Proceedings of the Human Factors and Ergonomics Society Annual Meeting

The present study investigated the influence of control over the physical environment on individual performance, group effectiveness, and worker health. A new office workstation was design for knowledge workers with the intent of providing a highly adjustable, flexible physical work environment. It was hypothesized that the adjustable, flexible features of the new workstation would increase availability of control and workers' knowledge of control over their workstations. It was predicted that availability of control and knowledge of control would improve individual and group effectiveness, enhance group collaboration, and decrease stress and physical health problems. Results of the study indicated that when compared to standard systems furniture offices, the new highly adjustable workstation was found to increase the availability of control and that workers' knowledge of control both played a significant role in increasing individual performance and group effectiveness. Availability of control and knowledge of control were also found to improve group collaboration and decrease psychological stress. The design of the highly adjustable workstation enables users a degree of physical control beyond that of standard workstations, thereby increasing performance, collaboration, and psychological health.

Universal design is a very new area of design research. Because it has its roots in the design for disability or design for the aged, there is a belief that universal design is same thing, a new buzzword for an old idea. In reality, universal design is very different from both of them. Never before has a research clarified the differences between accessible and universal design. This pioneering research in the field of universal design uses empirical methods to evaluate bathroom designs and draw distinctions between universal and accessible environments. Measuring Universal Design is part of a research and development project, The Universal Bathroom. Its results provide information about the properties that make environments accessible or universal.

In this paper, we examine an approach to representing the impact of technological change on work practice. Taking Cognitive Work Analysis as a point of departure, we discuss an approach with which one can analyze work domains and work activities and then use these analyses as a ‘field’ upon which to trace the impact of new technology. The relation between activity and work structure is explored. Then, a case study of the introduction of an electronic anesthesia record is examined. Associated changes to work structures and activities are represented and interpreted. Finally, we discuss the implications of the work and future directions.

This study was designed to identify the postures assumed by Web users and to compare these postures to those assumed during conventional text-entry tasks. Twenty-four participants were observed while performing various Web and typing tasks on a standard computer workstation. Across all postural measures, there were many instances where Web browsing postures differed in kind or frequency from typing postures. Further, there were some postural variances attributed to the different requirements of the three Web tasks (searching vs. learning vs. browsing). Overall, many postures were observed during the course of Web browsing that can be classified as detrimental towards the development of cumulative trauma disorders (CTD). Based on the results of this study, we provide guidelines for improving the posture of Web users.

The four papers at this symposium describe leading-edge ergonomic research on the design of office chairs. Results from new studies on the dynamics of back motion and active sitting, the concept of spineprints, and their relevance to ergonomic seating design will de described. Work on the postural benefits of chair armrests, and their influence on wrist posture during keyboard use will be presented. The implications of these studies for rethinking the requirements for an ergonomic chair will be discussed.

The magnitude and rate of force required to maintain the body in a supported position throughout seated articulation will vary depending on the physical stature of the user and the seating mechanism. This study investigated five different chair mechanisms. The magnitude of force required to support the body throughout articulation, for a diverse population, was determined for each chair's mechanism. This requirement was then compared to the amount of support that the chair's mechanism was designed to produce. The relationships between the magnitude of force required by the user to maintain support throughout articulation and the magnitude of force provided by the chair mechanism is compared and evaluated.

The nature of job tasks in the office work environment has changed significantly since armrests were added to office chairs. This literature review examines applicable research in an effort to understand the importance of adjustable armrests and to distinguish some of the issues surrounding proper design features. Evidence suggests that adjustable armrest can relieve muscle activity and promote better seated posture in workers who use computer input devices as a regular part of their job.

The effects of four different chair armrest designs on typing wrist posture were tested. Twenty-four subjects, men and women grouped at the 95th, 50th, and 5th percentiles for height, typed while sitting on each of four chairs with different armrests. The chair armrest designs investigated differed by the type, number and range of adjustments available. Each subject typed while instrumented with wrist electrogoniometers that measured wrist extension/flexion and radial/ulnar deviation. All conditions and tasks were counterbalanced. Results showed no main effects of chair armrest design on either wrist extension or ulnar deviation. Significant interactions involving chair armrest design were found for ulnar deviation but not for wrist extension. Correlations between anthropometric dimensions and wrist posture were found.

The goal of this study was to use biomechanical procedures and models to measure people and office chairs in terms of fit, movement, and support during changes in recline and spinal curvature. Testing was performed with four office chairs in a simulated keyboarding workspace with fourteen subjects ranging from petite, light women to tall, heavy men.

Postures, body motions and chair motions were measured with a video-based system. A Lordosimeter measured changes in lumbar spinal curvature. Torso positions relative to the keyboard and desktop were evaluated for changes in recline angle and lumbar curvature. Pressure distributions were measured on the back of the chairs and related to changes in torso posture (back inclination and lumbar curvature). Based on the contact areas between the subject's back and the seat back, the amount of support was evaluated for changes in recline angle and lumbar curvature.

Chair D, the LEAP chair had the best overall performance. LEAP was found to move with people as they moved their spine from flexion to extension. During recline motions LEAP demonstrated a reduction in travel of the wrist and head as compared to the other chairs and a reduction in the pressure necessary to recline the seat, specifically in the shoulder region. The LEAP chair also provided a consistent pressure map for all test conditions, confirming that the chair maintained contact with the torso.