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The key to sitting comfortably is to make sure that your body has the support it needs to maintain a “neutral posture.” Neutral postures put the least amount of stress on your body during your work tasks.

For seated tasks, like working on a computer, you can achieve neutral postures by making sure that your chair is adjusted to provide support for your back, legs and feet.

Remember that even sitting with perfect posture can cause fatigue, so be sure to take occasional breaks to stand and stretch.

Need help selecting a new chair?

OSH can assist DPH units with chair purchasing information. For more information about this service, please contact us at 554-2793.


Occupational Safety & Health

Sitting Smarter:
Things to consider before buying a chair


One size does not fit all

Even the most adjustable chair will not fit every body. You may need to select several models if buying for a group.

Try it before you buy it

Try a chair first, before you purchase it to make sure it provides you with adequate support to match your body and work tasks. Learn how to use all the adjustments on the chair and adjust it to fit you.

Don’t be fooled by advertisers who describe their chairs as "Ergonomic." There are no guidelines that prohibit anyone from calling anything "ergonomic," even if it has minimal adjustments.

Look for chairs with these adjustments

Seat Height

  • Adjust low enough so that your feet are flat on the floor and thighs are parallel to the floor.
  • Use a footrest for support if your chair does not go low enough or if you must raise your chair to comfortably reach desk height.
  • Feel pressure beneath your thighs or do you rest your feet on the legs of the chair? You may be sitting too high: lower your chair or get a footrest. Phonebooks and boxes make great footrests.

Seat Tilt

  • Useful for users who perform forward seated tasks, such as writing.
  • Adjust so that you can maintain comfortable body position depending on task.
  • For writing tasks, a slight forward tilt may be useful. For computer tasks, a neutral or slight negative tilt may be preferred.

Seat Size

  • If the chair seat is too deep, the back of your knees may hit the front edge of the seat.
  • Try using a lumbar support to push your forward.

Backrest Height

  • This allows the user to adjust the position of the lumbar support. You must sit against the backrest to support your lower back (lumbar area).
  • Raise or lower the backrest so that the most curved section of the backrest fits into your lower back.
  • Need more support? Make your own lumbar support by using a rolled up towel, bubble-wrap or small pillow.

Backrest Angle

  • Adjust so that your upper body and thighs create a 90-110 angle.

Cushioned Arm Rests

  • Make sure arm rests are adjustable for height and width and can be removed easily if not desired by the user.
  • Adjust so that armrests do not interfere with your ability to get close to your desk.
  • Lower or remove armrests that keep you from working with arms comfortably at your side.