Review the Existing Vertical Fit
Backrest height remains unchanged, so begin by assessing its position relative to the person seated in the chair. Confirm relevant dimensions and examine where the backrest contacts the body. Avoid treating a general height measurement as a complete description of support; the shape and position of contact also need direct assessment.
Ask users to describe their sitting position during an ordinary activity. Note whether they remain against the backrest or move away to reach equipment. These observations help explain how the existing backrest arrangement works in practice and whether a finding relates to the chair, the person or the surrounding workstation.
Clarify How the Lumbar Support Is Configured
Lumbar-support office chairs without back-height adjustment can only be compared accurately when the support arrangement is understood. Its presence does not establish independent height or depth adjustment. Confirm any such controls directly before discussing the amount of personal positioning available to users.
Evaluate the support in the position used for work, rather than relying on a visual inspection of the empty chair. If separate support adjustment is confirmed, test it on its own terms and record the result. Keep that assessment distinct from backrest height, which cannot be changed through a height control in this combination.

