Practitioners of ergonomics, ergonomists, contribute to the planning, design and evaluation of tasks, jobs, products, organisations, environments and systems in order to make them compatible with the needs, abilities, and limitations of people.

Derived from the Greek ergon (work) and nomos (laws) to denote the science of work, ergonomics is a systems-oriented discipline which now applies to all aspects of human activity. Practicing ergonomists must have a broad understanding of the full scope of the discipline, taking into account the physical, cognitive, social, organisational, environmental and other relevant factors. Ergonomists often work in particular economic sectors or application domains. These application domains are not mutually exclusive and they evolve constantly. New ones are created; old ones take on new perspectives.

Within the discipline, domains of specialisation represent deeper competencies in specific human attributes or characteristics of human interaction:

Physical ergonomics

Physical ergonomics is concerned with human anatomical, anthropometric, physiological and biomechanical characteristics as they relate to physical activity. The relevant topics include working postures, materials handling, repetitive movements, work-related musculoskeletal disorders, workplace layout, safety and health. Physical ergonomics is also concerned with how the physical environment around you might affect your performance.

‘Physical’ here means the kinds of things physicists know and love – heat, light, noise, dusts, chemicals, and so on. For example, there’s a thermal comfort range which suits people best – unless they are doing hard physical work, in which case they might prefer a cooler range. Similarly with noise; at night, you might want things quiet so that you can sleep; in a club, you might want it a bit louder! Physical ergonomics is about understanding the effects of these aspects of the environment on people, and in particular, the harmful effects. Then you can design environments for people which won’t harm them, and they might even enjoy the experience.

Cognitive ergonomics

Cognitive ergonomics is concerned with mental processes (‘brain work’), 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.

Take Air Traffic Control as an example; the Controller has a screen (or two) built into the workstation, plus telephones and radios. This all presents the controller with information, which has to be understood, digested, predictions of problems worked out, decisions made, and then the decisions have to be communicated and executed. Cognitive ergonomists would be looking at this process, and then trying to design the workstation, the whole system, the training, and the environment around the workstation to allow the process to happen swiftly and safely. For example, the ergonomist might do a lighting survey, to make sure the ceiling lights do not reflect off the screens, so that the controller can actually see what is on the screen (it’s difficult to make the right decision when you can’t read the information).

Cognitive ergonomists might also be interested in how long it is reasonable to expect controllers to work, so that they are off shift before the probability of them making a mistake begins to rise. They might also try to introduce more automation, to give the controller more time to think about the problem aircraft, without having to check on the ‘safe’ aircraft at the same time.

Organisational ergonomics

Organisational ergonomics is concerned with the optimisation of sociotechnical systems, including their organisational 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, organisational culture, virtual organisations, remote and mobile working, and quality management.

Organisational ergonomics is trying to organise people and the work to best effect. Staying with Air Traffic Control; the ergonomist might be trying to create a process that matches controllers to shifts; the aim here might be to ensure you don’t have the situation where all the controllers on the daytime shift at the peak of the holiday season have just left training school, and there’s nobody around with real experience of the problems. This process that the ergonomist has designed would be used both by Human Resource people and by managers, to help make sure that this scenario doesn’t happen.

Another example; in a steel rolling mill, the management has decided that they need to reduce the staff on each shift by 2 people. Can this be done safely, for all the likely operational scenarios in the mill (including the disaster scenarios)? How should the teams of operators be organised? In the new jobs that come out of this, what training will be necessary for each of the team members?

• Physical size and shape (anthropometry & biomechanics)
• Physical needs (physiology & biology)
• Body rhythms (chronobiology)
• Human input characteristics (physiology, sensory psychology, physics)
• Information and decisions (graphic design, psychology, information sciences)
• Human output characteristics (biomechanics, physiology, psychology, communication studies)
• Environmental tolerances (biology, psychology, forensics)
• Data capture and analysis (statistics, business methods, graphic design)
• Working practices & business processes (design, engineering, management, psychology)
• Organisational restructuring (organisational theory)
• Culture and motivation (psychology, sociology)
• Systems design (systems engineering principles, OR, AI, disaster studies)