From The Ergoweb® Learning Center

Revised ANSI/HFES Computer Workstation Ergonomics Standard Nearly Ready for Review

Workplace use of computers has increased dramatically since 1988. According to the United States Census Bureau, one-half of all adults in the US now use computers in the workplace. Many spend the majority of their day engaged in computer work. The same source noted that approximately three-fourths of all school age children use computers. At the same time that the number of users has increased, the means of interacting with and using computers has also changed. As computers become fixtures in more and more workplaces, the needfulness of developing and maintaining technical standards to derive the maximum benefit from computer use is readily apparent.

Since publication of the ANSI/HFS 100 standard in 1988, the Human Factors and Ergonomics Society (HFES) has been engaged in the further development of technical standards for use by individuals concerned with the design and use of computer workstations. Standards Action, the publication of record for the American National Standards Institute (ANSI), noted on January 25 the impending publication of the revised successor to the 1988 US standard for computer workstations, BSR/HFES 100, Human Factors Engineering of Computer Workstations (trial use standard.). (BSR is the acronym for “Board of Standards Review”). The document will be published for public review and comment at the end of March 2002.

The new document recognizes the increasing importance of computer workstations and the consequent benefits to users and employers of users from computer workstations that are ergonomically designed and integrated to enhance productivity and user comfort. The document provides guidance to designers as to how to accommodate variation both in the size of individual users and variation in the manner of usage. It also provides guidance to the individuals who must integrate individual workstation components designed for a wide variety of users into a system that fits the intended individual user.

In the previous version of the standard, only one reference posture, upright seated, was discussed. Unfortunately this sometimes led to the mistaken conclusion that it was the only correct working posture. There are four primary reference postures in the revised document: upright seated, reclined seated, declined seated, and standing. The upright seated and standing reference postures are already familiar; the reclined seated posture occurs when the backrest of the chair tilts backward from the vertical, the declined when the seat tilts forward (below horizontal). These four reference postures represent the variety of postures likely to be used by computer users rather than an exhaustive listing of all acceptable postures. These four reference postures primarily address trunk and leg posture. The revised document provides similar guidance to designers with regard to expected postures of other body parts, e.g., the neck, arms and hands.

Given these postural design parameters, the document sets a goal of defining workstations that will accommodate, at the least, a population ranging between the US 5th percentile adult female and the 95th percentile adult male. However, existing anthropometric data did not readily yield the information necessary to specify all the pertinent dimensions for all the reference postures, at least not without running afoul of the fallacy of adding percentiles. Accordingly, new methodologies of combining existing anthropometric dimensions were utilized. As a result, more accurate specifications were developed for relevant workspace dimensions. These methodologies are published in the draft for the use of those who wish to adapt the workspace dimensions to other anthropometric data.

Input and display devices are also addressed in the current revision. Previously keyboards were the only input devices discussed. The current version includes a discussion of non-keyboard input devices. Similarly, the display section has been expanded to cover both color and flat-panel displays.

The impending publication of the draft standard for trial use will begin the process of public comment. Individuals who wish to comment are invited to do so. As comments are received, the document will be revised as necessary and then submitted to the ANSI review process.

Copies of BSR/HFES100, Draft Standard for Trial Use, will be available in
early April from the Human Factors and Ergonomics Society, P.O. Box 1369,
Santa Monica, CA 90406-1369, USA; 310/394-1811; fax 310/394-2410; The price will be $50 for HFES members and $85 for

The revision represents the collective effort of many individuals over a period of many years. The donation of their time and knowledge, and the support of their employers, is deeply appreciated by the Human Factors and Ergonomics Society.

Contributed by Tom Albin, Master Ergonomist, Auburn Engineers, and Chairperson of the HFES/ANSI 100 committee