Human factors engineering

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 performance (definition adopted by the International Ergonomics Association in 2000).

Ergonomists contribute to the design and evaluation of tasks, jobs, products, environments and systems in order to make them compatible with the needs, abilities and limitations of people (IEA, 2000).

Domains
The IEA divides ergonomics broadly into three domains:

Physical ergonomics deals with the human body's responses to physical and physiological loads. Relevant topics include manual materials handling, workstation layout, job demands, and risk factors such as repetition, vibration, force and awkward/static posture as they relate to musculoskeletal disorders (see repetitive strain injury).

Cognitive ergonomics, also known as engineering psychology, concerns mental processes such as perception, attention, cognition, motor control, and memory storage and retrieval as they affect interactions among humans and other elements of a system. Relevant topics include mental workload, vigilance, decision making, skilled performance, human error, human-computer interaction, and training.

Organizational ergonomics, or macroergonomics, is concerned with the optimization of sociotechnical systems, including their organizational structures, policies, and processes. Relevant topics include shift work, scheduling, job satisfaction, motivational theory, supervision, teamwork, telework and ethics.

History
Italian Bernardino Ramazinni (1633-1714) became the first physician to write about work-related injuries and illnesses in his 1700 publication, "De Morbis Artificum (Diseases of Workers)". Ramazinni was ostracized by his fellow doctors for visiting the workplaces of his patients in order to identify the causes of their disorders. The term ergonomics (from the Greek words ergon [work] and nomoi [natural laws]) first entered the modern lexicon when Wojciech Jastrzębowski used the word in his 1857 article Rys ergonomji czyli nauki o pracy, opartej na prawdach poczerpniętych z Nauki Przyrody (adapted from a previous version of this page).

Later in the 19th century, Frederick Winslow Taylor pioneered the "Scientific Management" method, an approach that sought the single best method to perform a job and its tasks. By incrementally reducing the size and weight of coal shovels until the optimum shoveling rate was reached, Taylor tripled the amount of coal that workers could shovel in a day. Frank and Lilian Gilbreth, in the early 1900s, expanded Taylor's methods to develop "Time and Motion Studies" that aimed to improve efficiency by eliminating unnecessary steps and actions. By applying this approach, the Gilbreths reduced the number of motions in bricklaying from 18 to 4.5, allowing bricklayers to increase their pace of laying bricks from 120 to 350 bricks per hour.

World War II marked the advent of highly sophisticated machines and weaponry, creating previously unseen cognitive demands on operators in terms of decision-making, attention, situational awareness and hand-eye coordination. It was observed that perfectly working aircraft, flown by the best-trained pilots, still crashed. In 1943, Alphonse Chapanis, a lieutenant in the U.S. Army, showed that "pilot error" could be greatly reduced when more logical and differentiable controls replaced confusing designs in airplane cockpits.

In the decades following the war and leading to today, ergonomics has continued to flourish and diversify. The Space Age created new human factors issues such as weightlessness and extreme G-forces. To what extent could these environments be tolerated and what effects would they have on the mind and body? The Information Age has spawned the field of human-computer interaction (HCI) while the growing demand for and competition among consumer goods and electronics has resulted in more companies heeding human factors in product design.

Foundations
Ergonomics draws on many disciplines in its study of humans and their environments, including anthropometry, biomechanics, engineering, kinesiology, physiology and psychology.

Typically, an ergonomist will have a BA or BS in Psychology, Industrial/Mechanical Engineering or Health Sciences, and usually a 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.

Applications
The more 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, aging, health care, IT, product 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]."

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 design (UCD), also known as a systems approach or the usability engineering lifecycle aims to improve the user-system fit.

Resources
Books Ergonomics for Beginners - Jan Dul and Bernard Weerdmeester - A classic introduction on ergonomics - Original title: Vademecum Ergonomie (Dutch) -published and updated since 1960's. Bodyspace - Stephen Pheasant - A classic exploration of ergonomics. The Human Factor - Kim Vicente - Full of examples and statistics illustrating the gap between existing technology and the human mind, with suggestions to narrow it. The Design of Everyday Things - Donald Norman - An entertaining user-centered critique of nearly every gadget out there (at the time it was published). Evaluation of Human Work - Wilson & Corlett - A practical ergonomics methodology. Warning: very technical and not a suitable 'intro' to ergonomics. Engineering Psychology and Human Performance - Wickens and Hollands - Discusses memory, attention, decision making, stress and human error, among other topics. The Measure of Man & Woman - Henry Dreyfuss Associates - A human factors design manual that has controversial elements.

Peer-Reviewed Publications (between brackets mean ISI impact factor 2001-2003)

Ergonomics (0.747) Applied Ergonomics (0.738) Human Factors (0.723) International Journal of Industrial Ergonomics (0.395) Human Factors and Ergonomics in Manufacturing (0.311) ''Travail Humain (0.260) Theoretical Issues in Ergonomics Science (-) International Journal of Occupational Safety and Ergonomics (-)

Organizations
 * IEA International Ergonomics Association
 * Board of Certification in Professional Ergonomics (BCPE) - Established in 1990 as an independent nonprofit organization, the BCPE is the certifying body for individuals whose education and experience indicate broad expertise in the practice of human factors/ergonomics.
 * ACE Association of Canadian Ergonomists
 * HFES Human Factors and Ergonomics Society - USA

Websites
 * Ergonomics research: Anthropometrics, ergonomic tools, product design, workplace ergonomics, injury data
 * More about ergonomics and its history; workplace safety; guidelines &amp; standards
 * Straight talk about ergonomics training at a non-commercial site.
 * Usernomics &mdash; Resources and consulting for user interface design and usability testing