• 대한인간공학회지
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• 제33권6호
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• pp.487-497
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• 2014

Objective: This study aims to develop and evaluate a multi-purpose rollator, which may be used as a seat, as a traditional walker, or as a storage basket for elderly farmers. Background: The rollators on the market are not user-friendly designed and seen inconvenient for elderly farmers to use, although they are sold at considerably high price. Since they lack enough space to load stuffs and are not durable or stable enough, they do not seem to be suitable for elderly farmers to use in rural areas. Method: Two types of methods were used in this study. First, the survey consisted of 19 questions was conducted among elderly farmers in rural areas, after using the developed rollator, to evaluate the usability of the rollator developed in this study. Second, EMG experiment was conducted to compare the existing rollator and developed rollator quantitatively. Through this experiment, we tried to verify the differences of muscle responses, when using the traditional and the developed ones, which have their own brake system, in the ramp. Results: The developed rollator was highly evaluated in most of the questions in the usability survey, except for the 'Weight' category in which the opinions were divided into three different types (Worse: 31%, Similar: 30%, Better: 36%). The result of EMG experiment showed that the existing rollator (7.4%MVC) demands more muscle strength than the developed rollator (5.5%MVC) does. By statistically analyzing the results of upper limb and lower limb respectively, we found out that all the muscles except deltoid in upper limb showed statistically significant differences in muscle activity when using the existing and the developed rollator. However, there was no statistical difference in lower limb muscles. Conclusion: The developed rollator in this study has maximized the functionality of the brake system, the storage and the chair, which were pointed out as the weaknesses of existing rollators. Furthermore, the developed rollator is designed to be more user-friendly, safe, durable, and effective for elderly farmers to use in rural areas, where roads are rough and bumpy. Application: We expect that the emergency brake system developed in this study would be utilized for other convenience equipment, such as strollers and carts, and that it would be able to develop and produce more secure and reliable equipment in the future.

• 대한인간공학회지
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• 제29권6호
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• pp.933-942
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• 2010

Objective: To develop an ergonomic evaluation tool which can be apply to assess the lower-limb postures associated with farming tasks. Background: In general, most of existing ergonomic assessment tools was developed to investigate the work-related musculoskeletal disorders of the upper-limb postures in manufacturing industry. Methods: As the first step of development of the evaluation tool, 13 lower-limb postures that were commonly observed in farming task were investigated by the subjective discomfort ratings, heart rates, and muscle activities. And then, an ergonomic evaluation tool for the lower-limb postures was developed based on results of the first experiment. Lastly, the ergonomic checklist which was developed in the current study was compared with other existing ergonomic assessment tools. Results: Based on the results of comparisons between a newly developed assessment tool and other existing assessment tools, it was found that a newly developed tool can perceive more sensitively for the various lower-limb postures than other assessment tools. Conclusions: Lower-limb posture assessment tool which can evaluate and assess risks of lower-limb WMSDs which were prevalent in farming tasks more easily and accurately was developed in this study. The lower-limb assessment tool can also be utilized to prevent WMSDs related with lower-limbs as well as improve working environments.

• 대한인간공학회지
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• 제31권2호
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• pp.363-370
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• 2012

Objective: The objective of this study is to analyze standards of ISO 9001, ISO 14001, KOSHA 18001, GAP and ISO 22000 to make an integrated system and check whether an integrated system can be used at small size companies. Background: There are many certification criteria for quality, safety and health such as ISO 9001, ISO 14001, KOSHA 18001, GAP and ISO 22000. However, these criteria are difficult and complicated to be used at a small size company. Thus. it is not easy for small size companies to obtain certifications using these criteria. But customers and workers of small size companies want the key points of these systems to be implemented. Method: ISO 9001, ISO 14001, KOSHA 18001, GAP and ISO 22000 were analyzed to find the commonality and duplications as well as the importance of the items in these standards. And a survey was conducted to check whether certain aspects of the anticipated integrated system can be implemented at small size companies. Results: Items were classified into categories based upon the importance to food safety, quality, safety, environment, and health. Items which are common among standards were also identified and thus give ideas to make the new standards simpler than the currently available standards. Items which were important but may not be easily implemented at the small size companies were also identified. Conclusion: By considering the fact that the currently used accreditation standards have many similar aspects, these systems can be integrated into one new system which small size companies can use relatively easily.

• Journal of Biosystems Engineering
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• 제33권3호
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• pp.157-166
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• 2008

Protected horticulture is labor-intensive. It necessitates great amount of labor in many tasks including grafting, pollination and harvesting. Particularly, carrying crops involves the most intensive labor which leads to a high risk of musculoskeletal disorder. Thus, this study aims at developing an ergonomic vehicle to reduce this intensity of labor and ergonomic evaluation by applying the newly developed vehicles to REBA. 5 healthy male subjects with no records of any musculoskeletal disorder were participated in this study. The experimental units were divided into three categories: lifting, lowering and pushing tasks. The results showed that the developed vehicle received less loads in group B (arms and wrists) than in group A (trunk, neck and legs). Especially, the developed vehicle scored $1.0{\sim}4.4$ in group C on REBA while the conventional wheelbarrow got $3.0{\sim}7.6$, regardless of working postures. In conclusion, the developed ergonomic vehicle provided less loads for human bodies compared to the conventional one.

• 대한인간공학회지
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• 제34권3호
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• pp.279-291
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• 2015

Objective: The purpose of the study is to evaluate appropriate weight for aged farmers in manually handling livestock feed in bags using ergonomic methods. Background: In the livestock industry in South Korea, despite the trend of aging of labor manpower, heavy items are still manually handled in many farms. In particular, among stockbreeding works, the handling of feed in bags weighing 25~30kg is reported as a cause of frequent injuries and musculoskeletal system diseases. However, studies on the standard for recommended weight allowed considering the physical characteristics of aged farmers older than 60 years with greatly decreased physical strength and muscle strength are insufficient. Method: To evaluate appropriate weight for handling of heavy livestock feed in bags, physical techniques for measuring recognized levels of physical work loads, the NLE (NIOSH lifting equation) a method that is an observation type technique, and an ergonomic modeling technique to predict compressive force imposed on L5/S1 were used. Subjects who participated in the experiment were organized into two groups of males/females with mean age exceeding 60 years, and lifting tasks were evaluated for nine weight levels. Results: Based on the results of psychophysical measurement, females showed a tendency of more drastic increases compared to males when weight was over 19kg. The results of estimation of regression models for the weight, 18.0 kg ($r^2=0.97$) and 15.3kg ($r^2=0.97$) were evaluated as stable load for males and females, respectively. In addition, both the observation type evaluation and ergonomic model evaluation showed stable loads in a range of 15~18kg. Conclusion: Given the results of the study, the weight of the feed in bags currently distributed to farms can become a cause of not only overexertion but also farm work related disasters such as musculoskeletal disorders and safety accidents. Providing livestock feed in bags weighing not more than 19kg for aged farmers is judged desirable, and managerial improvement for this matter is considered necessary. Application: The results of the present study can be utilized as useful data for institutional improvement of the weight of livestock feed in bags.

• 대한인간공학회지
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• 제35권5호
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• pp.383-389
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• 2016

Objective: In this paper, work time for the representative fruit crops are collected and analyzed using time-diary method, and the collected data were compared with the directly observed work time using GPS device. Background: There is no consistent conclusion which measurement method for work time is accurate. Most of the research results were collected from the environment other than rural area. Therefore, there is need to review reliability of the measurement methods for the agricultural work which are carried out for a long duration. Method: Top five crops (apple, pear, grape, sweet persimmon, and peach) were selected according to the number of farms and cultivation areas. We let fruit growers fill a work diary during one cropping period. A difference between the work-time that was recorded by the farmers and the direct observed worktime using GPS device were analyzed. Results: Average direct work time for the five fruit crops found to be 7.1% of the total work time. Conclusions and Applications: Reliability was secured by recording the daily work diary at each work stage while aware that direct observation is carried on. Data which are being collected by government institutions are obtained by the memories of the respondents. Therefore, it is needed to try the method adopted by this study in order to collect more accurate data.

• 대한인간공학회지
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• 제31권6호
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• pp.773-783
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• 2012

Objective: The aim of this study is to identify foot shapes of Korean male farmers by classifying their foot types using 3D scan data and analyzing the characteristics of each type. Background: The increasing demands for anthropometric information for the design of machinery and personal protective equipment to prevent occupational injuries has necessitated an understanding of the anthropometric differences to be found among occupations. Static stooped posture and squatting posture are so common in Korean farmers that anthropometric deformation in foot especially seems to occur easily. Method: 366 Korean male farmers volunteered for this study from 16 different farming villages nationwide from 2009 to 2011. Subjects were categorized into 4 age groups from 40s to 70s. Their right feet were measured by using 3D foot scanner, the anthropometric dimensions were composed of 40 items. Results: The 8 major factors affecting the foot shapes were extracted. From these factors the foot shape of Korean male farmers was classified into 3 Foot types. Foot type 1 showed severe deformation in toe 1, type 2 had a narrow shape and type 3 had a wider width for its length. Conclusion: There were some differences in foot shape and types between farmers and the public. The most characteristic foot type in Korean male farmers was type 3. Application: The results of identifying foot shapes of Korean male farmers might provide the useful information for designing ergonomic farm work shoes.

• 대한인간공학회지
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• 제36권5호
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• pp.545-557
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• 2017

Objective: The aim of this study was to find risk factors in cultivating ginseng based on risk assessments and suggest safety measures for main risks. Background: Safety education and training is one of the practical and effective methods to prevent occupational accidents and injuries. In agricultural sector, there are few contents of safety education as compared to other industries. Especially, farm work has different cultivation characteristics according to the crops, so it needs special education materials for each crop. Among the various types of crops, ginseng contains various risk factors due to its long cultivating period and unique environment. Therefore, safety education material specified for ginseng is necessary to improve ginseng farmers' safety. Method: Risk assessment for cultivating tasks of ginseng was carried out through data obtained from various methods (site survey, interview, literature survey). To improve objectivity, the risk assessment was applied with 3-criteria (researcher estimate, interview, previous research results). Finally, the three high-risk tasks were selected and safety measures for those tasks were provided. Results: Three tasks, such as 'Mounting, maintenance and removing supports', 'Pest control' and 'Harvest', were selected as risky tasks among total tasks. (1) In 'Mounting' and maintenance and removing supports', the farmers found to be exposed to the risks of musculoskeletal disorders and accidents related to operating the tablet machine. (2) In 'Pest control', agrichemical poisoning, musculoskeletal disorders and hyperthermia were main risks. Finally, (3) In 'Harvest', the farmers are mainly exposed to the possibility of accidents of agricultural machines and risks of musculoskeletal disorders. Thus, it needs to apply appropriate safety measures to those risky tasks, such as safety guidelines, convenience equipment, protective kit, and so on. Conclusion: This study can be used as basic data for agricultural safety and expected that it would be useful for further study. In addition, the results of the research will be produced in the form of animation, which will enhance the safety consciousness for aged farmers. Application: The result of this study can be used in developing safety education materials for ginseng farmers which is essential to prevent occupational accidents and injuries among ginseng farmers.

• 대한인간공학회지
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• 제30권6호
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• pp.695-703
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• 2011

Objective: This study was to investigate the effects of coordinated upper-limb body postures on the subjective discomfort rating, heart rate, and muscle activities. Background: Although generally many checklists such as OWAS, RULA, and REBA were applied to evaluate various body postures, the body postures were might be overestimated or underestimated because each body part(i.e., back, shoulder, and elbow etc.) was evaluated separately, and then added all rates of individual body parts to assess an overall risk level for the body posture in these methodologies. Methods: A total of 20 participants maintained 14 postures which were combinations of back, shoulder, and elbow flexion angles and then muscle activities, subjective discomfort, and heart rates were collected every three minute during a sustained 15 minute and 0.5kg weight holding task. Four muscle groups were investigated: erector spine, anterior deltoid, upper trapezius, triceps brachii. Results: Results showed that subjective discomfort was the lowest when the angle of back and shoulder were both $0^{\circ}s$, while the body posture with $45^{\circ}$ of back angle and $45^{\circ}$ shoulder angle was rated as the most subjective discomfort posture. In general, the subjective discomfort ratings increased as back and shoulder flexion angles increased. It was noted that, however, the subjective discomfort of body posture with a $45^{\circ}$ back angle and $45^{\circ}$ shoulder flexion angle was lower than that of body posture with a $0^{\circ}$ back and $45^{\circ}$ shoulder flexion angle. The research findings of heart rates and muscle activities showed similar results for the analyses of subjective discomfort ratings. Conclusions: The possible limitations of the current ergonomics evaluation techniques which assessing a body posture with summing all body part score after individually analyzed in this study. Based on the analyses of subjective discomfort, heart rate, and muscle activities, it was recommended that a use of effects of coordinated upper-limb body postures would be considered when one evaluates work-load for various working postures. Application: These findings can be used for developing a more accurate assessment checklist for working posture as well as preventing musculoskeletal disorders of workers in workplaces.

• Safety and Health at Work
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• 제9권2호
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• pp.164-171
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• 2018

Background: In recent years, the interest in health and safety in the workplace has increased. Agriculture is one of the human work activities with the highest risk indexes. Studies on risk perception of agricultural workers are often referred to as specific risk factors (especially pesticides), but the risk perception plays an important role in preventing every kind of accident and occupational disease. Methods: The aim of this research is to test a new method for understanding the relation between risk perception among farmers and the main risk factors to which they are exposed. A secondary aim is to investigate the influence of training in risk perception in agriculture. The data collection was realized using a questionnaire designed to investigate the risk perception; the questionnaire was given to a sample of 119 agricultural workers in central Italy. Through the use of the "principal components analysis" it was possible to highlight and verify the latent dimensions underlying the collected data in comparison with scales of attitudes. Results: Results show that the highest percentage of strong negative attitude is among the people who have worked for more years, while farmers who have worked for fewer years have a marked positive attitude. Conclusion: The analysis of the questionnaires through the synthetic index method (Rizzi index) showed that agricultural workers involved, in particular the elderly workers, have a negative attitude towards safety; workers are hostile to safety measures if they have not attended special training courses.