5. Seat pan front edge
- The front edge of the seat pan in some chairs is not padded or contoured properly.
- If the front edge of the seat pan causes contact stress at the back of the knees, blood supply will be lacking and may result in numbness and/or cramping.
- The front edge of the seat pan should have a waterfall edge (gently sloping) with proper padding.
6. Back rest design
- The back rest in some chairs is too big, too small, or not the right shape.
- If the back rest doesn’t fit the back properly, there will be discomfort from pressure points and there may be a reduction in range of motion for the shoulders (when the back rest is too wide).
- The back rest should fit the back properly and be smaller at the top to allow for shoulder movement.