The purpose of this study was to investigate the health conditions of occupation group and hobby group related to visual display terminal (VDT) syndrome. The VDT occupation group was mainly composed of the worker in banks, telephone companies, and general offices. The VDT-related hobby group was composed of high school students, and Internet cafe users. A questionnaire survey was conducted to classify the subjects according to hours of computer usage. The results indicated that the occupation group represented a higher level of subjective symptoms than VDT-related hobby group. In the VDT occupation group, ‘Poor body condition’, ‘Feeling uncomfortable or pain in the neck’‘, Feeling uncomfortable or pain in the back’‘, Feeling stressed out’, and‘ Feeling uncomfortable or pain in the shoulder’ items indicated a high level of subjective symptoms. In the VDT-related hobby group, ‘Feeling uncomfortable or pain in the neck’, and‘ Feeling uncomfortable or pain in the back’ items indicated a high level of subjective symptoms. According to the hours of computer usage, 4-6 hours and 6 hours or more groups represented a higher level of subjective symptoms than 2-4 hours group. These findings suggest that Visual display terminal (VDT) work effects the individual's health conditions.

Background: Recently, there has been an emphasis on the use of interventions with biofeedback information for the maintenance or correction of posture. Objects: This study assessed the change of trunk posture and trunk muscle activation when people exhibiting postural kyphosis performed visual display terminal work with or without a contact feedback device (CFD). Methods: Eighteen right-handed individuals were recruited. Thoracic angle and right thoracic erector spinae (TES) muscle amplitude were analyzed. There were two sessions in these experiments. The control session involved 16 minutes of typing without a CFD, and the CFD session involved 16 minutes of typing with a CFD. The visual analog scale score was analyzed with a paired t-test, and the kinematic and electromyography data were analyzed through two-way repeated analysis of variance. Results: The paired t-tests revealed that subjects had significantly less pain after the CFD sessions than after the control sessions (p<.05). Significant main effects by session and by time were observed in the thoracic kyphosis angle (p<.05). There was a significant session×time interaction for TES amplitude (p<.05), along with significant main effects by session and by time (p<.05). Conclusion: The CFD caused people with postural kyphosis to straighten and to activate their TES continuously, even though they were habituated to bend their bodies forward. Therefore, the CFD was a beneficial treatment tool

In this study, we examined the effects of background and underline on the readability of displayed text The background was placed on every other line and the underline was done with every line of the text The effect of adding color to the background and u

The purpose of this study was to examine the relative effectiveness of immediate feedback and informational prompt on safe sitting behaviors that may cause VDT syndromes. Participants were three white color workers and an ABCB within-subject design was adopted. Safety Posture System was developed specifically for the present study. The system could detect participants' unsafe sitting postures using sensors and provide feedback and prompt on the computer monitors. The results indicated that both immediate feedback and informational prompt considerably increased safe sitting behaviors. More importantly, the immediate feedback was more effective than the informational prompt in increasing safe sitting behaviors.

This study was to investigate the relationship of VDT(visual display terminal) work condition and fatigue severity in the financial office workers. Questionnaires were completed by 662 persons in VDT workers of Post Office from January to May 2006. Multidimensional Fatigue Scale(MFS) that was developed in Korea Occupational Safety &Health Agency to estimate the degree of fatigue was used for study. In results, 149 persons(22.5%) in VDT workers were felt low fatigue severity, 351 workers(53.0%) were middle, and 162 workers (24.5%) were high. So it was appeared that one in four VDT workers felt the high fatigue severity. And woman VDT workers felt more fatigue severity than man. Also, fatigue severity was increased with increasing work time. Our findings suggest that VDT workers in financial office need proper health program to prevent occupational fatigue and disease.

To investigate characterization of EMF(Electromagnetic Field) emission from VDT(Visual Display Terminal) in computer room, we were divided into 3 types of placement monitors which are 1) back side of monitor faced the ground(back view type), 2) arrangement of monitors was a line type(two sides type), and 3) disposition of monitors was s straight(horizontal line type). We also measured monitors classified types at the front, side and back by distance and evaluated by TCO(The Swedish Confederation of profession Employers) and MPR-2(Measure and Proof Radiation Board) guide line. Magnetic field emission level by the type of VDT, it was indicated that MF(Magnetic Field) level was below the backgrounds level when CRT moved away about 70~90cm, LCD moved away about 40~50cm. We evaluated MF emission level by the number of VDT, it did not show any relationship. Finally, estimated MF emission level by the placement of VDT, it was showed the MF level less than the background level, when VDT moved away 40~50cm in all dispositions with exception of 2 sites. Background level of case was higher than emitted from VDT, so that did not effect on MF level by distance. However, we find out that as distance increased, MF emission level decreased significantly in all cases. We measured MF emission level of one monitor and others (back and forth) monitor in line type. Below the background level when one monitor type moved away 70cm, others monitor type moved away 40cm. However, other monitor types affected MF level which is located back monitor. The data demonstrate that avoiding excessive MF exposure from VDT using computer room, to have a space between user and VDT at least 50㎝.

In large scale complex system such as a nuclear power plant, it is important to select guidelines and/or checklist to evaluate the system performance, especially human performance for visual information while the number of evaluation items of the guidelin

Back pain is painful for people at a lower lumber(L4/L5 or L5/S1). It is experienced as a most frequent disaster 70％ of workers have suffered from back-pain. Especially, the occurrence rate of back pain for nurses is very high. Therefore, this study investigates female nurses who worked as a part of a medical cost management team, which mainly deal with the medical insurance in a general hospital at Seoul area. These nurses had different job tasks, which used computers for 50％ of their time, so it can be treated as VDT workers. As a first step of this project, a muscle fatigue was measured for these special VDT workers. First, survey for nurses was conducted to figure out what is a real problem of them. Second, to evaluate an experimental data, a medical cost management team was chosen for subjects. Areas of measurement were 3 places that were the trapezius (TR), the medial deltoid (MD), and the erector spine muscle (ES: L4/L5). These areas are most frequently used, so they were chosen for this study. Measurements were taken before work and after work. From these measurements, it was revealed that a fatigue really comes from their main VDT task excluding natural fatigue after work, so their work environment need to be corrected.

18세에서 30 세 중반 사이의 남자 35 명 여자 21 명 총 56명올 대상으로 2시간 동안 VDT 작업을 하도록 한 후， 안구 및 전신 중상 둥율 조사하고 순목 횟수， 눈물층파괴 시간 (BUT) ， 안겸열의 높이， 시력， 타각적 굴절력， 조젤력 둥올 측정하였다. 안구증상 에서는 눈의 피로를 느끼는 사람이 34% 로 가장 많았고 시가능증상에서는 물체가 흐 려 보이는 증상이 83%, 전신증상에서는 어깨가 아픈 사람이 38%로 가장 높게 나타 났다 VDT 작업 중의 순목 횟수가 8/min로 휴식 때의 22/min 에 비해 많이 감소했 다. VDT 작업 직후의 눈물층파괴시간도 약 7초로 작업 전의 약 12초보다 현저히 감 소되었다. 안겁열의 높이는 작업 전 7.69mm보다 작업 중에는 9.04mm로 증가하였 다. 평균 나안시력은 VDT 작업 전에 0.63에서 작업 후에는 0.57로 약 9.5% 감소하는 겸향을 보였고， 타각적 끊절이상은 0.28D 정도 끈시화 경향올 보였다. VDT 작업 후 조절력은 1.49D 정도 감소하였는데 주로 조절끈점 끓절력의 감소가 원인인 것으로 보고， 폭주근점 꿀절력도 0.87D 감소하였다.