Summary
Adjustable office chairs can help people sit comfortably, but only if users can easily operate the adjustment controls and the chair supports different postures during work. The authors tested two popular office chairs with 20 people to see which controls were easier to use and how comfortable the chairs felt during a task that required changing positions. They found one chair was easier to adjust overall, especially for certain controls like the headrest and armrests, while the other was easier to adjust seat height. Although discomfort was similar, users were more satisfied with some parts of the first chair. These findings highlight design features that can make office chairs better for dynamic work.
What this means in practice
- •For office furniture designers: Design adjustable chair controls that balance ease of use with effective support for changing postures in multi-device office work.$Commercial implications: This paper identifies specific control designs that improve usability and satisfaction, enabling manufacturers to build higher-quality ergonomic chairs.
- •For workplace ergonomics consultants: Recommend office chairs with proven control usability and support features to improve comfort and satisfaction in dynamic office tasks.
Authors
Yejin Kang, Dusan Baek, Dongwoo Park, Kitae Hwang, Woojin Park
Abstract
Adjustability is a core determinant of ergonomic fit in office chairs, but its benefits depend on users being able to operate the controls and, on the chair, continuing to support the body as posture changes during work. We compared two high-end office chairs, the T90 (Sidiz; Chair A) and the Aeron (Herman Miller; Chair B), in two experiments to explore which design features may explain differences between them. In Experiment 1, 20 participants adjusted ten controls common to both chairs and rated perceived adjustment difficulty on four items. Chair A had significantly lower overall difficulty (Wilcoxon signed-rank test, p = 0.008), with control-level advantages for headrest angle, armrest height, armrest rotation angle and lumbar support position; Chair B was easier for seat height, possibly because its side-mounted lever is more visible than Chair A's underside button. The headrest comparisons involved a third-party headrest fitted to Chair B, and control- and item-level tests were not corrected for multiple comparisons. In Experiment 2, the same participants completed a 15-minute multi-device task requiring repeated posture changes, reach and reorientation, then rated body-part discomfort, general comfort and satisfaction with five components. Discomfort and comfort did not differ; Chair A had higher satisfaction for the seat-pan and lumbar support (exploratory, uncorrected). Interviews suggested links to mechanism properties: Chair B's rear lumbar dial was often described as producing little perceptible change, and for controls without significant differences each chair appeared to leave a different aspect of the same need unmet. These findings suggest mechanical and interface properties that designers of adjustable office chairs may consider for dynamic, multi-device work.