• 항공우주의학회지
• /
• 제30권2호
• /
• pp.61-65
• /
• 2020

In the case of aviation maintenance work, several kinds of shift works are performed during day and night, and a lot of works are performed on the ramp due to the characteristics of the aircraft flight schedule. Maintenance workers are often exposed to the sun or in cold temperatures for aircraft maintenance works. The fatigue risk of the maintenance workers will be weighted. In particular, the work at night shift under normal biological rhythms can make maintenance workers feel sleepy during daytime work. It can also affect the safety of aircraft and individual workers. Accordingly, this study will consider fatigue-related previous researches in the field of aviation maintenance, review the effects of shift work, and how fatigue affects aviation mechanics during the day/night shifts. Considering these factors, we tried to present a plan that can minimize the fatigue of aviation workers through this study.

• 대한영양사협회학술지
• /
• 제29권1호
• /
• pp.13-30
• /
• 2023

This study investigates the effect of working hours on the dietary behaviors and dietary quality of male industrial workers employed in rotating shifts. The survey was conducted from February to March 2022, enrolling 209 male workers operating in rotational shifts at industries in the Chungcheongnam-do region. Eating behavior and health awareness were investigated during the morning shift, afternoon shift, and night shift for the same subjects. The shift timings were found to be associated with dietary behavior, which had an impact on the dietary quality of workers. Negative effects of shift timings on diet and health were also perceived by the shift workers. The frequency of alcohol consumption was high during the morning shift, and the frequency of night time snack intake was high during the afternoon shift. During the night shift, there was decreased vegetable intake and increased ramyeon intake. Compared to the morning shift, a significant decrease in dietary quality scores was found during the night shift. The workers recognized that rotating shift work negatively affected health, eating habits and sleep. There was a high demand for providing a variety of menus and healthy night snacks in the company cafeteria. When nutritional counseling and educational health services were provided, the willingness to participate was high. Therefore, to improve the health and dietary quality of shift workers, there is a need to provide diets suitable for the working environment and the characteristics, and to provide nutrition management services.

• Nutrition Research and Practice
• /
• 제8권4호
• /
• pp.432-438
• /
• 2014

BACKGROUND/OBJECTIVES: This research was conducted to develop a construct model regarding the dietary style, late night snacking choice attributes and health promotion behaviors of industrial workers. SUBJECTS/METHODS: The surveys were collected during the period between January and February 2013. A statistical analysis of 888 industrial workers was conducted using SPSS 12.0 for Windows and SEM (Structural Equation Model) using AMOS (Analysis of Moment Structure) 5.0 statistics package. RESULTS: The results of the correlations between all variables showed significant positive correlations (P < 0.05). Results of factors analysis on dietary styles were categorized into five factors and health promotion behaviors were categorized into four. The reliability of these findings was supported by a Cronbach's alpha coefficient of 0.6 and higher for all other factors. After obtaining the factors from processing an exploratory factor analysis and the end results supported the validity. In an attempt to study the late night snacking choice attributes in accordance to dietary styles and the health promotion behaviors of industrial workers, a structural equation model was constructed and analyzed. CONCLUSIONS: All tests proved the model satisfied the recommended levels of the goodness on fit index, and thus, the overall research model was proved to be appropriate.

• Journal of Preventive Medicine and Public Health
• /
• 제37권2호
• /
• pp.182-189
• /
• 2004

Objectives : The objective of this study is to compare the circadian patterns of heart rate variability assessed by 24-hour ambulatory electrocardiographic (ECG) recordings during day shift and night shift among the workers in the 5 days-concecutive-12-hour shift in an automobile factory in Korea. Methods : The study population consisted 300 workers, who were randomly selected among the 8700 total workers in one car factory. To analyse circadian variation, the 24-hour ECG recordings (Marquette) were measured during day shift (08:00-20:00 h) and night shift (20:00-08:00 h). Analysis was performed for all time and frequency domain measures of HRV. 233 workers completed taking 24-hour ECG recordings. Results : This study shows that the 24 hourcircadian variation mainly follows work/sleep cycle rather than day/night cycle among shift workers. This study also shows that among the night shift, the circadian variation between work and sleep cycle decreased compared to the work/sleep cycle among day shift workers. All time and frequency domain parameters (except LF/HF ratio) show significantly different between work and sleep in the day shift and night shift. Conclusion : These changes in heart rate variability circadian rhythms reflect significant reductions in cardiac parasympathetic activity with the most marked reduction in normal vagal activity among the shift workers. Especially, it suggests the circadian rhytm has blunted among the night workers. The quantification of the circadian variation in HRV can be a surrogates of workers' potential health risk, as well as suggests possible mechanisms through which the shift works compromise workers' health.

• 대한산업공학회지
• /
• 제30권3호
• /
• pp.181-189
• /
• 2004

The purpose of this study was to investigate the effects of sleep/wake behavior for shift workers in the iron and steel industry using wrist actigraph for 59 male workers on a continuous full-day three-team three-shift system of backward rotation including on-duty and off-duty periods. The wrist actigraph data were recorded for 15 days (l shift cycle) for each subject. The sleep length at home during night shift decreased significantly as compared to the morning or evening shifts. The night shift nap length increased significantly in all sections as compared to the morning or evening shifts. The nap length in the Steel Manufacturing Process and Rolling Process during night shift decreased significantly as compared to the Machine Maintenance Section, the Forwarding of Products Section, and the Field Management Section. However, the sleep length at home while off-duty period increased significantly. The percentage of nap length during night shift in the Rolling Process, Steel Manufacture Process, and the other three types of jobs was 16.0%, 20.4%, and about 50.0%, respectively. The nap length during night shift for the above 50 year olds increased significantly as compared to the below 50 year olds. Finally, we discussed the role of nap-taking during the burden on night shift workers and the increased difficulty in continuing their job.

• 대한인간공학회지
• /
• 제22권3호
• /
• pp.13-26
• /
• 2003

The purpose of this study is to investigate the present conditions of the night work and shift work systems in the heavy chemical industrial complexes found in Changwon, Masan, and Chinhae. Korea. We will attempt to define and classify their problems; and to discover further ways to improve their systems. Fifty production factories were carefully selected as the subjects for this study. The shift systems were classified into five categories. The consecutive night shifts were long in almost all cases with 6 days (36 factories) and 7 days (13 factories). It was found that the night work of about] 2 hours continues for a long period in the weekly rotation full-day shift systems and the night-including non-full-day shift systems, and there was no holiday during a shift cycle in the continuous full-day shift systems. The work time in most shift systems was longer than the 44-hours/week permitted by Korean law. Considering the characteristics of these various types of shift systems, the most essential thing to reduce the shift workers' work load may be to shorten their working hours and improve the schedule of shift systems. It is highly recommended as a fundamental solution. to reduce the portal-to-portal hours from 12 to 8 in the night-including non-full-day shift systems and the weekly rotation full-day shift systems, and at least to employ a 4-team 3-shift system in the continuous full-day shift systems. In addition to this, it should from now on be taken as a goal to restructure the types of shift systems by taking such measures as avoiding continuous night work if possible, providing sufficient off-duty intervals both before and after night shift, providing increased opportunities for workers to nap during night work. and increasing the number of holidays.

• Journal of Korean Biological Nursing Science
• /
• 제2권2호
• /
• pp.81-89
• /
• 2000

To determine the optimal rotational shift system, the effect of the direction of the rotational work shifting on the nocturnal rhythm of plasma melatonin were investigated in nursing students. Two groups of nine volunteers participated as experimental subjects, and two nursing students participated as a control group. The directions of the rotational work shift were as follows: CW(clockwise)-shift were rotated in the direction of day shift(3 days), evening shift(3 days), off duty(1 day) and night shift(5 days), and CCW(conuterclockwise)-shift were done in the reverse direction. Plasma melatonin concentrations was measured by radioimmunoassay. The results were as follows : The plasma melatonin levels were kept low at night and in the following morning in the CW night shift workers, whereas the level started to increase at 05 : 00 hr in two workers of four CCW shift workers. These result suggests that the shift rotation in the CW direction is more acceptable in terms of the adaptation of hormonal rhythms. These results indicate that the CCW rotation of shift work is somewhat better than CCW rotation for the adaptation to shift work on hormonal aspects in nurses.

• 대한가정학회지
• /
• 제27권1호
• /
• pp.47-58
• /
• 1989

This study was undertaken to investigate whether the stress caused by day/night shifts on industrial workers can be affected through nutritional status. A sample of 573 female industrial workers, aged 17 through 23 years, from 4 different industries (2 in normal, 2 in 3 shift work pattern) were surveyed by questionaire examining their nutritional status, food intake, dietary habit, sleep complaint, performance of digestive organs, and degree of fatigue. Shift workers were surveyed during night work. The results are summarized as follows: 1. Sleep complaints and degree of fatigue in shift workers were higher than normal workers, whereas the performance of digestive organs were as lower than normal workers. These results showed that shift workers were more stressed than normal workers. 2. The workers who were surveyed were all poor in nutritional status. The intakes of calorie, protein, Ca, riboflavin, and ascorbic acid were lower than Korean Recommanded Dietary Allowences (RDA). Dietary habit of the shift workers was irregular. 3. There was a negative correlation between nutritional status and degrss of fatigue. The intakes of energy nutrients, ascorbic acid, and niain were significantly related to the degree of fatigue in which protein intake was found to be most influential. Among workers with the same level of protein intake, shift workers showed higher degree of fatigue. When the protein intake of shift workers was 100-125% of R.D.A., they showed the same degree of fatigue to the average normal workers.

• Journal of Preventive Medicine and Public Health
• /
• 제27권1호
• /
• pp.74-83
• /
• 1994

To investigate the sleeping patterns and gastrointestinal disorders of shift workers, the author studied 434 female workers who worked at textile industry ill Taejon city from September 1,1992 to September 31,1992. Shift pattern were divided into 3 categories ; 3 shift(shifts per 8 hours), 2 shift(day and night shift) and day work. The results obtained were as follows : 1 The average sleeping hours when adjusted for the education level of the total study subjects was 6.1 hours. That of 3 shift workers was 6.1 hours, 2 shift workers was 6.0 hours, but that of day workers was 6.5 hours. There were no significant difference among the shift workers. 2. For the 3 shift workers, the average physiologic adjusted duration in day shift (2.2 days) was shorter than that of night shift(2.7 days) and there were significant difference among the rotating shift works (p<0.001). The sleeping problems in day shift was less than those of night shift (p<0.001). 3. 44.9% of 3 shift workers, 39.3% of 2 shift workers and 33.1% of day workers complained gastrointestinal symptoms when adjusted for the age, education level, job tenure, work post. And the rates of gastrointestinal symptoms complained increase with job tenures (p<0.001). 4. The most frequent gastrointestinal diseases were gastitis and gastric ulcer with 14.2% , Irritable bowel syndrome with 3.1 %, duodenitis and duodenal ulcer with 2.1% and combined gastrointestinal disease with 2.1%. Age, eating habit, amount of coffee per day, job tenure, work post and shift pattern showed no significant difference with the gastrointestinal diseases when adjusted for the age. According to the above results, the author suggested that the shift pattern and job tenure can affect to the sleeping problem and gastrointestinal symptoms.

• Safety and Health at Work
• /
• 제11권3호
• /
• pp.361-366
• /
• 2020

Background: This study aimed to identify the validity of breast cancer symptom questionnaire of worker's special health examination and its relationship with breast ultrasonography findings in young female night workers. Methods: The breast cancer symptom questionnaire data of worker's special health examination and breast ultrasonography results in young female shift workers who worked in one electronic manufacture company were collected from 2014 to 2018. Results: Of the 857 workers, 18 had a Breast Imaging Reporting and Database System category 4 or higher. Among other variables, shift work tenure alone was associated with the risk of having a Breast Imaging Reporting and Database System category higher than 4. The sensitivity, specificity, positive predictive value, and negative predictive value of the symptom questionnaire were 16.7%, 87.7%, 2.8%, and 98.0%, respectively. Conclusion: The current breast cancer symptom questionnaire of the worker's special health examination is inappropriate due to its low sensitivity and positive predictive value. In the future, female night workers will need alternative measures for more accurate screening for breast cancer.