What is ergonomics?
Ergonomics is the study of physical and mental
stresses on workers resulting from operation or
interaction with machines.
What are the goals of
▸ Prevent accidents, eg:
▸ good design of machine guards
▸ design of slip – resistant surfaces.
▸ Prevent fatigue, eg:
▸ design of a VDT (video display
terminal) work station to limit eye
▸ evaluate metabolic demands of a
job in a hot environment.
▸ Prevent musculoskeletal disorders, eg:
▸ evaluate lifting tasks, to determine strain
levels and redesign job if needed;
▸ evaluate work station layout to determine
potential for cumulative trauma disorder;
▸ evaluate repetitive manual operations to
reduce risk for cumulative trauma
What are ergonomic deficiencies?
▸ Extreme Posture
▸ Excessive Force
▸ Concentration of stress
▸ Static Loading
▸ Awkward lifting, pushing, pulling, carrying
▸ Vibration to the hand/arms or whole body.
▸ Repetitive tasks
▸ Physical exertion and temperature
Ergonomic evaluations
▸ Inspection of injury/illness reports for back injuries, muscle pains, cumulative trauma disorders.
▸ Evaluation of incidence of potentially ergonomically-related disorders to particular departments or jobs.
▸ Evaluate potential ‘problem jobs’ for ergonomic deficiencies:
▸ extreme reach
▸ excessive force
▸ static posture
▸ stress concentration
▸ faulty machine interface
▸ Prepare adequate training that explains why
ergonomic design is needed, so worker can apply knowledge rather than follow simple rules that may not be applicable in all situations.
What is Human Factors engineering?
Sub disciplines of ergonomics

A field that is concerned with information processing aspects of work. Intent is to design procedures, equipment and work environments to minimize likelihood of accident due to human error.

Human Factors research pays a great deal of
attention to design of labels, signs, controls,
displays, etc.

Focus on readability and minimizing errors.

Static work
when a muscle or muscle group remains contracted for an extended period of time.
Biomechanics is the sub discipline of ergonomics concerned with the mechanical properties of the human body.
▸ Low Back Pain:
▸ one of the most common causes of lost time
▸ most commonly associated with manual
NIOSH Lifting Equation
▸ Look at how load is moved:
▸ Horizontal position of hands from center of
▸ vertical position of hands from floor,
▸ travel distance,
▸ angular displacement,
▸ frequency factor,
▸ coupling accounts for
What types of problems does Human Factors engineering correct?
A field concerned with looking at
▸ Failures to perceive or recognize a hazardous
condition or situation
▸ Failures in the information processing or
decision-making processes
▸ Failures in motor actions following correct