Seat width and depth: The seat should have enough width and depth to support any user comfortably. Usually, 17-20 inches wide is the standard. The depth (from front to the back of the seat) needs to be enough so that the user can sit with his or her back against the backrest of the ergonomic office chair while leaving approximately 2 to 4 inches between the back of the knees and the seat of the chair. The forward or backward tilt of the seat should be adjustable.
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