HUMAN FACTORS ENGINEERING
SYED WAQAS KHAN
11 IN 96
"The field of human factors engineering uses scientific knowledge about human
behavior in specifying the design and use of a human-machine system. The aim is to
improve system efficiency by minimizing human error."
"The field of industrial ergonomics is devoted to the alleviation of the rigors of the
workplace and to the improvement of the persons performance on the job."
"Industrial ergonomics is the application of those sciences relating human
performance (physiology, psychology, and industrial engineering) to the improvement
of the work system, consisting of the person, the job, the tools and equipment, the
workplace and work space, and the immediate environment."
Adams, J. A. (1989)
Human Factors Engineering:
"...human engineering is not synonymous with human factors. The term 'human factors‘
is more comprehensive, covering all biomedical and psychosocial considerations
applying to man in the system. It includes not only human engineering, but also life
support, personnel selection and training, training equipment, job performance aids,
and performance measurement and evaluation
Alexander, D. C. (1986)
Air Force Systems Command USA (1977)
Human Factors and Human Engineering:
“knowledge based on scientific studies of ordinary people in work
situations...applied to the design of processes and machines, to the layout
of work places, to methods of work, and to the control of the physical
environment, in order to achieve greater efficiency of both men and
"The study of human capability and psychology in relation to the
working environment and the equipment operated by the worker."
Applied Ergonomics Handbook (1974)
Parker, S. P. (1989)
The primary purpose of human factors engineering is to provide designers,
particularly those with limited background in psychology, with some knowledge of
how people sense, process information, and respond; as well as to introduce
data, principles, and methods that are useful in eliciting an acceptable level of
human performance in systems."
The main goals in human factors engineering are to :-
(1) Consider any man/machine combination as a total system to insure that the
equipment operational requirements do not exceed human abilities.
(2) Consider the human performance tolerance, thereby insuring optimal speed,
accuracy, and quality of performance; eliminating hazards to operating
personnel; and maximizing the comfort of the operator.
WHY Human Factors Engineering ????
In our changing, fast paced society, people are under more stress than ever.
To help relieve tension, stress and to correct posture for better health,
ergonomists takes in to consideration important key factors.
These key factors would include how a person would be sitting, standing or
moving about in an area.
This would also include the length of time for these activities. Range of motion
and how humans normally move are taken into consideration.
Ergonomists want to find out what makes certain situations more stressful on the
body and how they can relieve stress.
For example, many people who work in offices spend up to eight hours a day
sitting in a chair and staring at a screen, moving their hands about a
keyboard or mouse. While being in a sitting position in a certain form would
be considered comfortable, humans generally slump over after a certain
period of time in the same position. To prevent this, ergonomics may
recommend moving about into different, posture perfect positions in order to
keep you comfortable and relieve the body of stress and tension.
Why is Ergonomics important?
When you put together the education of ergonomics and design it to practical
applications in every day use, you’ll find a more comfortable work environment.
This begins with the understanding of how the body works, what makes the
body most comfortable and techniques and timing.
The studies that are put together test and retest certain products and daily
The recommended suggestions may change as studies progress.
For example, it was conventional to put a computer monitor as close as 18
inches from the face. Now it is suggested that a monitor should be as far away as
possible as long as you are still able to read it easily. These changes could only
occur with the continued study and efforts with ergonomists
What are the results of
In addition to making your every day life better, you also can perform better in the
workplace with some applied techniques that we learn from ergonomics.
A lot of the focus for comfort in the workplace comes from the position of the
keyboard and mouse. With technology, we need to retrain ourselves to adjust our
hands and wrists.
The improper use of the keyboard and the wrong positioning of the wrists for long
periods of time could cause carpal tunnel syndrome.
The proper positioning of the keyboard has been debated with ergonomists.
They do all agree that the wrists should be level at all times, with frequent rest
stops for flexing the muscles
It is suggested that the elbow should be slightly lower than where the wrists are.
Now, special mats, keyboards and other products help with the support of the
wrists and arms in addition to the education of the techniques
The Application Of Ergonomics In The
Even daily activities can be considered detrimental to people.
Would you imagine that talking on the phone for long periods of time damaging to your
posture and creates tension?
In reality, when most people use a traditional telephone, they slump one shoulder, bending it
into the ear they are listening to.
This eventually makes the body uncomfortable, even when you switch listening ears
In this case, it is recommended that anyone who uses the telephone for long periods of time
invest in a head set for their telephone.
You could also use a speakerphone. Either product would relieve stress on the shoulder and
Another case would be sitting for long periods of time. This puts strain on your back, your
buttocks and even your legs. Some sitting positions can even cut off circulation to your legs
and feet, which is unhealthy. Possible solutions would be to actually move at frequent intervals.
If you are forced to sit, a readjusting chair that lets you move and stretch periodically will help.
If you can, get up and stretch, or try doing work or other things while standing up and moving
Applying Ergonomics To Every Day Life
The most common industrial injuries include back strain, slip and fall injuries, and
repetitive stress injuries in the arms and wrists. All of these are easily prevented
with simple ergonomic interventions.
By implementing industrial ergonomics, businesses reap several benefits:
•Fewer injuries on the job
•Reduced cost for disability and company insurance
•Less time missed by employees due to injury
•Higher productivity rates
The Role of Ergonomics in the Industrial Workplace
Industrial workplaces present unique challenges because they often
incorporate assembly lines, shared workstations, and heavy loads. Since these
conditions are largely inherent to the industrial workplace, it is important for
businesses to use proper precautions to protect their employees from workplace
To prevent slip and fall accidents, anti-fatigue mats provide extra traction.
They also pad the floor, preventing leg and back fatigue for employees who
stand for long periods. If the edges of anti-fatigue mats present a tripping
hazard, employees can strap ErgoMates to their shoes, for extra traction
wherever they go.
Ergonomic Footrests further relieve strain on the legs and feet. Employees
who stand for long periods can alternate their weight, resting the muscles in
each leg. Heavy-duty models are designed specifically for industrial workplaces,
so they can be adjusted to multiple heights for different workers.
Basic Guidelines for Industrial Ergonomics
If possible, employees should be able to switch between sitting and standing. The
added height of teller stools generally makes these stools an excellent option for
standing workstations that are common in industrial settings.
Because many industrial workplaces require employees to share workstations, it
is important that each employee be able to customize the height of the work
surface. Adjustable tables provide an easy means for each employee to
customize the workstation height.
Employees should learn and practice proper lifting habits. An expert can conduct
an in-house ergonomic workshop to demonstrate the best way to handle heavy
loads without incurring back injuries.
To supplement proper lifting habits, carts and hand trucks significantly reduce the
risk of back injuries caused by heavy lifting.
Workers can prevent injuries to the shoulders, elbows, wrists, and hands by using
forearm supports. Some adjustable models attach permanently to the table, while
foam wedge rests can easily be moved to any workstation
"'Anthropotechnics'...means and goals are similar to those of the American 'Human
Engineering'...Anthropotechnics is the scientific discipline dealing with the
interrelationship between man and machine and is aimed at the optimum of this
functional unit in terms of efficiency, reliability, and cost effectiveness through the
adaptation of the machine to man's capabilities and requirements."
Anthropometry is the scientific measurement and collection of data about
human physical characteristics and the application (engineering anthropometry) of
these data in the design and evaluation. of systems, equipment, manufactured
products, human environments, and facilities
The field of anthropometry encompasses a variety of human body measurements,
such as weight, height, and size; including skin fold thicknesses, circumferences,
lengths, and breadths.
Bernotat, R. K., & Gartner, K.-P. (1972)
Anthropotechnics and Human Engineering:
• Static Anthropometry
• Dynamic Anthropometry
External human body dimensional measurement taken when a man is placed
in a rigid static position i.e. standing, sitting, or other adopted postures.
The dimensional measurement of human body with various movements
taken into consideration in different adopted postures which the work
context demands are termed dynamic anthropometry.
Anthropometry is of two types
Human physical stature is a useful supplementary indicator of well-being. Height and
weight are components and a relatively easily measured indicator of biological
welfare. In addition, we gain hitherto unknown insights of the effect of economic
processes on the human organism.
Ergonomics actually started in the kitchen. Lillian Muller
Gilbert was an inventor, author, industrial engineer, industrial
psychologist, and mother of twelve children.
She patented many kitchen appliances including an electric
food mixer, shelves inside refrigerator doors, and the trash can
with foot-pedal lid-opener.
Gilbert is best known for her work with her husband on time
and motion studies.
But after her husband's death, Lillian was an industrial
engineer for General Electric, working on kitchen design
She interviewed over 4,000 women to design the proper
height for stoves, sinks, and other kitchen fixtures. Today much
of the advice in kitchen design is derived from her ideas
Interesting Fact About Kitchen And Ergonomics Relation:-
Schacter and Tulving (as cited in Driscoll, 2001) state that “a memory system is
defined in terms of its brain mechanisms, the kind of information it processes,
and the principles of its operation”
Information processing system / model (IPM)
The IPM consists of three main components; sensory memory, working
memory, and long-term memory (see Figure).
Sensory and working memory enable people to manage limited amounts of
incoming information during initial processing.
whereas long-term memory serves as a permanent repository for
In this entry, the information processing model will be used as a metaphor
for successful learning because it is well supported by research and provides a
well-articulated means for describing the main cognitive structures (i.e.,
memory systems) and processes (i.e., strategies) in the learning cycle
Information Processing System
It is concerned with human anatomical, anthropometric, physiological and
biomechanical characteristics as they related to physical activity.
Relevant topics may include working postures, material handling, repetitive
movements, work related musculoskeletal disorders, workplace layout, health and safety.
A proper fit of a product to a user does not end with physical interfaces.
Cognitive / perceptual 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 include mental workload, decision-making, skilled performance,
human-computer interaction, human reliability, work stress and training as these may
relate to human-system and Human computer interaction design.
Digital human modeling is being actively used in industries around the world to
reduce the need for physical prototypes and create better and safer designs faster
than was previously possible.
Contemporary human modeling software tools are actively assimilating a
variety of previously disconnected human modeling knowledge, including
population anthropometry descriptions and physical capability models.
The large amount of ergonomic and anthropometric knowledge integrated into
these solutions makes them efficient tools to answer a wide variety of human
factors questions of designs.
At the same time, the global nature of these tools is serving to consolidate and
expose research findings from around the world and steering academic research
direction and focusing the presentation of the results for model inclusion.
While there are many areas that can be explored using the current offering of
modeling solutions, many interesting challenges remain as we work to make
virtual humans as lifelike as technology and our knowledge of humans allow.
Unfortunately All my class mates
sit ergonomically wrong !!!!!
ANOTHER INTERESTING FACT