• Journal of the Korean Society of Safety
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• v.15 no.3
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• pp.108-114
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• 2000

The work posture impose additional stress upon human workers so that it should be carefully considered in designing works. However, we have a lot of manufacturing plants which convert their standing workplace to sedentary one. To confirm the validity of that trend, the authors conducted an experimental study, and compared the results. The results of the EMG and the self-cognitive symptoms, in general, showed a correspondent trend that the sedentary work posture was rated more comfortable. At the beginning of the work, complaint of the lowerback was higher whereas that of the lower leg and the feet went higher as the time elapsed. If the weight of workpiece were heavier than 500g, increasing rate of bodily discomfort in the sedentary posture were greater than that of the standing posture. In the meanwhile, the standing posture was consistently superior to the sedentary posture in its performance. Thus, in conclusion, for a light assembly work, sedentary work posture would be recommendable because bodily discomfort would be larger irrespective of the small increase of performance increase.

• Journal of the Korea Society of Computer and Information
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• v.22 no.6
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• pp.149-156
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• 2017

In this paper, we propose to enhance a Physical working conditions to decrease absence from work. we demonstrated the correlation of worker's absence with various environmental factors in workplace by surveying 6,962 workers. As result, first, concerning exposure to physical work factors, most of them complained of vibration, and concerning exposure to improper working posture, most of them complained of repetitive arm and hand motions. Second, the absence experience had correlations with age, monthly income, smoking, number of employees, long term working, and shift work, and of the physical factors, hand vibration, noise, high temperature, low temperature and improper working posture had correlations with physical pain posture, movement of people and carrying heavy materials. Third, experience of exposure to hand vibration, noise and low temperature of the physical factors had impact on absence, and of the improper working posture, physical pain posture and carrying heavy stuff had impacts on absence. Through this study, it was found that of the work factors of Korean workers, physical factors and improper working posture had impacts on absence. The results of this study confirmed that physical factors and inappropriate working posture among work factors influenced the absenteeism. Therefore, it is required to improve the work environment regarding physical risk factors and prepare a systematic management plan.

• Journal of the Ergonomics Society of Korea
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• v.24 no.3
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• pp.43-52
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• 2005

A two-dimensional posture measurement system was developed to evaluate the risks of work-related musculoskeletal disorders(MSDs) easily on various conditions of work. The posture measurement system is an essential tool to analyze the workload for preventing work-related musculoskeletal disorders. Although several posture measurement systems have been developed for workload assessment, some restrictions in industry still exist because of its difficulty on measuring work postures. In this study, an image recognition algorithm was developed based on a neural network method to measure work posture. Each joint angle of human body was automatically measured from the recognized images through the algorithm, and the measurement system makes it possible to evaluate the risks of work-related musculoskeletal disorders easily on various working conditions. The validation test on upper body postures was carried out to examine the accuracy of the measured joint angle data from the system, and the results showed good measuring performance for each joint angle. The differences between the joint angles measured directly and the angles measured by posture measurement software were not statistically significant. It is expected that the result help to properly estimate physical workload and can be used as a postural analysis system to evaluate the risk of work-related musculoskeletal disorders in industry.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.3
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• pp.171-181
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• 2009

This study was carried out to evaluate a musculoskeletal symptom and the work posture of the nurses in an operating room who have worked in the present department for more than one year. The job analysis of operating room nurses for ergonomic work posture analysis is divided into 14 tasks. On the basis of that, a survey research and ergonomic work posture analysis are also carried out. Among 41 operating room nurses of a cancer center in Kyonggi province who responded to the self-administered questionnaire, 20 nurses were observed and videorecorded to apply Rapid Entire Body Assessment(REBA) to ergonomic work posture analysis from April 16, 2007 to May 18, 2007. The results of analysis are as follows. The prevalence rate of musculoskeletal symptoms was 75.6% and its prevalence rates by part of the body are these followings; lower back and leg/foot 43.9%, shoulder 36.6%, neck 34.1%, hand/wrist/ finger 22.0%, arm/elbow 14.6%. In accordance with the results of ergonomic work posture analysis, 4 tasks that have a REBA score of 8 have high-risk levels and require an immediate management. It shows there is a significant correlation with overall musculoskeletal symptoms and objective workloads that are estimated by REBA. In conclusion, the work conditions of operating room nurses should be improved. It is also necessary that inappropriate work postures and ergonomic work conditions are improved to prevent musculoskeletal disorders of operating room nurses.

• Journal of the Ergonomics Society of Korea
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• v.33 no.2
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• pp.167-174
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• 2014

Objective: This research focuses on the working environment of office workers and aims to propose an ideal seating posture and chair design. Background: Generally, office workers having to seat in a fixed posture for long periods of time tend to suffer from an increased rate of musculoskeletal disorders. Method: The measurement and survey of 123 office workers on their working conditions and literature survey will lead to a suggestion of an ideal seating posture and workstation design theory. Results: Work environment satisfaction appeared low for chair and desks. Work-related pain over the last year was experienced among 47.2% of the respondents in shoulder (34.2%), neck (30.9%). Observation of working posture revealed that only 27.6% of workers utilize backrest during work. Conclusion: Office work embodies many situations where risks of musculoskeletal disorders may be high. Thus, the seated workplace must be set up to allow proper seating posture for workers. Application: The results of this study can be applied as baseline data for preventing musculoskeletal disorders of office workers.

• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.565-577
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• 1996

This study was conducted to evaluate the association of work posture with cervical spine abnormality toward 106 microwave-oven assemblers. A self-administered questionnaire was used to obtain a general characteristics and a work history of workers. The posture of neck and shoulder joint of workers were measured with video tape recording and the simple X-ray of cervical spine was checked-up to observe the X-ray abnormality including degenerative change, curvature abnormality, disc space narrowing or disc canal narrowing. The result were as follows. 1. The prevalence of degenerative change among cervicobrachial disorder workers was 44.3% (47 persons), curvature abnormality was 43.4%(46 persons), disc space narrowing was 21.7%(23 persons), and disc canal narrowing was 21.7%(23 persons). 2. The prevalence of degenerative change at cervical spine was increased with the degree of neck flexion(flexed versus neutral, odds ratio [OR]=2.7), the total work posture of neck(mild or severe awkward versus neutral ; OR=1.2, 3.4). 3. The prevalence of degenerative change at cervical spine was increased with the degree of the right shoulder flexion, the heaviness of the materials carried by the right hand and the degree of awkwardness at the total work posture of right shoulder(p<0.05). 4. There was no evidence of association between curvature abnormality, disc space narrowing, disc canal narrowing and work posture. In conclusion the awkward work posture was related with degenerative change of cervical spine among microwave oven assembling workers and the further study in these field must be made to prove the association objectively.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.375-382
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• 2019

Objectives: This study was to examine the features of work and posture analysis outputs in assessment of exposure to musculoskeletal disorder (MSD) risk factors in general hospital nurses. Methods: Work and posture analyses were carried out using observational approaches for nurses at general hospitals across Korea. With development of a taxonomy for assessing exposure to MSD risk factors, nursing tasks were documented in frequency (%time) for 8 hours a day in work analyses. Rapid Entire Body Assessment (REBA) scores were obtained for mode and maximum risk levels, respectively, during posture analyses. Results: A total of 27 nurses were observed while conducting 7 nursing tasks at 6 general hospitals. For both the work analyses and posture analyses, the taxonomy was developed and used. In the work analyses, 'Video display terminal task' and 'Nursing examination/ treatment' were the highest as 25%time for 8 hours a day, followed by 'Patient care' and 'Room rounding' as 13%time in order. In the posture analyses, the mode REBA scores were 2 or less for all nursing tasks while the maximum REBA scores were 7 for upper limbs at 'Room rounding' and 6 for trunk/neck/legs at 'Patient care'. Conclusions: The results showed the study nurses are occasionally at a risk for MSD, a medium level as designated in the REBA risk level, suggesting that it is important to control awkward posture at the nursing tasks such as 'Room rounding' and 'Patient care', in priority, for preventing MSD in the hospital sector including the study general hospitals.

• Journal of the Ergonomics Society of Korea
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• v.24 no.1
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• pp.37-41
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• 2005

Work related musculoskeletal disorders became a hot issue in Korea since many workers reported musculoskeletal disorder problems. Korean government enacted a law to require companies to take measures to prevent musculoskeletal disorders at work. This study found workers' WMSDs symptoms in squatting work posture which the rate of the occurrence was relatively high among work types to bring about WMSDs in railroad cars maintenance works and analyzed to compare the hazardous jobs in the industrial safety health law in South Korea with the caution jobs in Washington State in U.S. The hazardous jobs in South Korea were more effective in squatting work posture from this study result and this study data will be a great help to plan and carry out an effective prevention program about WMSDs.

• Journal of the Ergonomics Society of Korea
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• v.32 no.1
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• pp.145-152
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• 2013

Objective: The aim of this study is to develop an ergonomic office chair that has an alarm function for the unbalanced sitting postures. Background: Contrary to expectation, it is reported that office workers sit on their chairs much more in unbalanced postures during daily work. Even though an office worker uses an ergonomically good-designed chair and begins their work in a good sitting posture, his/her posture is likely to shift to the unbalanced bad posture. Therefore, a posture alarm system would be very helpful in keeping office workers' good postures. Method: We developed a prototype chair with four load cells under a seat pan and one load cell beneath a backrest. Through some experiments, we set the criteria for unbalanced bad postures then implemented the criteria into the alarm system of the prototype chair. The chair called e-BASE chair could detect unbalance postures and show alarms for chair users. We also enhanced back support by developing a step-wised folding backrest. Results: The e-BASE chair showed better performance in interface pressure distributions and balanced posture ratio in VDT work. Conclusion: The ergonomic chair with posture alarm function(e-BASE chair) was developed. It showed better performance in seat pressure distribution and in keeping good posture during office work. Application: The posture alarm system and folding backrest can be applied to the new models of office chair.

• Safety and Health at Work
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• v.5 no.1
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• pp.27-31
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• 2014

Background: Carpal tunnel syndrome (CTS) is a common work-related peripheral neuropathy. In addition to grip force and repetitive hand exertions, wrist posture (hyperextension and hyperflexion) may be a risk factor for CTS among workers. However, findings of studies evaluating the relationship between wrist posture and CTS are inconsistent. The purpose of this paper was to conduct a meta-analysis of existing studies to evaluate the evidence of the relationship between wrist posture at work and risk of CTS. Methods: PubMed and Google Scholar were searched to identify relevant studies published between 1980 and 2012. The following search terms were used: "work related", "carpal tunnel syndrome", "wrist posture", and "epidemiology". The studies defined wrist posture as the deviation of the wrist in extension or flexion from a neutral wrist posture. Relative risk (RR) of individual studies for postural risk was pooled to evaluate the overall risk of wrist posture on CTS. Results: Nine studies met the inclusion criteria. All were cross-sectional or case-control designs and relied on self-report or observer's estimates for wrist posture assessment. The pooled RR of work-related CTS increased with increasing hours of exposure to wrist deviation or extension/flexion [RR = 2.01; 95% confidence interval (CI): 1.646-2.43; p < 0.01: Shore-adjusted 95% CI: 1.32-2.97]. Conclusion: We found evidence that prolonged exposure to non-neutral wrist postures is associated with a twofold increased risk for CTS compared with low hours of exposure to non-neutral wrist postures. Workplace interventions to prevent CTS should incorporate training and engineering interventions that reduce sustained non-neutral wrist postures.