Ergonomics of computing

Ergonomics is the study of the “fit” between people and their working environment. Because computers are such a significant part of the working life of so many people, finding ways for people to maximize efficiency and reduce health risks associated with computer use is increasingly important.

Since the user will be looking at the computer monitor for hours on end, it is important that the display be large enough to be comfortably readable and that there be enough contrast. Glare on the monitor surface should be avoided. It is recommended that the monitor be placed so that the top line of text is slightly below eye level. A distance of about 18 inches to two feet (roughly arm’s length) is recom-mended. There has been concern about the health effects of electromagnetic radiation generated by monitors. Most new monitors are designed to have lower emissions.

While the “standard” keyboard has changed little in 20 years of desktop computing, there have been attempts at innovation. One, the Dvorak keyboard, uses an alter-native arrangement of letters to the standard “QWERTY.” Although it is a more logical arrangement from the point of view of character frequency, studies have generally failed to show sufficient advantage that would compensate for the effort of retraining millions of typists. There have also been specially shaped “ergonomic” keyboards that attempt to bring the keys into a more natural relationship with the hand (see keyboard).

The use of a padded wrist rest remains controversial. While some experts believe it may reduce strain on the arm and neck, others believe it can contribute to Carpal Tunnel Syndrome. This injury, one of the most serious repetitive stress injuries (RSIs), is caused by compression of a nerve within the wrist and hand.

Because of reliance on the mouse in many applications, experts suggest selecting a mouse that comfortably fits the hand, with the buttons falling “naturally” under the fingers. When moving the mouse, the forearm, wrist, and fingers should be kept straight (that is, in line with the mouse). Some people may prefer the use of an alternative pointing device (such as trackball or “stub” within the keyboard itself, often found in laptop computers).

A variety of so-called ergonomic chairs of varying qual-ity are available. Such a chair can be a good investment in worker safety and productivity, but for best results the chair must be selected and adjusted after a careful analysis of the individual’s body proportions, the configuration of the workstation, and the type of applications being used. In general, a good ergonomic chair should have an adjustable seat and backrest and feel stable rather than rickety.

The operating system and software in use are also important. Providing clear, legible text, icons or other controls and a consistent interface will contribute to the user’s overall sense of comfort, as well as reducing eye-strain. It is also important to try to eliminate unnecessary repetitive motion. For example, it is helpful to provide shortcut key combinations that can be used instead of a series of mouse movements. Beyond specific devices, the development of an integrated design that reduces stress and improves usability is part of what is sometimes called human factors research.

In March 2001, President Bush cancelled new OSHA standards that would have further emphasized reporting and mitigating repetitive stress and musculo-skeletal dis-orders (MSDs). However, the legal and regulatory climate is likely to continue to place pressure on employers to take ergonomic considerations into account.