February 12, 2003

What is Ergonomy

Ergonomics is the application of scientific information concerning human physiology to the design of objects, systems and environments for human use. Ergonomics applies to everything that involves people. Work systems, sports and leisure, health and safety should all embody ergonomic principles if they are well designed. Well applied ergonomic principles ensure that humans can work safely without the risk of injury.

The term Ergonomy is derived from the two Greek words: Ergon, meaning work and nomoi, meaning natural laws.

Why use Ergonomy

As early as 18th century, health personnel observed that workers whose jobs required them to maintain certain body positions for lengthy periods of time developed musculoskeletal problems. In the 20th century researchers have established the connection between certain job tasks and repetitive stress injuries, or RSIs.

How to incorporate Ergonomy

Ergonomy uses elements not only from physiological aspects of life but also from anatomy, psychology and design. Ergonomic products are proved to be environmentally friendly, comfortable, safe and efficient to use. With the help of the following basic ergonomic principles we are able to define postures which are less static and reduce the pressures acting on the body:

1. Work activities must allow people to adopt healthy and safe postures;
2. Muscular force should be exerted by the largest and strongest muscle group(s) available;
3. Work should be performed with the joints at about mid-point of their range of movement especially to the head, trunk and upper limbs.
(adapted from:

Below are a number of ways in which you can apply ergonomic principles to your own work or study area:


Adjusting your chair

1. Adjust the height of your seat so that your elbows are at the level of the keyboard (90 degrees).
2. Make sure that wrists are straight (180 degrees) and at the same level as the elbows.
3. Make sure that the angle of your knees is 90 degrees and that your feet are resting completely on the ground.

Adjusting the backrest:

4. Adjust the angle of the backrest so that your back is as straight as possible (90-110 degrees).
5. Adjust the height of the back rest so that your back is supported from the lower part up to the shoulder blades.


1. The top of your glass screen should be at the same level as your eyes.
2. If you wear bifocal lenses, lower the screen.
3. The screen should be about one arm’s length away.
4. Reduce the angle on your screen in order to avoid reflections.


1. The keyboard should be located between you and the screen.
2. The distance from the keyboard should be such that your elbows remain near your body.
3. Lower the supports at the back of the keyboard to reduce its angle.
4. The use of a retractable keyboard support should not interfere with the space left for the legs and should not cause the keyboard to be too low.


1. The mouse can be on the left or the right of the keyboard, depending on the user.
2. Remember that mouse buttons can be reprogrammed for left-handed people.
3. Set the mouse as close as possible to the keyboard.

Poor ergonomics can lead to undue stress on the body, which may lead to repetitive strain injuries. The first sign of these injuries is stiffness and discomfort in the affected body parts. Following is a list of common complaints associated with poor ergonomics, and some suggestions for reducing the discomfort.

Physical Health Issues Related to Poor Ergonomics

Diagnostic table of discomfort related to work stations.

Ergo products and Accessories

In a continuing quest to make computing more comfortable and healthy, companies have come up with an incredible variety of unexpected products and accessories. From wrist rests to glare screens, from footrests to foot-operated mice, from one-handed keyboards to ergonomic chairs.

Studies And Results

Over the last five years a study on the relationship between ergonomic office environments and productivity has been underway. The sample group includes managerial, technical, and clerical workers from a broad cross-section of North American industry. In the sample group approximately 4 per cent of managerial workers and approximately 60 per cent of clerical workers have direct work-station access to a computer terminal. The total study population is approximately 4,000 persons.


In the survey, workers using computer equipment, specifically video display equipment, more than one hour per day reported twice as many complaints of neck and shoulder discomfort as coworkers who did not use this equipment.

The workers also had higher rates of absenteeism, reported less job satisfaction and, at entry-level positions, had a higher turnover rate (approaching 30 per cent a year) than their co-workers.

A major incentive to purchase ergonomic equipment and to design ergonomic environments is the improved performance and well-being of office workers.

Office automation (OA) has been associated with increased absenteeism, reports of muscular discomfort, eyestrain, and reductions in job satisfaction.

However, through the use of ergonomic principles, people report a decrease in the risks of RSI’s (Repetitive stress injuries).

Information for the preceding article has been adapted from the following websites: