Ergonomics: the science of designing
the job, equipment, and workplace to fit the worker.
is the science of designing the job,
equipment, and workplace to fit the worker. Proper ergonomic design
is necessary to prevent repetitive strain injuries, which can
develop over time and can lead to long-term disability.
The International Ergonomics Association defines ergonomics as
Ergonomics (or human factors) is the scientific
discipline concerned with the understanding of interactions among
humans and other elements of a system, and the profession that
applies theory, principles, data and methods to design in order to
optimize human well-being and overall system
Ergonomics is employed to fulfill the two goals of health and
productivity. It is relevant in the design of such things as safe
furniture and easy-to-use interfaces to machines.
Ergonomics is concerned with the ‘fit’ between people and their
work. It takes account of the worker's capabilities and limitations
in seeking to ensure that tasks, equipment, information and the
environment suit each worker.
To assess the fit between a person and his work, ergonomists
consider the job being done and the demands on the worker; the
equipment used (its size, shape, and how appropriate it is for the
task), and the information used (how it is presented, accessed, and
changed). Ergonomics draws on many disciplines in its study of
humans and their environments, including anthropometry
, mechanical engineering
, industrial engineering
, industrial design
Typically, an ergonomist will have a BA or BS in Psychology,
Industrial/Mechanical Engineering or Health Sciences, and usually
an MA, MS or PhD in a related discipline. Many universities offer
Master of Science degrees in Ergonomics, while some offer Master of
Ergonomics or Master of Human Factors degrees. In the 2000s,
been moving into the field of ergonomics and the field has been
heralded as one of the top ten emerging practice areas.
(IEA) divides ergonomics broadly into
- Physical ergonomics: is concerned with human anatomical, and
some of the anthropometric, physiological and biomechanical
characteristics as they relate to physical activity. (Relevant
topics include working postures, materials handling, repetitive
movements, work related musculoskeletal disorders, workplace
layout, safety and health.)
- 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. (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 design.)
- Organizational ergonomics: is concerned with the optimization
of socio technical systems, including their organizational
structures, policies, and processes.(Relevant topics include
communication, crew resource management, work design, design of
working times, teamwork, participatory design, community
ergonomics, cooperative work, new work programs, virtual
organizations, telework, and quality management.
History and etimology
The foundations of the science of ergonomics appear to have been
laid within the context of the culture of Ancient Greece
. A good deal of evidence
indicates that Hellenic civilization in the 5th century BC used
ergonomic principles in the design of their tools, jobs, and
workplaces. One outstanding example of this can be found in the
description Hippocrates gave of how a surgeon's workplace should be
designed and how the tools he uses should be arranged (see
Marmaras, Poulakakis and Papakostopoulos, 1999) . It is also true
that archaeological records of the early Egyptians Dynasties made
tools, household equipment, among others that illustrated ergonomic
principles. It is therefore questionable whether the claim by
Marmaras, et al., regarding the origin of ergonomics, can be
justified (I G Okorji, 2009).
The term ergonomics
is derived from the Greek words
[work] and nomos
[natural laws] and first
entered the modern lexicon when Wojciech Jastrzębowski
word in his 1857 article Rys ergonomji czyli nauki o pracy,
opartej na prawdach poczerpniętych z Nauki Przyrody
Outline of Ergonomics, i.e. Science of Work, Based on the Truths
Taken from the Natural Science).
Later, in the 19th century, Frederick Winslow Taylor
the "Scientific Management
method, which proposed a way to find the optimum method for
carrying out a given task. Taylor found that he could, for example,
triple the amount of coal that workers were shoveling by
incrementally reducing the size and weight of coal shovels until
the fastest shoveling rate was reached. Frank
and Lillian Gilbreth
methods in the early 1900s to develop "Time and Motion Studies".
They aimed to improve efficiency by eliminating unnecessary steps
and actions. By applying this approach, the Gilbreths reduced the
number of motions in bricklaying
to 4.5, allowing bricklayers to increase their productivity from
120 to 350 bricks per hour.
World War II
marked the development of
new and complex machines and weaponry, and these made new demands
on operators' cognition. The decision-making, attention,
situational awareness and hand-eye coordination of the machine's
operator became key in the success or failure of a task. It was
observed that fully functional aircraft, flown by the best-trained
pilots, still crashed. In 1943, Alphonse Chapanis
, a lieutenant in the
U.S. Army, showed that this so-called "pilot error" could be
greatly reduced when more logical and differentiable controls
replaced confusing designs in airplane cockpits.
In the decades since the war, ergonomics has continued to flourish
and diversify. The Space Age
human factors issues such as weightlessness and extreme g-forces
. How far could environments in space be
tolerated, and what effects would they have on the mind and body?
The dawn of the Information Age
resulted in the new ergonomics field of human-computer interaction
Likewise, the growing demand for and competition among consumer goods
has resulted in more companies
including human factors in product design.
At home, work, or play new problems and questions must be resolved
constantly. People come in all different shapes and sizes, and with
different capabilities and limitations in strength, speed,
judgment, and skills. All of these factors need to be considered in
the design function. To solve design problems, physiology and
psychology must be included with an engineering approach.
than twenty technical subgroups within the Human Factors and
Ergonomics Society (HFES) indicate the range of applications for
ergonomics. Human factors engineering continues to be successfully
applied in the fields of aerospace
health care, IT
design, transportation, training, nuclear and virtual environments,
among others. Kim Vicente, a University of Toronto
Professor of Ergonomics, argues that the nuclear disaster
in Chernobyl is attributable to plant designers not paying
enough attention to human factors.
"The operators were
trained but the complexity of the reactor and the control panels
nevertheless outstripped their ability to grasp what they were
seeing [during the prelude to the disaster]."
Physical ergonomics is important in the medical field, particularly
to those diagnosed with physiological ailments or disorders such as
(both chronic and temporary) or
carpal tunnel syndrome
Pressure that is insignificant or imperceptible to those unaffected
by these disorders may be very painful, or render a device
unusable, for those who are. Many ergonomically designed products
are also used or recommended to treat or prevent such disorders,
and to treat pressure-related chronic
Human factors issues arise in simple systems and consumer products
as well. Some examples include cellular telephones and other
handheld devices that continue to shrink yet grow more complex (a
phenomenon referred to as "creeping featurism"), millions of VCRs
blinking "12:00" across the world because very few people can
figure out how to program them, or alarm clocks that allow sleepy
users to inadvertently turn off the alarm when they mean to hit
'snooze'. A user-centered
(UCD), also known as a systems approach or the usability engineering
to improve the user-system.
Design of ergonomics experiments
There is a specific series of steps that should be used in order to
properly design an ergonomics experiment. First, one should select
a problem that has practical impact. The problem should support or
test a current theory. The user should select one or a few
dependent variable(s) which usually measures safety, health, and/or
physiological performance. Independent variable(s) should also be
chosen at different levels. Normally, this involves paid
participants, the existing environment, equipment, and/or software.
When testing the users, one should give careful instructions
describing the method or task and then get voluntary consent. The
user should recognize all the possible combinations and
interactions to notice the many differences that could occur.
Multiple observations and trials should be conducted and compared
to maximize the best results. Once completed, redesigning within
and between subjects should be done to vary the data. It is often
that permission is needed from the Institutional Review Board
before an experiment can be done. A mathematical model should be
used so that the data will be clear once the experiment is
The experiment starts with a pilot test. Make sure in advance that
the subjects understand the test, the equipment works, and that the
test is able to be finished within the given time. When the
experiment actually begins, the subjects should be paid for their
work. All times and other measurements should be carefully measured
and recorded. Once all the data is compiled, it should be analyzed,
reduced, and formatted in the right way. A report explaining the
experiment should be written. It should often display statistics
including an ANOVA table, plots, and means of central tendency. A
final paper should be written and edited after numerous drafts to
ensure an adequate report is the final product.
Ergonomics in the workplace
Fundamentals for the Flexible
Workplace Variability and compatibility with desk components, that
flex from individual work activities to team settings.
Workstations provide supportive ergonomics for task-intensive
Outside of the discipline itself, the term 'ergonomics' is
generally used to refer to physical ergonomics as it relates to the
workplace (as in for example ergonomic chairs and keyboards
). Ergonomics in the workplace
has to do largely with the safety of employees, both long and
short-term. Ergonomics can help reduce costs by improving safety.
This would decrease the money paid out in workers’ compensation.
For example, over five million workers sustain overextension
injuries per year. Through ergonomics, workplaces can be designed
so that workers do not have to overextend themselves and the
manufacturing industry could save billions in workers’
Workplaces may either take the reactive or proactive approach when
applying ergonomics practices. Reactive ergonomics is when
something needs to be fixed, and corrective action is taken.
Proactive ergonomics is the process of seeking areas that could be
improved and fixing the issues before they become a large problem.
Problems may be fixed through equipment design, task design, or
environmental design. Equipment design changes the actual, physical
devices used by people. Task design changes what people do with the
equipment. Environmental design changes the environment in which
people work, but not the physical equipment they use.
Fields of ergonomics
is an interdisciplinary part of
ergonomics and studies the relationships of people to machines,
with the intent of improving such relationships. This may involve
redesigning equipment, changing the way people use machines, or
changing the location in which the work takes place. Often, the
work of an engineering psychologist is described as making the
relationship more "user-friendly."
Engineering psychology is an applied field of psychology
concerned with psychological factors
in the design and use of equipment. Human
is broader than engineering psychology, which is
focused specifically on designing systems that accommodate the
information-processing capabilities of the brain.
Macroergonomics is an approach to ergonomics that emphasizes a
broad system view of design, examining organizational environments,
culture, history, and work goals. It deals with the physical design
of tools and the environment. It is the study of the
society/technology interface and their consequences for
relationships, processes, and institutions. It also deals with the
optimization of the designs of organizational and work systems
through the consideration of personnel, technological, and
environmental variables and their interactions. The goal of
macroergonomics is a completely efficient work system at both the
macro- and micro-ergonomic level which results in improved
productivity, and employee satisfaction, health, safety, and
commitment. It analyzes the whole system, finds how each element
should be placed in the system, and considers all aspects for a
fully efficient system. A misplaced element in the system can lead
to total failure.
Macroergonomics, also known as organizational design and management
factors, deals with the overall design of work systems. This domain
did not begin to receive recognition as a sub-discipline of
ergonomics until the beginning of the 1980s. The idea and current
perspective of the discipline was the work of the U.S. Human
Factors Society Select Committee on the Future of Human Factors,
1980-2000. This committee was formed to analyze trends in all
aspects of life and to look at how they would impact ergonomics
over the following 20 years. The developments they found include:
- Breakthroughs in technology that would change the nature of
work, such as the desktop computer,
- The need for organizations to adapt to the expectations and
needs of this more mature workforce,
- Differences between the post-World War II generation and the
older generation regarding their expectations the nature of the new
- The inability of solely microergonomics to achieve reductions
in lost-time accidents and injuries and increases in
- Increasing workplace liability litigation based on safety
These predictions have become and continue to become reality. The
macroergonomic intervention in the workplace has been particularly
effective in establishing a work culture that promotes and sustains
performance and safety improvements.
- Cognitive Walk-through Method: This method is a usability
inspection method in which the evaluators can apply user
perspective to task scenarios to identify design problems. As
applied to macroergonomics, evaluators are able to analyze the
usability of work system designs to identify how well a work system
is organized and how well the workflow is integrated.
- Kansei Method: This is a method that transforms consumer’s
responses to new products into design specifications. As applied to
macroergonomics, this method can translate employee’s responses to
changes to a work system into design specifications.
- High Integration of Technology, Organization, and People
(HITOP): This is a manual procedure done step-by-step to apply
technological change to the workplace. It allows managers to be
more aware of the human and organizational aspects of their
technology plans, allowing them to efficiently integrate technology
in these contexts.
- Top Modeler: This model helps manufacturing companies identify
the organizational changes needed when new technologies are being
considered for their process.
- Computer-integrated Manufacturing, Organization, and People
System Design (CIMOP): This model allows for evaluating
computer-integrated manufacturing, organization, and people system
design based on knowledge of the system.
- Anthropotechnology: This method considers analysis and design
modification of systems for the efficient transfer of technology
from one culture to another.
- Systems Analysis Tool (SAT): This is a method to conduct
systematic trade-off evaluations of work-system intervention
- Macroergonomic Analysis of Structure (MAS): This method
analyzes the structure of work systems according to their
compatibility with unique sociotechnical aspects.
- Macroergonomic Analysis and Design (MEAD): This method assesses
work-system processes by using a ten-step process.
The best way to reduce pressure in the back is to be in a standing
position. However, there are times when you need to sit. When
sitting, the main part of the body weight is transferred to the
seat. Some weight is also transferred to the floor, back rest, and
armrests. Where the weight is transferred is the key to a good seat
design. When the proper areas are not supported, sitting in a seat
all day can put unwanted pressure on the back causing pain.
The lumbar (bottom five vertebrate in the spine) needs to be
supported to decrease disc pressure. Providing both a seat back
that inclines backwards and has a lumbar support is critical to
prevent excessive low back pressures. The combination which
minimizes pressure on the lower back is having a backrest
inclination of 120 degrees and a lumbar support of 5 cm. The
120 degrees inclination means the angle between the seat and the
backrest should be 120 degrees. The lumbar support of 5 cm
means the chair backrest supports the lumbar by sticking out
5 cm in the lower back area. One drawback to creating an open
body angle by moving the backrest backwards, is that it takes ones
body away from the tasking position, which typically involves
leaning inward towards a desk or table. One solution to this
problem can be founds in the kneeling
. A proper kneeling chair creates the open body angle by
lowering the angle of the lower body, keeping the spine in
alignment and the sitter properly positioned to task. The benefit
of this position is that if one leans inward, the body angle
remains 90 degrees or wider. One mis-perception regarding kneeling
chairs is that the body's weight bears on the knees, and thus users
with poor knees cannot use the chair. This misperception has led to
a generation of kneeling chairs that attempt to correct this by
providing a horizontal seating surface with an ancillary knee pad.
This design wholly defeats the purpose of the chair. In a proper
kneeling chair, some of the weight bears on the shins, not the
knees, but the primary function of the shin rests (knee rests) are
to keep one from falling forward out of the chair. Most of the
weight remains on the buttocks. Another way to keep the body from
falling forward is with a saddle seat. This type of seat is
generally seen in some sit stand stools, which seek to emulate the
riding or saddle position of a horseback rider, the first "job"
involving extended periods of sitting.
Another key to reducing lumbar disc pressure is the use of
armrests. They help by putting the force of your body not entirely
on the seat and back rest, but putting some of this pressure on the
armrests. Armrest needs to be adjustable in height to assure
shoulders are not overstressed.
The International Ergonomics Association 
(IEA) is a
federation of ergonomics and human factors societies from around
the world. The mission of the IEA is to elaborate and advance
ergonomics science and practice, and to improve the quality of life
by expanding its scope of application and contribution to society.
As of September 2008, the International Ergonomics Association has
46 federated societies and 2 affiliated societies.
The International Society of Automotive
(SAE) is a professional organization for mobility
engineering professionals in the aerospace, automotive, and
commercial vehicle industries. The Society is a standards
development organization for the engineering of powered vehicles of
all kinds, including cars, trucks, boats, aircraft, and others. The
Society of Automotive Engineers has established a number of
standards used in the automotive industry and elsewhere. It
encourages the design of vehicles in accordance with established
Human Factors principles. It is one the most influential
organizations with respect to Ergonomics work in Automotive Design.
This society regularly holds conferences which address topics
spanning all aspects of Human Factors/Ergonomics.
UK the professional body for ergonomists is the
Ergonomics Society and in the USA
it is the Human Factors and Ergonomics Society .
professional certification is managed by the Centre for
Registration of European Ergonomists 
(CREE). In the
USA the Board of Certification in Professional Ergonomics 
- Related subjects
- Related fields
- Related scientists
- Berkeley Lab. Integrated Safety Management: Ergonomics.
Website. Retrieved 9 July 2008.
- International Ergonomics Association. What is Ergonomics. Website. Retrieved 21
- Top 10 Emerging Practice Areas To Watch in the New
Millenium, article on American Occupational Therapy Association
- Marmaras, N., Poulakakis, G. and Papakostopoulos, V.
(1999). Ergonomic design in ancient Greece. Applied Ergonomics, 30
(4), pp. 361-368.
- Berkeley lab. Today at Berkeley lab: Ergonomic Tips for Computer
Users. Retrieved 8 January 2009.
- Technical Groups page at HFES Web site
- Unicor.gov. XXI Notes System Furniture. Retrieved 9 July
- Wickens and Hollands (200). Engineering Psychology and
- Brookhuis, K., Hedge, A., Hendrick, H., Salas, E., and Stanton,
N. (2005). Handbook of Human Factors and Ergonomics Models.
Florida: CRC Press.
- Jan Dul and Bernard Weerdmeester, Ergonomics for
Beginners - - A classic introduction on ergonomics - Original
title: Vademecum Ergonomie (Dutch) -published and updated since
- Stephen Pheasant, Bodyspace - - A classic exploration
- Kim Vicente, The Human Factor Full of examples and
statistics illustrating the gap between existing technology and the
human mind, with suggestions to narrow it
- Donald Norman, The Design of Everyday Things - - An
entertaining user-centered critique of nearly every gadget out
there (at the time it was published)
- Liu, Y (2007). IOE 333. Course pack. Industrial and Operations
Engineering 333 (Introduction to Ergonomics), University of
Michigan, Ann Arbor, MI. Winter 2007
- Wilson & Corlett, Evaluation of Human Work A
practical ergonomics methodology. Warning: very technical and not a
suitable 'intro' to ergonomics
- Wickens and Hollands (200). Engineering Psychology and
Human Performance. Discusses memory, attention, decision
making, stress and human error, among other topics
- Alvin R. Tilley & Henry Dreyfuss Associates (1993, 2002),
The Measure of Man & Woman: Human Factors in Design A
human factors design manual.
- Valerie J Gawron (2000), Human Performance Measures
Handbook Lawrence Erlbaum Associates - A useful summary of
human performance measures.
- Peter Opsvik (2009), "Re-Thinking Sitting" Interesting insights
on the history of the chair and how we sit from an ergonomic
- Thomas J. Armstrong (2008), Chapter 10: Allowances,
Localized Fatigue, Musculoskeletal Disorders, and Biomechanics
(not yet published)
- Peer-reviewed Publications
- (numbers between brackets are the ISI impact factor 2001-2003)
- Ergonomics (0.747)
- Applied Ergonomics (0.738)
- Human Factors (0.723)
- International Journal of Industrial Ergonomics
- Human Factors and Ergonomics in Manufacturing
- Travail Humain (0.260)
- Theoretical Issues in Ergonomics Science (-)
- International Journal of Occupational Safety and