According to the International Ergonomics Association, there are three broad domains of ergonomics: physical, cognitive, and organizational.
A. Physical Ergonomics
Physical ergonomics is concerned with human anatomical, anthropometric, physiological and biomechanical characteristics as they relate to physical activity. This is the ergonomics domain we are most concerned with in the workplace, and most of the content on this site is very much focused on workplace ergonomics.
Workplace Ergonomics
The science of fitting workplace conditions and job demands to the capabilities of the working population. Ergonomics is an approach or solution to deal with a number of problems—among them are work-related musculoskeletal disorders.
At its core, workplace ergonomics is really about building a better workplace. When jobs are designed to match the capabilities of people, it results in better work and a better experience for the person doing it. The ergonomic improvement process systematically identifies ergonomic hazards and puts in place engineering and administrative control measures to quantifiably reduce risk factors.
Unlike in earlier times when an engineer designed a whole machine or product, design is a team effort nowadays. The ergonomist usually has an important role to play both at the conceptual phase and in detailed design as well as in prototyping and the evaluation of existing products and facilities.
B. Cognitive Ergonomics
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. The 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.
C. Organizational Ergonomics
Organizational ergonomics is concerned with the optimization of sociotechnical systems, including their organizational structures, policies, and processes. The relevant topics include communication, crew resource management, work design, design of working times, teamwork, participatory design, community ergonomics, cooperative work, new work paradigms, virtual organizations, tele-work, and quality management.
This is achieved through two basic approaches
Biomechanical Approach:
Biomechanics relates the principles of physics to the human body to determine the mechanical stresses that affect it and the resultant muscular forces needed to counteract the stresses. Application of the biomechanical approach has generally been limited to the analysis of high force lifting, lowering, pushing and pulling tasks.
Epidemiological Approach:
Epidemiology studies groups of people and analyses information and data to determine the root causes of back injuries. A better understanding of what has happened in the past can be used to help prevent injuries in the future. Each of the approaches used in the design and analysis of material handling tasks is appropriate under different circumstances and conditions. These risk factors can be reduced through informed purchasing and workplace design, retrofit engineering controls, administrative controls, work practice definitions, or in some cases, personal protective equipment. Corporate initiatives designed to identify and control workplace ergonomic concerns have proven to be effective in reducing the incidence of MSDs and have been efficient investments producing measurable bottom-line benefits.