Ergonomy in work place

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Ergonomy in work place

• Ergonomy presentation
• Farnoosh Khodakarami
• Hengameh Vahabzadeh
• SupervisorMr.Ghayoor
• Fall 2006

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Ergonomy in work place

• Ergonomy
• Derived from the Greek ergon (work) and nomos
  (laws) to denote the science of work, ergonomics
  is a systems-oriented discipline which now
  extends across all aspects of human activity.
• Ergonomists contribute to the design and
  evaluation of tasks, jobs, products, environments
  and systems in order to make them compatible with
  the needs, abilities and limitations of people

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• Domains of specialization within the discipline
  of ergonomics
• - Physical ergonomics is concerned with
  human anatomical, anthropometric, physiological
  and biomechanical characteristics as they relate
  to physical activity.
• relevant topics working postures,
  materials handling, repetitive movements, work
  related musculoskeletal disorders, workplace
  layout, safety and health.
• - Cognitive ergonomics is concerned
  with mental processes, such as perception,
  memory, reasoning, and motor response, as they
  affect interactions among humans and other
  elements of a system.
• relevant topics mental workload,
  decision-making, skilled performance,
  human-computer interaction, human reliability,
  work stress and training as these may relate to
  human-system design.

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• Organizational ergonomics is concerned with the
  optimization of sociotechnical systems, including
  their organizational structures, policies, and
  processes.
• relevant topics communication, crew
  resource management, work design, design of
  working times, teamwork, participatory design,
  community ergonomics, cooperative work, new work
  paradigms, virtual organizations, telework, and
  quality management.

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• Work place layout
• work space Physical design of a workspace
  includes working out how much space needed, and
  positioning of furniture, tools, equipment and
  any other items needed to perform the tasks, in
  respect of posture, access, clearance, reach and
  vision of the user.
• work space factors
• What type of task will be carried out and what
  specific actions are to be used to complete the
  task?
• Will the potential users of the workspace (your
  user population) be seated or standing?
• What postures will the users have to adopt?
• What are the relevant body dimensions of the
  users? These dimensions can be found in
  anthropometric tables.
• Do you need to design using minimum, average or
  maximum dimensions?
• How far can the users reach, horizontally and
  vertically?
• What are the visual aspects of the task?

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• Body dimensions
• - Designing for the 'average
• - Designing for adjustability
• - Designing for extreme individuals
• The workspace envelope
• A 'workspace envelope' is a 3-dimensional
  space within which you carry out physical work
  activities when you are at a fixed location.

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• Visual workspace
• Frequently viewed items should be
  positioned within a comfortable zone in front of
  worker.
• This is normally within 15 above, or 30
  below, the horizontal, and 15 to the left and
  right.
• In the normal, relaxed position of the
  head, neck and eyes, the line of sight is about
  10 to 15 below the horizontal
• Distance is also a factor in visual fatigue.
• Visual displays are comfortably viewed from
  500-750mm or more

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Ergonomy in office work

• Features of an office such as people,
  space, equipment, furniture and the environment,
  must fit together well for workers to feel
  healthy and comfortable and to be able to work
  efficiently and productively.
• The Environment
• The environment, or surroundings, in which
  workers are working includes temperature,
  ventilation, humidity, lighting, noise etc
  factors.
• Lighting
• - Most people like to be able to see daylight
• - Natural light is thought to make people feel
  better
• - Monitors need to be positioned so that there
  is no glare or reflection on the screen.
• - Most people like to be able to control the
  artificial lighting levels in their work area.

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• Light Source
• The primary light source that man has relied
  on for thousands of years is the sun.
• The variation in light levels over the 24 hours
  of the day is important for two reasons
• - our bodies have natural rhythms
• - we appear to have a biological need for
  light
• Artificial light
• two main types of lamps used to provide
  interior lighting
• - incandescent light (light bulbs)
• - fluorescent tube
• Light Levels
• different tasks need different minimum
  amounts of light to be performed at a
  satisfactory level ( Ex. paperwork and screen
  work as screens emit their own light )
• Direction of light
• Glare

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• Temperature and ventilation
• A suitable physical climate is needed to
  feel comfortable and be efficient at work. The
  environment feels comfortable when you are barely
  aware of the climatic conditions. It is only when
  the temperature decreases or increases beyond
  your comfort limits that you become aware of
  discomfort.
• comfort zone
• 20-22ºC in winter
• 20-24ºC in summer

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• Noise
• Noise is any annoying, disturbing or unwanted
  sound.
• Noise effects on people
• irritate people
• interfere with verbal communication
• reduce working efficiency
• disturb sleep
• damage hearing.
• The effects of noise
• Deafness
• The main effect of noise is the development of
  deafness, especially when you are exposed to high
  levels of continuous noise. This may result in
  'noise-induced occupational deafness'.

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• Noise and performance
• Noise causes fatigue and loss of concentration
  and efficiency, resulting in a decrease in work
  output and an increase in the number of mistakes
  made
• The World Health Organisation (WHO) provides some
  guidance on acceptable levels of noise in the
  community.

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Why ergonomics is important in office?

• Injuries like
• WRULD work related upper limb disorders
• Recent studies suggest a condition called
  e-thrombosis, an ailment where blood clots form
  as a result of sitting for a long length of time,
  is growing among professionals with desk jobs
• Repetitive Strain Injuries (RSI).  
• Professionals who spend an extensive amount of
  time in front of computers are at high risk for
  Repetitive Strain Injuries (RSI).   These
  musculoskeletal disorders, including carpal
  tunnel syndrome, tendonitis, lower back pain and
  tension headaches,

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Posture at work

• Changing your posture throughout the day is
  positive because when you change postures, the
  loads of sitting shift to different parts of the
  body, allowing your body to recover from extended
  static postures.
• For most people, it is quite a challenge to
  maintain good posture while sitting in an office
  chair and working for long hours in front of a
  computer
• a surprising number of people sit at the front of
  their office chair and hunch forward in an
  attempt to get closer to their computer screen
• leaning forward 30 degrees in an attempt to get
  closer to the computer screen puts 3 to 4 times
  more strain on the back

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• Technique to avoid hunching while
• sitting in an office chair
• To avoid the natural tendency to hunch forward
  while sitting in an office chair and working at a
  computer, Place a tennis ball between the middle
  back and the office chair on each side of the
  spine
• if one does get absorbed into work and starts to
  lean forward the tennis ball will fall out,
  serving as a concrete reminder to stop hunching
  forward and straining the back.
• Because the mind senses the ball, it remains
  connected with the body instead of being
  completely absorbed by what is on the computer
  screen. Maintaining more awareness of the body
  allows one to more easily maintain better posture

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posture

• Your arms and legs Make sure that your upper arms
  are vertical (or close to it), and your forearms
  are horizontal (or close to it) so that there is
  approximately a right angle at your elbows
• your shoulders should be relaxed,
• your elbows should just about be level with the
  desk surface or very slightly above. If not, you
  should adjust your chair to get you to the height
  that allows this.
• Your head and neck Aim to keep your neck vertical
  and relaxed and your head upright.
• Look straight ahead at the screen, or slightly
  down (never up - too much muscle use!). Adjust
  the height of the screen if necessary.
• Adjust the distance of the screen so
• that you can read the characters
• Keep your wrists straight, in line with
• your forearms, and relaxed.
• The forearm and hand make up 5
• of an average body weight so
• improper positioning can result in fatigue

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Posture at work
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seat

• Saet
• Height
• The seat should be able to adjust until your
  thighs are
• parallel to theground.
• At a fixed-height work surface, the chair should
  be
• set at a height so the worker's elbows are level
  with
• the height of the workstation
• Saet pan
• The seat pan depth should be adjustable to
  provide a fist-width to three-finger gap between
  the back of the calf and the front edge of the
  seat pan.
• The seat pan should have a waterfall (rounded)
  front edge
• Sharp corners, even when theyre made of padding,
  increase the pressure on the backs of the thighs.
  A rounded front edge distributes the pressure
  over a larger area.

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BackrestThe backrest height should be adjustable
so the lumbar support can be fitted to the low
backThe backrest should mirror the shape of your
back to provide support. It should be able to
support the natural curve of the spine

• Armrests
• Armrests should be adjustable. They should allow
  the user's arms to rest comfortably and shoulders
  to be relaxed.
• They should be rounded on the edges.
• Optional most armrests are spaced too widely
  apart for the user to use them comfortably

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• Swivel
• Any conventional style or ergonomic office chair
  should easily rotate so the user can reach
  different areas of his or her desk without
  straining

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• Seat material.
• The material on the seat and back of the
  ergonomic office chair should have enough padding
  to be comfortable to sit on for extended periods
  of time. Having a cloth fabric that breathes is
• preferable to a harder surface.
• The chair should have at least 5 castors at the
  base to ensure stability
• Footrests If the feet cannot be firmly planted
  on the floor, then a footrest is required
  Footrests are way to shift postures or provide
  support for the feet if the chair cannot be
  loweredA footrest should be height adjustable.
  Adjust the footrest until the thighs are parallel
  to the floor /- 1-3 inches

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• Desks
• Desks are usually a standard height of about
  720mm. This is fine for most people but.
  Particularly short or tall people may need an
  adjustable-height desk
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• You need enough desk space for your paperwork, 
  the computer (monitor, keyboard and  mouse) and
  any additional equipment that you need to do your
  job. 
• The desk should not have any obstructions
  underneath like drawers or supports, that force
  you to sit in uncomfortable positions
• Some desks are 'radial' - L-shaped with a curve
  in the middle where you sit. These can be quite
  comfortable for computer work as you can have
  everything you need close at hand in an arc
  around you.

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• Keyboard
• The keyboard should be positioned
• directly in front of the monitor
• when the user's fingers are placed on
• the keyboard, the forearms should rest parallel
  to the floor with the upper arms hanging
  comfortably to the sides.
• The keyboard should not force the user's wrists
  into flexion. Constant flexion of the wrists will
  cause unnecessary muscle tension, which will
  often result in fatigue and injury
• Place your keyboard in front of you with enough
  room to rest your hands when you are not typing.

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MouseThe mouse should be positioned at the same
height as the keyboard.The user should be able
to access the mouse with their arm at a
comfortable 90 angle to eliminate any strain on
the shoulder.. Bring the mouse as close to the
keyboard as you can so that you don't have to
stretch to use it.

• Monitors
• The top of the screen should be at or below eye
  level
• 15 monitors are the minimum recommended size,
  though 17 monitors becoming increasingly common
• The monitor should sit directly in front of the
  user
• Adjust the distance of the screen so that you can
  read the characters clearly
• The viewing distance to the computer screen
  should be between 13 28 to minimize
  eyestrain. Lighting is also very important.   The
  monitor should be at a 90 angle to a window,
  where the light is least likely to produce a
  glare
• Visibility Keep the computer screen clean by
  wiping it very lightly when needed with a damp
  paper towel or monitor cleaning solution.

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•  Phones (Headsets)
•   Users who frequently use the phone and computer
  simultaneously or are on the phone for extended
  periods of time should consider a headset.
  Headsets reduce the tendency to cradle the phone
  and allow the user to work with both hands while
  conversing on the phone

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• Breaks
• Proper break periods are commonly overlooked when
  close to a deadline or in a period of intense
  work.   Taking the recommended ergonomics breaks
  will increase energy, productivity and comfort
  while decreasing stress
• Short Breaks every hour are recommended for
  workers to perform at peak ability and prevent
  injuries
•    Short, frequent breaks are more beneficial
  than longer, more infrequent ones.
• Sitting for more than an hour without moving can
  put stress on the body due to the static posture
  that you are forced to sustain
• Active breaks are a short time-out from typing or
  tasks being performing for an extended period of
  time. This is not a break from work, just a break
  from the activityThe user can get up and stretch,
  stand up while on the phone
• Eye Breaks are one of the most important breaks
  for workers who spend most of their day staring
  at a computer screen. Eyestrain is a major cause
  of tension headaches
• At least once an hour focus on an object that is
  at least 20 feet away. These few moments each
  hour can spare workers days of discomfort
• .  

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• Exercises
• a good exercise would be to stretch muscles that
  are opposing the ones that you normally use. This
  will allow you to achieve a balance within muscle
  groups.
• Roll your head in circles, stretching more toward
  each shoulder
• Eyestrain tip Blink often, and take frequent
  rest pauses close your eyes for a minute,
  refocus by looking away from your monitor at
  something in the distance, and roll your eyes up
  and down, left to right.

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• Thanks for your attention