Step 3: Back and Legs

Your back should be firmly supported by the chair when you are sitting up straight with your thighs at right angles to your torso. The lumbar curve of the back should be supported as well. If the backrest does not provide lumbar support, use a pad or pillow. 

If the backrest angle is adjustable, make sure that the thighs and torso are at approximately a right angle when the feet are resting on the floor. If the backrest has tension adjustment, make sure that it is firm enough to support your back while working. It should only tilt back under force. 

Your lower legs should be at right angles to your thighs. Your upper legs should be positioned so that the knees are slightly above the hip. Your feet should be flat on the floor. If your lower legs are not at right angles to your thighs, your chair is too low. If your feet are not flat on the floor, your chair is too high. It may be necessary to use a footrest to support your feet and maintain the correct position relative to the keyboard. If your thighs are compressed on the seat pan, the chair is too high. Some chairs offer a seat pan tilt adjustment which will offer a greater range of fit. 

  • Chairs should be upholstered, have arms, castors, reasonably high backs, and be easily adjustable for height and tension.
  • Encourage employees to stand up occasionally while talking on the phone.