Field comparison of rigid and soft passive back-support exoskeletons: physical exertion, comfort, and adoption among masonry workers

• Soft exoskeletons outperformed rigid designs in reducing perceived physical exertion for masons. • Comfort and usability predict willingness to use exoskeletons more than physical benefits. • Movement hindrance showed strongest correlation with rejection of exoskeleton adoption. • Workers prioritize unhindered movement and comfort over maximum physical support. Musculoskeletal disorders affect 46% of construction workers, causing major economic and organizational challenges. Despite the promise of wearable exoskeletons for mitigating strain, limited on-site comparative research exists, particularly across distinct designs. This study addresses that gap by evaluating two back-support exoskeletons, HAPO Back (rigid) and BISKO (soft textile-based), in realistic masonry tasks. Fifteen masons from five sites tested both exoskeletons over two days through structured interviews, yielding noticeable strain reductions relative to baseline conditions. BISKO reduced perceived fatigue by 50.53% and perceived exertion by 32.57%, outperforming HAPO’s 27.39% and 14.76% reductions, respectively. BISKO also excelled in comfort (35.94% better) and adjustability (49.11% better), resulting in significantly less movement hindrance. Contrasting acceptance patterns emerged: HAPO users reported a 158% drop in continued-use willingness, whereas BISKO showed only an 8.52% decline. Correlation analysis highlighted movement hindrance (r = 0.79) and adjustability (r = 0.76) as stronger predictors of ongoing use than physical benefits alone. These findings underscore the importance of lightweight, worker-friendly designs that integrate well with dynamic construction tasks. This research challenges conventional exoskeleton development that focuses primarily on mechanical load reduction. The field-based approach provides insights under actual working conditions, offering practical guidelines for future product development and adoption strategies. Ultimately, prioritizing comfort and usability emerges as a decisive factor for sustained exoskeleton usage, reinforcing the critical role of human-centered designs for construction ergonomics. Such emphasis is especially crucial for masons, whose tasks involve varied postures and material handling. Future studies should expand these comparisons to other trades to refine exoskeleton design guidelines.