Human factors

Human factors (also known by its acronym, HF; alternatively known as human factors science; 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 INCOSE Systems Engineering Handbook (4th edition),

Human factors. The systematic application of relevant information about human abilities, characteristics, behavior, motivation, and performance. It includes principles and applications in the areas of human-related engineering, anthropometrics, ergonomics, job performance skills and aids, and human performance evaluation.

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.

According to the FAA AC 120-72,

Human factors. The scientific study of the interaction between people and machines.

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.

Dirty Dozen

Main wikipage: Dirty Dozen of Human Factors

The Dirty Dozen of Human Factors is the twelve most common maintenance-related human factors that are responsible for the majority of incidents and accidents in aviation.

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

Applications

In maintenance training

According to the FAA AMT Handbook,

The term human factors has grown increasingly popular as the commercial aviation industry realize that human error, rather than mechanical failure, underlies most aviation accidents and incidents. Human factors science or technologies are multidisciplinary fields incorporating contributions from psychology, engineering, industrial design, statistics, operations research, and anthropometry. It is a term that covers the science of understanding the properties of human capability, the application of this understanding to the design, development, and deployment of systems and services, and the art of ensuring successful application of human factor principles into the maintenance working environment.

The list of human factors that can affect aviation maintenance and work performance is broad. They encompass a wide range of challenges that influence people very differently as humans do not all have the same capabilities, strengths, weaknesses, or limitations. Unfortunately, aviation maintenance tasks that do not account for the vast amount of human limitations can result in technical error and injuries. Figure 14-4 shows some of the human factors that affect AMTs. Some are more serious than others but, in most cases, when you combine three or four of the factors, they create a problem that contributes to an accident or incident.

Elements of Human Factors Human factors are comprised of many disciplines. This section 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.

The study and application of human factors is complex because there is not just one simple answer to fix or change how people are affected by certain conditions or situations. Aviation maintenance human factors research has the overall goal to identify and optimize the factors that affect human performance in maintenance and inspection. The focus initiates on the technician but extends to the entire engineering and technical organization. Research is optimized by incorporating the many disciplines that affect human factors and help to understand how people can work more efficiently and maintain work performance.

By understanding each of the disciplines and applying them to different situations or human behaviors, we can correctly recognize potential human factors and address them before they develop into a problem or create a chain of problems that result in an accident or incident.

See also

• https://www.faa.gov/about/initiatives/maintenance_hf/videos/
• https://www.faa.gov/about/initiatives/maintenance_hf/training_tools/
• https://www.faa.gov/tv/?mediaId=450
• https://www.faa.gov/TV/?tag=human%20factors
• https://www.faa.gov/regulations_policies/handbooks_manuals/aircraft/media/amt_general_handbook.pdf

New batch

• https://www.faa.gov/TV/?tag=osa
• https://www.faa.gov/TV/?tag=Technical%20Operation
• https://www.faa.gov/TV/?mediaId=1149
• https://www.faa.gov/TV/?mediaId=1151
• https://www.faa.gov/TV/?mediaId=1152
• https://www.faa.gov/TV/?mediaId=1153
• https://www.faa.gov/TV/?mediaId=1150