Ergonomics

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Ergonomics

• Safe Work Australia Week 2009

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• What is Ergonomics?
• Ergonomics is the field of study concerned with
  finding ways to keep people safe, comfortable,
  and productive while they perform tasks at work.
• Proper ergonomic design of a workplace is
  necessary to prevent Occupational Overuse
  Syndrome.

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• Occupational Overuse Syndrome
• Occupational Overuse Syndrome (OOS) is the term
  given to a range of conditions characterised by
  discomfort or persistent pain in muscles, tendons
  and other soft tissues.
• OOS replaces the term, Repetitive Strain Injury
  (RSI), as repetition is only one of the factors
  that causes these conditions.

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• Symptoms of OOS
• The symptoms of OOS are many and varied but
  usually they start as a general ache or tingling
  in the affected body part that comes on after a
  period of work or at the end of the day.
• These symptoms, if untreated, may develop into
  constant pain or numbness.

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• Causes of OOS
• The following are some factors that cause OOS
• Poorly designed workstations or workplace layout
• Awkward work postures and movements
• Repetitive movement
• Use of excessive force when working
• Lack of skills, training and experience

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• OOS Statistics
• In the five years between 2004 to 2008, there
  were 232 insurance claims for OOS in the NT.
  Australia wide, there were over 17,000 claims.
• The 232 NT claims resulted in over 8700 work days
  lost over the five years.

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• Preventing OOS
• OOS may be prevented by
• Providing appropriate equipment and workstations
  for the job, such as ergonomically designed,
  adjustable furniture, chairs, desks and
  computers.
• Ensuring that the work area is arranged so that
  materials, equipment and controls can be easily
  reached without stretching or twisting.

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• Preventing OOS
• Providing training and information to employees
  about safe working practices, for example correct
  work methods and postures, the correct use of
  tools and equipment.
• Ensuring that hand tools for repetitive tasks are
  a comfortable size, shape and weight.
• Are well balanced with a comfortable grip and
  require no more than reasonable force to operate.
  

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• Ergonomics in the office
• The remainder of the presentation will cover
• Good seating
• Workstation setup
• Desktop equipment

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• Good seating
• The lower back is placed under far greater stress
  in the seated position than it is in standing.
  This is because the tendency for the natural
  inward curve of the back to flatten when poorly
  seated (fig 1).
• A good chair combined with an appropriate posture
  can significantly reduce stress and other
  problems that often occur as a result of
  prolonged sitting (fig 2).

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• Good seating
• What to look for when choosing a chair
• The chair needs to
• promote and support a natural and relaxed
  curvature of the back and a good working posture
  (ie. it needs some form of adjustable lumbar
  support)
• minimise muscle fatigue and impedance to
  circulation (ie. the seat itself should not be so
  long that it presses on the back of the legs. The
  front edge should be adequately padded)
• be able to be adjusted easily from the seated
  position and
• be stable.

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• Good seating
• A good office chair can make a real difference
  not only to the comfort and well-being of the
  desk worker but can also increase their
  productivity.

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• Workstation setup
• When setting up your workstation, the desk helps
  determine the placement of nearly all other
  equipment.

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• Workstation Setup
• If you have a height-adjustable desk
• Adjust your chair to suit your body size
• adjust the desk so the top surface is just below
  elbow height.

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• Workstation Setup
• To determine your elbow height, relax your
  shoulders and bend your elbows to about 90
  degrees
• check the elbow height against the desk height.

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• Desktop equipment
• Keyboard placement
• Place the keyboard as close to the front edge of
  the desk as is comfortable
• Do not place documents between the keyboard and
  the front edge of the desk while using the
  keyboard
• this increases the reach distance to the keyboard
  and may result in excessive bending of the neck
  to look at the documents.

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• Desktop equipment
• Screen placement
• The screen should be positioned once the chair
  and desk heights have been established.
• The height of the screen should be positioned so
  that the top of the screen is level with, or
  slightly lower than, your eyes
• place the screen so that it is approximately an
  arms length away from the usual seated position
  of the user and adjust as required.

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• Desktop equipment
• Clearance under the desk
• Items should not be stored under desks where they
  will decrease or interfere with the space
  required for the legs.
• Drawers
• Most commonly used items should be placed in the
  top desk drawer to improve access and reduce
  reaching and bending movements.

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• Desktop equipment
• General storage on desk
• In-trays and containers for stationery should be
  placed in the outer reach area (refer to figure)
  and in-trays should not be located above shoulder
  height.

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• Desktop equipment
• Reference books and folders
• Large or heavy references such as telephone
  directories and manuals should either be stored
  within close reach of the seated user or in a
  nearby position where the user has to stand to
  access them.
• Handling of these items should not be conducted
  at the limit of a persons reach capacity while
  sitting as this can result in undue strain on the
  back, shoulder and arm muscles.

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• Further information
• A range of Information Bulletins have been
  developed on the topic of ergonomics and is
  available at www.worksafe.nt.gov.au