What Is ERGONOMICS ? ? ?
• Ergonomics is derived from two Greek words:
ergon, meaning work; and nomoi, meaning
• Thus ergonomics means the science of work and
a person’s relationship to that work.
• Ergonomics is the science of making things comfy.
It also makes things efficient.
• Ergonomists study work, how work is done and
how to work better.
• Ergonomics is commonly thought of in terms of
products. But it can be equally useful in the
design of services or processes.
What is comfort ?
• Physical comfort : If you do not like to touch an item you won't. If
you do not touch it you will not operate it. If you do not operate it,
then it is useless.
• The utility of an item is the only true measure of the quality of its
• The mental aspect of comfort in the human-machine interface is
found in feedback.
What is efficiency?
• Efficiency is quite simply making something easier to do.
• Reducing the strength required makes a process more physically
• Reducing the number of parts makes repairs more efficient.
Types of ergonomics :
• Physical ergonomics: the science of designing user
interaction with equipment and workplaces to fit the
• 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.
• Organizational ergonomics is concerned with the
optimization of socio-technical systems, including their
organizational structures, policies, and processes
Principles of ergonomics :
1. Work in Neutral Postures.
2. Reduce Excessive Force.
3. Keep Everything in Easy
4. Work at Proper Heights.
5. Reduce Excessive Motions.
6. Move, Exercise, and Stretch.
7. Maintain a Comfortable
Ergonomic injuries :
Ergonomic injuries are those injuries caused by the presence
of ergonomic risk factors.
Ergonomic injuries may be referred to as :
• Repetitive Stress Injuries (RSIs),
• Repetitive Motion Injuries (RMIs),
• Musculoskeletal Disorders (MSDs),
• Cumulative Trauma Disorders (CTDs), or
• Cumulative Trauma Injuries (CTIs).
Common causes of MSD :
• Repetitive and/or prolonged activities
• Awkward postures/positions for an extended time
• Static postures
• High/low Temperatures for an extended time
• Forceful exertions
Signs and symptoms of MSD :
• Pain in the fingers, wrists, or other parts of the body
• Numbness, particularly in the hands or fingers
• Swelling, inflammation, or joint stiffness
• Loss of muscle function or weakness
• Discomfort or pain in the shoulders, neck, or upper or lower
back , etc.
Ergonomic controls :
– Modify the tool or work area
– Don’t do one thing too long
• Work Practices
– Use the right tool
Administrative control :
• Employee rotation/job task expansion
• Physical adjustments to the work place
• Redesign of work methods
• Alternative tasks
Work Practice control :
• Safe & proper work techniques & procedures
• Physical conditioning period