.1038/s41598-024-79373-4 [Google Scholar] [Crossref]

12. Cherry, N., Beach, J., & Galarneau, J.-M. (2025). The relation of musculoskeletal disorders to ergonomic work demands in welders and electrical workers: A prospective Canadian cohort study. Annals of Work Exposures and Health, 69(6), 626–640. https://doi.org/10.1093/annweh/wxaf029 [Google Scholar] [Crossref]

13. Alam, M. D., & Khan, I. A. (2025). Optimization of ergonomic parameters in overhead arc welding using grey relational analysis. Journal of Biomechanics, 189, 112823. [Google Scholar] [Crossref]

14. https://doi.org/10.1016/j.jbiomech.2025.112823 [Google Scholar] [Crossref]

15. Tanthuwapathom, R., Manupibul, U., Jarumethitanont, W., Limroongreungrat, W., Ongwattanakul, S., & Charoensuk, W. (2025). Reliability of sitting posture between physical therapist video-based evaluation and SMART IMU system using rapid upper limb assessment (RULA). Scientific Reports, 15, 1441. https://doi.org/10.1038/s41598-025-85159-z [Google Scholar] [Crossref]

16. Naranjo, J. E., Mora, C. A., Bustamante Villagómez, D. F., Mancheno Falconi, M. G., & Garcia, M. V. (2025). Wearable sensors in industrial ergonomics: Enhancing safety and productivity in Industry 4.0. Sensors, 25(5), 1526. https://doi.org/10.3390/s25051526 [Google Scholar] [Crossref]

17. Tasik, S. A., Maulidya, R., Utami, I. W., Safitri, D. M., Rahmawati, N., & Habyba, A. N. (2025). Integrating ergonomic intervention and digital human modelling for posture improvement in welding tasks. Journal Industrial Servicess, 11(2), 278–289. https://doi.org/10.62870/jiss.v11i2.31507 [Google Scholar] [Crossref]

• Impact of Foreign Direct Investment in India
• Issues Involved in Digitalisation Special Reference to Indian Tourism Growth
• Relationship Marketing and Customer Loyalty in the Fast-Moving Consumer Goods (FMCG) Industry in Nairobi County
• Financial Literacy or Financial Inclusion? Which is Which, What is What—To Achieve Uganda’s 10-Fold Economic Growth By 2040
• Harnessing Natural Gas for Economic Transformation: Overcoming the Regulatory and Infrastructural Bottlenecks in Nigeria