Ergonomics is the study of human interaction with products, processes, and systems to optimize safety, comfort and productivity. Good ergonomic design considers human abilities and limitations, such as force, flexibility, sight and hearing. Poor ergonomic design can lead to repetitive motion injuries by requiring unnatural movements or excessive force over long periods. Key principles for ergonomic design include adjusting workstations to appropriate heights, limiting twisting and bending, reducing noise and glare, and allowing for rest breaks to prevent injury.

1. Ergonomics

2. What is Ergonomics
Ergonomics is the study of
human safety and comfort factors
related to our interaction with, and use of,
products, processes and systems.

3. The study of ergonomics influences designers to
ensure that designs of
products, process and systems
are comfortable, functional, safe and user friendly.
Ergonomic Design

4. Good ergonomic design reflects normal
human movement and abilities.
Ergonomic Design

5. Poor ergonomic design requires people to
adapt to unnatural movement and activity
which may lead to injury.
Ergonomic Design

6. The most common problem of poor ergonomic design in the
workplace is Repetitive Motion Injury (RMI).
Ergonomics and Health & Safety.
RMIs are injuries are often in aching
muscles and joints that can result in
long term health problems.

7. Ergonomic Design Considerations
Important considerations for ergonomic design include
the following human capabilities:
• Force - The human ability to push, pull and lift
• Sight- The human ability and care of sight
• Hearing- The human ability and care of hearing
• Flexibility- the human ability to bend, twist and turn

8. Ergonomic Design Considerations
Important considerations for ergonomic design include
the following human capabilities:
Of the 4 design considerations,
force, flexibility, sight and hearing,
force and flexibility
are the main focus of ergonomic design as these considerations
lead to the most common workplace injuries called
Repetitive Motion Injuries (RMIs).

9. Ergonomic Design and Force
Considerations for ergonomic design:
• Force - The human ability to push, pull and lift
Designers must consider the following workplace
demands:
• What must be pushed, pulled or lifted, how much will it weigh
and how is it to be pushed, pulled or lifted.

10. • How much do the objects weigh?
• Can heavy loads be made into a few lighter ones?
• Can be safely lifted by one person?
• Is the object too awkward to be lifted and carried alone?
• Is there a way to minimize the amount of lifting and carrying
(i.e. – is there a device, such as a wheeled cart, to use to carry the object)?
Ergonomics and Force
The first step in ergonomic design and force is assessing the
objects to be lifted:
Attempting to lift a heavy object all at once may result in back injury.

11. General Lifting Principles:
• Lift by bending your legs, not your back.
• Keep the object close to you (close to your centre of gravity).
• Use handles if possible (to get a better grip on the object).
• Get assistance if the object is large or awkward (even if it is light).
Ergonomics and Force
Lifting Heavy Weights

12. Graphic representation of the correct way to lift a heavy object

13. Ergonomic Design and Flexibility
Considerations for ergonomic design:
• Flexibility- the human ability to bend, twist and turn
Designers must consider the following workplace
demands:
• How much bending, twisting and turning is required

14. • Select tools that can be used without
bending the wrist.
• Hand tools should allow the operator
to grasp, hold, and use the tool with
the wrist held straight.
Ergonomics and Flexibility
Hand tool use can often result in Repetitive Motion Injuries (RMIs)
The following rules should be applied to hand tool usage:

15. • 5-10 cm below elbow level for precision
work such as reading or writing.
• 10-15 cm below elbow level for light
work such as working at a kitchen
counter.
• 15-40 cm below elbow level for work
requiring downward force such as
cutting or drilling.
Workstations for working in a standing position should be
adjusted as follows to avoid RMIs:
Ergonomics and Flexibility

16. The best ways to prevent an RMI may include:
• Try to use a workstation that is the right height for you.
Working in awkward postures for long periods of time can lead to RMIs.
• Try to stretch or go for a walk.
Working in the same posture for a long time can also lead to RMIs.
• Try to vary the types of movements you do.
Use a variety of muscle groups.
• Try to use only the amount of force necessary.
Applying excessive force repetitively and for long periods of time can cause injury.
• Pace your work.
Working at a fast pace for a short amount of time may be worse than a slower pace
for a longer period of time.
• Make sure your body has time to recuperate.
Working long hours without taking time to recuperate (rest breaks) can also lead to injury.
Ergonomics and Flexibility

17. Summary of rules to prevent
Repetitive Motion Injuries
(RMIs)
Ergonomics and Flexibility

18. Ergonomic Design Considerations
Considerations for ergonomic design:
• Sight- The human ability and care of sight
Designers must consider the following workplace
demands:
• What must be clearly seen, what is the required field of vison
and how much light will be required for clear vision.

19. Sight considerations in ergonomic design include efficiency but are,
above all, required to ensure the safety of a worker’s eye sight and
the worker’s ability to see and recognize potential safety hazards.
Ergonomics and Sight

20. Ergonomics and Sight
Ergonomic design for sight in the workplace must include
proper lighting to avoid eye strain over a long period.

21. Ergonomics and Sight
Computer screen glare is a concern for workers working with
computers for many hours each day.

22. Ergonomics and Sight
Ergonomic design considerations
also focus on line of sight.
Workers must have a clear line of
sight for safety and efficiency.

23. Ergonomic Design Considerations
Important considerations for ergonomic design include
the following human capabilities:
• Hearing- The human ability and care of hearing
Designers must also consider the following common
workplace demands:
• What sounds must be heard and what noise must be limited

24. Ergonomics and Hearing
Ergonomic design considerations include reducing noise in a
work environment. Sound dampening and sound reducing
products may include:
• Acoustic ceiling tiles
• Carpeted floors
• Wall mounted sound absorbing systems

25. Ergonomics and Hearing
Ergonomic design of processes must often also
include hearing protection equipment.

26. Ergonomics and You
Use ergonomic considerations and design in your
daily activities and routines will help prevent RMIs,
long term injury or health problems.

27. Ergonomics and You
Medical terms for Repetitive Motion Injuries (RMIs) that may
result in long term health problems include:
• Cumulative Trauma Disorders (CTDs)
• Carpal tunnel syndrome – injury in the wrist
• Bursitis – injury in the “bursa” – a part of the joints
• Tendonitis – injury in the tendons
These health problems are preventable with good ergonomic
practices.

28. Ergonomics and You
Always practice good posture.

29. Ergonomics and You
Always bend your knees and use your legs
to lift heavy objects.

30. Ergonomics and You
Get up and stretch or move after long periods of
time in a stationary position.

31. Ergonomics and You
Protect your eyesight and hearing.

32. Ergonomics and You
Always observe and practice good safety habits and rules.