Human factors

Human factors (also known by its acronym, HF; hereinafter, HF) is the scientific study of influence of human characteristics called factors on interactions between people and other entities that form one system, as well as those interactions themselves.

Trivia

Definitions

According to the International Ergonomics Association,

Ergonomics (human factors) is the scientific discipline concerned with the understanding of the 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.

Ergonomics vs HF

Two terms, HF and ergonomics, are often used interchangeably. Some view them as essentially synonymous.

However, ergonomics is more commonly applied to interactions between a human and non-human components of a system, while HF more frequently, though not always, refers to both human-to-human and human-to-non-human interactions.

Ergonomics emerged as a science of labor in the middle of the 1800s. More than a hundred years later, in the late 1900s, HF emerged as a science to reduce human errors.

History

Three trends contributed to HF as we now this scientific study today:

1. Ergonomics studies HF mostly as factors in physical and mental usability. However, ergonomics rarely concentrates on human errors.
2. Introduction of black boxes in aviation allowed for more detailed research on the causes of airplane crashes. Surprisingly to the researchers, a few of them happened not because of unusable technology or lack of crew technical skills, but because of poor team communication and situational unawareness. To mitigate human errors, the aviation industry developed the crew resource management (CRM) training in the 1980s. This training was designed for airplane crew only and the HF term was initially used to indicate the science behind this training. Later, it became clear that some of the crashes occurred not because of the crew performance, but because of poor maintenance. Separate training, maintenance resource management (MRM) was systematized and introduced in the 1990s.
3. Chernobyl disaster sparked concerns about safety culture and this term initially appeared in the report on this tragedy. It appears that the crew responsible for this disaster was trained on the related theories and the non-human systems worked as they were supposed to work, but the crew didn't take safety seriously.

Later, some other industries such as construction and cyber-security, as well as occupations such as information architects started contributing to HR studies as well.

Human-machine interactions

Main wikipage: Human-machine interaction

HF in systems engineering

Main wikipage: Human factors engineering

Traditional systems engineering rarely considers people such as a user, operator, mechanic, writer, designer, teacher, and/or everyone else who interfaces with a system as a part of this system. A special term, human factors engineering, is coined in order to address this gap.

In human factors engineering, HF involves not only the understanding of human factors, but mainly how those factors relate to the overall operation of the system.

System vs user

Trade-off.

User interface

Main wikipage: User interface

Elements of Human Factors

Human factors are comprised of many disciplines. In this section we will discusses ten of those disciplines: Clinical Psychology, Experimental Psychology, Anthropometrics, Computer Science, Cognitive Science, Safety Engineering,Medical Science, Organizational Psychology, Educational Psychology, and Industrial Engineering

Evolution of Maintenance Human Factors

With the onset of World War I (1914–1918), more sophisticated equipment was being developed and the inability of personnel to use such systems led to an increased interest in human capability. The war also brought on the need for aeromedical research and the need for testing and measurement methods. By the end of World War I, two aeronautical labs were established, one at Brooks Air Force Base, Texas, and the other at Wright Field outside of Dayton, Ohio. Another significant development was in the civilian sector, where the effects of illumination on worker productivity were examined. This led to the identification of the Hawthorne Effect. With the onset of World War II (1939–1945), it was becoming increasingly harder to match individuals to preexisting jobs. Now the design of equipment had to take into account human limitations and take advantage of human capabilities. This change took time as there was a lot of research to be done to determine the human capabilities and limitations that had to be accomplished. The scope of the research also broadened from small equipment to entire workstations and systems. In the civilian industry, the focus shifted from research to participation through advice to engineers in the design of equipment.

The Pearl Model

For more than a decade, the term “PEAR” has been used as a memory jogger, or mnemonic, to characterize human factors in aviation maintenance. PEAR prompts recall of the four important considerations for human factors programs, which are listed below.

• People who do the job.
• Environment in which they work
• Actions they perform.
• Resources necessary to complete the job.