Ergonomics - how to set up an office chair

Setting up | Driving a chair | Avoid the risks | The wider environment

Setting up a chair

Seat height:
Thigh to trunk angle at 90^o or slightly more to help keep pelvis upright
 
Back height:
Lumber to fit small of back to ensure
natural 'S' shape spine
 
Armrests:
Touching forearms when shoulders and elbows relaxed at the side to avoid strain in neck and upper limbs
 
Tension:
Floating when feet off the floor to encourage improved blood circulation and comfortable changes of posture (not too soft so you
instantly recline or too hard that you can't naturally push back )
 
Seat depth:
Bottom at back of seat and three fingers gap between front edge of seat and behind knees
to ensure adequate thigh support but without obstructing leg movement

How to drive a chair

The best ergonomic chairs can't do the job for you. Awareness and a little bit of training goes a long way.

• Try not to slouch
• Keep the chair unlocked most of the time
• Make full use of the chair movement - especially on phone or reaching behind you
• Alter position when typing - try upright for short periods
• Move your feet in front and behind - don't stay in the 90^o dummy position!
• Make the effort to adjust any other chair you sit on around the office

Why bother - The risks

The main risks are the health problems associated with VDU work, which include:

• Musculo - skeletal issues (upper limb disorders, back ache, RSI etc.)
• Eye strain and headaches
• Fatigue and stress

By ignoring the potential problems of poor or unadjusted seating, employers face having to deal with the following:

• Failure to meet DSE regs (designed to protect computer users - in force since end of 1992)
• Increased risk of criminal prosecution and/or claims for civil damages if you fail to comply
• Failure to save costs by allowing increased days off sick caused by work-related injury
• Increased likelihood of low morale and stress
• Reduced productivity and work quality

Adjusting the wider environment

Tactics for keeping an upright healthy posture

• Be aware of what your body is telling you and take action if you are uncomfortable
• Change posture and ideally have frequent breaks from the desk
• Keep the mouse and phone as close as possible allowing arms to be parallel to desk & relaxed thus avoiding postures which require a joint to be used for long periods at the end of its range of motion
• Avoid causing the upper limbs to be held in a raised position. Ideally adjust the desk and the chair to suit you. If not adjust the chair and use a foot rest
• Avoid twisted asymmetrical positions so operate the keyboard when directly in front of you
• Use a sturdy document holder to present reference material closer to you
• Minimize glare on the screen by removing or controlling light source eg using window blinds
• VDU screen should be placed approx. ½m or arms length from face
• Top of the screen should be approx. at horizontal line of sight. Try placing lap tops
  on a forward sloping surface to raise screen
• Rest eyes at infinity when not looking at screen (end of office or window)
• If writing or reading predominantly place material on a forward sloping surface of
  10 to 20^o
• Re-arrange items on your desk in order of frequency, function, importance or sequence
• Tidy trailing cables or other obstructions around desk
• Remove or control excessive noise or sources of heat and cold