Human Factors Psychology

Human factors psychology is a branch of experimental psychology often associated with industrial/organizational psychology because it concentrates on the interaction of people and machines. Good human factors engineering can make a product convenient and easy to use, rather than frustrating and confusing.

What is Human Factors psychology?

Human Factors as a discipline was stimulated by pilot errors that cost many lives during World War II. Analysis of flying accidents revealed that many were due to the confusing layout of instruments in airplane cockpits. Pilots were faced with a bewildering array of dials and gauges in the cockpit, yet they were expected to keep track of all pertinent information and respond appropriately in emergencies. Human Factors psychologists helped to identify problems in cockpit design. They attempted to design instrument panels that were clear and easy to use for humans.

How are Human Factors considerations relevant to manufacturers?

Similarly, the designs of consumer products such as cameras and DVD players require that human factors be taken into account. Kitchen appliances, office furniture, and many other products benefit from thoughtful study of object/human interactions. Good design can help the sales of any manufactured product, while poor design can kill repeat sales and doom a product.

Many amusing examples of bad design are found at Michael J. Darnell's web site, www.baddesigns.com. Visitors to the site are invited to submit examples of bad product design. In each case, a product would be more convenient if the designer had taken into account the possibility or confusion or misunderstanding or inconvenience on the part of the customer. For example, consider the "ergonomic toothbrush." A correspondent wrote to the web site about it:

What was wrong with the "ergonomic toothbrush"?


"Ergonomic" toothbrushes described on <http://www.baddesigns.com>

This toothbrush comes in both right-handed and left-handed versions. It is contoured to fit the hand and has a depression for the thumb. The idea is that since you probably hold your toothbrush with the preferred hand, why not contour it to make it comfortable to hold?

The problem with using this toothbrush is in holding it only one way. Ordinarily, people will re-position the toothbrush in their hand as they change from brushing one side of their mouth to the other, or in order to reach all the surfaces of their teeth. The user of this toothbrush faces a dilemma: do I rotate my grip on the handle and go against how the handle is shaped? For example, if the right-handed toothbrush is held as intended, it is difficult to brush the right side of the mouth. The wrist must be held at an awkward angle. If the handle is rotated in the hand, it no longer conforms to the contour of hand." ("Ergonomic toothbrush?", May 10, 1999)

What is ergonomics?

The label "ergonomic toothbrush" is ironic, because ergonomics is the study of the efficiency and safety of human-machine systems. If this company had actually hired a human factors expert to test the ergonomics of their product, they would have found out that the toothbrush was not well designed.


Write to Dr. Dewey at psywww@gmail.com.

Don't see what you need? Psych Web has over 1,000 pages, so it may be elsewhere on the site. Do a site-specific Google search using the box below.

Custom Search

Copyright © 2007 Russ Dewey