• Industrial Engineering and Management Systems
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• v.3 no.2
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• pp.140-150
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• 2004

Repetitive stress injury at the wrist has been reported as a common injury among visual display terminal (VDT) users (i.e., computer users). Adjusting a VDT workstation (computer table and chair) to maintain a correct seated posture while operating a keyboard is perhaps the most frequently recommended preventive solution. This paper proposes an analytical design methodology based on ergonomic design principles for recommending appropriate VDT workstation settings and layout of individual computer accessories on the computer table. The proposed design methodology consists of two interrelated phases: (1) determination of VDT workstation settings, and (2) design of computer accessories layout. Based on the information about the VDT user, dominant task to be performed, typing skill, and degrees of physical and visual interactions between the user and computer accessories, adjustment and layout solutions are recommended to allow having a correct seated posture while minimizing both physical and visual movements. The results from an experiment show that when adjusting the workstation and locating the computer accessories according to the recommendations given by the proposed design methodology, the user's hand movements can be significantly reduced.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.4
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• pp.459-465
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• 1999

A new-concept VDT workstation chair with adjustable keyboard/mouse support was proposed to minimize physical discomfort and the risk of cumulative trauma disorders (CTDs) at work sites in this study. First, a three-dimensional human modeling tool $(SAFEWORK^{(R)})$ was used to design the new chair satisfying the anthropometric specifications of Korean population. Second, based upon the result of 3-D graphical simulation, a mock-up chair was constructed with an adjustable keyboard/mouse support directly attached to the chair body. Third, muscle fatigue and subjective discomfort were measured to evaluate the newly developed chair. An experiment was conducted to compare the new workstation chair to the traditional computer chair without keyboard/mouse support. Six volunteer subjects participated in six one-hour word-processing sessions with two different chairs and three different postures. Statistical results indicate that the new-concept VDT chair generally improved subjective comfort level and reduced fatigue in finger flexor/extensor and low back muscle. In conclusion, this new VDT workstation chair is expected to reduce physical discomfort and prevent occupational CTD problems in the long run. Implications of the new design and suggestions for the further development are also addressed.

• Journal of Korean Institute of Industrial Engineers
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• v.32 no.3
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• pp.236-241
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• 2006

Monitor height is one of the key factors in the VDT workstation design. Most of the previous studies have focused on traditional VDT workplace where the operators performed data entry or word processing tasks using single monitor. This study aimed to suggest proper monitor height when the main task was monitoring information from different number of information sources. Twelve male students participated in three experiments: single information source (one monitor), two information sources (one monitor and one CCTV), and three information sources (one monitor, one CCTV and a window). Subjects performed monitoring tasks for 10 minutes with 3 different monitor center heights : 89.0 cm (Low), 111.3 cm (Middle), and 124.8 cm (High). Surface EMG signals of five neck muscles, subjective discomfort ratings, preference, and working postures were recorded. Results indicated that the middle height was proper for one monitor condition, but the low monitor height was recommended for more than two information sources.

• Archives of design research
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• v.12 no.1
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• pp.157-166
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• 1999

With the increase in use of the computer, the VCT syndrome has occured as a new socialJhea/health problem. ErgonomicaI design standards are a for the users to reduce stress and poor physical posture in the human body. In this study. we have suggested design dimensions recommended from previous studies. We also have reviewed users' preference dimenision, and analyzed differences between users' preference dimenision. and the previous design aiteria to verify physical appropriateness. We analyzed how each design dimension was reached and affected the tunan body by objective EMG evaluation. and subjective evaluation of physical discomfort and oorrIort. We have found that keyboard height is very important in a workstation. If the elbow's height is lower than the keyboard's height. it effedS the hand and wrist. If higher, it brings fatigue to the shoulder and neck. As a result of this experiment. we suggested that the height of a keyboard desk for Koreans be 660mm for the fixed type and 540-774mm for the adjustable type. Also other design reoommendations were suggested in the thesis. In ooncIusion, our research will be very important in the database because it provides adjustable ranges to fit user's body types in the various design flekIs.

• Proceedings of the ESK Conference
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• 1996.10a
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• pp.3-6
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• 1996

Cumulative trauma disorders (CTDs) are becoming a major health hazard among phone directory service operators. In order to clarify the causes and to reduce the occurrence of CTDs, a site survey was done. The survey includes observation of the task and the working environment. Also, operators were closely examined and diagnosed to understand the exact causes of CTDs. Different types of CTDs were identified and the most cases were developed in a two or three-years after using new VDT-based workstations. The various design features of workstation aggravated the developemtn of CTDs together with the intense workload. The ergonomic resolutions were suggested based upon these observations.

• Journal of the Ergonomics Society of Korea
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• v.32 no.5
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• pp.469-474
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• 2013

Objective: The purpose of this study was to analyze the risk factors of MSDs for the types of office work. Background: Physical risk factors of VDT(Video Display Terminal) associated with shoulder and neck musculoskeletal disorders(MSDs) include static work postures and workstation status. Method: In this study, office work was divided into data search, data entry and design work(drawings, etc.), and then we were surveyed 7 major work places which was included these works. We recorded working postures and obtained still images, depending on the types of office work. Then, RULA(Rapid Upper Limb Assessment) and ROSA(Rapid Office Strain Assessment) were used to analysis the risk factors. Results: The results of RULA showed that design work was under risk levels and required change, but ROSA showed that data entry and design work were high risk. The RULA is to evaluate the level of risk factors based on the working posture; on the other hand, the ROSA is to consider the use of peripheral, same as chair, keyboard/mouse, monitor and computer workstations. Conclusion: Conclusions of this study, the office work is necessary to identify the risk factors caused by the use of peripheral, as well as working posture.