Systems Analysis and Synthesis

8.3. Human Factors

Human Factors or ergonomics may be divided into three broad categories:

Physiological:   factors associated with the way the human body is made.

Cognitive:   factors associated with the fixed wiring of the brain.

Behavioural:   factors associated with the brain’s ability to learn and adapt.

It isn’t always easy to decide to which category a given factor should belong.

8.3.1. Physiological Factors

If a person is to spend much time using a computer, it is important to provide a comfortable workstation.

• The seat should be high enough for the thighs to rest without cutting off circulation to the legs — usually about 50 cm above the floor.

• The keyboard should be at a height where the wrists are slightly below the elbows — usually about ...