Ergonomics: Design Principles or Axioms

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Ergonomics Design Principles or Axioms

• General Guiding Principles or Thought Processes
• Simple But Powerful Concepts
• All Detailed Design Goals and Objectives Derive
  From Basic Design Axioms
• Basic Design Axioms are More Important to
  Remember Than More Specific Solutions

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Ergonomics Design Principles for Workstations

• Do Not Lower That Which Must Be Lifted
• Do Not Lift That Which Must Be Lowered
• Use Gravity - Do Not Oppose It

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Design Principles and Rules of Thumb

• Provide Adequate Space to Turn the Whole Body
• Do Not Reach Behind
• Avoid Extremes of Joint Movement
• Avoid Postural Extremes

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Design Principles

• Allow Natural, But Changing Postures
• Avoid Static Loading of Muscles
• Preserve the Natural Curves of the Spine

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Design Principles

• Apply Force Dynamically, Conserve Momentum
• The Lower the Reach Target, The Better the
  Shoulder Posture
• Work Should Be 2 - 4 Inches Below Elbow Height,
  In General
• Do Not Lift the Elbow
• If Workers Must Reach Up and Out, Keep the Reach
  Below Heart Level
• Pivot Movement About the Elbow
• Keep Arm Motions Within the Normal Working Area

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Design Principles

• Give Support To the Body
• Avoid Contact Stresses
• Reduce Repetition (enlarge jobs, rotate,
  mechanize)
• Reduce Force
• Power With Motors - Not With Muscles
• Avoid Vibration - Especially Resonate Frequency
  Ranges

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Design Principles

• Provide Adjustability
• Fit a Range - Not the Average
• Accommodate As Wide A Range as Possible

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Design Principles

• Match the Tool to the Task
• Handles Should be Smooth, Non-Conductive, and
  Compressive
• Design For the Person With the Least Strength
• Match the Grip to the Worker Population
• Spread Contact Over Several Fingers - Not Just One

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General Approaches to Solving Ergonomics Problems

• Eliminate the Need for the Task
• Convert the Task to a Less Stressful Task
• Mechanize the Task
• Automate the Task - Assign the Task to a Machine

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Solving Ergonomics Problems Lifting

• Convert the Lift/Lower to a Push/Pull
• Convert the Lift and Carry to a Push/Pull
• Mechanize the Lift/Lower (Operator Guided,
  Machine Lifted)
• Automate the Handling Task