• 대한인간공학회지
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• 제25권2호
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• pp.11-22
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• 2006

The muscular-skeletal disorders(MSDs) that have become a major issue recently in Korean industrial safety area are mainly caused by manual material handling task. The objective of this study is to provide scientific data for the establishment of work safety standard for Korean workers through the experiments of lifting task under various conditions, in order to prevent the muscular-skeletal disorders in the industrial work site. Eight male college students were recruited as participants. Three different lifting frequencies(1, 3, 5 lifts/min) and three twisting angles(including the sagittal plane and two asymmetric angles; i.e., 0°, 45°, 90°) for symmetric and asymmetric tasks, respectively, with three lifting range from floor to knuckle height, knuckle to shoulder, floor to shoulder height for one hour's work shift using free style lifting technique were studied. The maximum acceptable weight of load(MAWL) was determined under the different task conditions, and the oxygen consumption, heart rate, and RPE were measured or recorded while subjects were lifting their MAWLs. The results showed that: (1) The MAWLs were significantly decreased as the task frequency and task angle increased.; (2) The heart rate, oxygen consumption, RPE significantly increased with an increase in lifting frequency although maximum acceptable weight of lift decreased.; (3) The highest heart rate and oxygen consumption was recorded at the lifting range of floor to shoulder, followed by floor to knuckle and knuckle to shoulder.; (4) The RPE value showed that subjects perceived more exertion at the high frequency rate of lifting task and lifting range of floor to shoulder height. (5) The modeling for MAWL using isometric strength, task angle and lifting frequency were developed. It is expected that use of the results provided in this study may prove helpful in reducing MMH hazards, especially from lifting tasks for Korean, and can be used as a basis for pre-employment screening.

• Safety and Health at Work
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• 제7권1호
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• pp.32-37
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• 2016

Background: Previous research has shown that paramedics are exposed to risks in the form of injuries to the musculoskeletal system. In addition, there are studies showing that they are also at increased risk of cardiovascular disease, cancer, and psychiatric diseases, which can partly be explained by their constant exposure to stress. The aim of this study is to evaluate whether the use of shoulder straps decreases physical effort in the form of decreased heart rate and cortisol concentration. Methods: A stretcher with a dummy was carried by 20 participants for 400 m on two occasions, one with and one without the shoulder straps. Heart rate was monitored continuously and cortisol samples were taken at intervals of 0 minutes, 15 minutes, 30 minutes, 45 minutes, and 60 minutes. Each participant was her or his own control. Results: A significant decrease in heart rate and cortisol concentration was seen when shoulder straps were used. The median values for men (with shoulder straps) at 0 minutes was 78 bpm/21.1 nmol/L (heart rate/cortisol concentration), at 15 minutes was 85 bpm/16.9 nmol/L, and at 60 minutes was 76 bpm/15.7 nmol/L; for men without shoulder straps, these values were 78 bpm/21.9 nmol/L, 93 bpm/21.9 nmol/L, and 73 bpm/20.5 nmol/L. For women, the values were 85 bpm/23.3 nmol/L, 92 bpm/20.8 nmol/L, and 70 bpm/18.4 nmol/L and 84 bpm/32.4 nmol/L, 100 bpm/32.5 nmol/L, and 75 bpm/25.2 nmol/L, respectively. Conclusion: The use of shoulder straps decreases measurable physical stress and should therefore be implemented when heavy equipment or a stretcher needs to be carried. An easy way to ensure that staff use these or similar lifting aids is to provide them with personalized, well-adapted shoulder straps. Another better option would be to routinely sewn these straps into the staff's personal alarm jackets so they are always in place and ready to be used.

• 대한인간공학회지
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• 제29권2호
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• pp.211-216
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• 2010

Fire service personnel and ambulance paramedics suffer musculoskeletal disorders as they lift and carry patients while performing Emergency Medical Services (EMS). The objective of the current study was performed to examine the association between working environment and musculoskeletal disorders of 119 paramedics and to analysis the EMS activities for them through basic survey (including task characteristics, risk factors, symptoms and illnesses). Observational job analysis of EMS activities indicated the squatting posture during first-aid performed on floor and the abrupt use of force during carrying heavy load including stretcher with patients on as hazard factors, and excessive low back twisting and bending during stairway transfer was observed. In addition, work-physiological assessment revealed various but rather high lumbar muscle usage rate among the study subjects, being 14.6~32.8% compared with Maximum Voluntary Contraction (MVC) during patients transfer work. Resting heart rate showed 65/min, on the other hand, heart rate on mobilization indicated maximum 124~156/min. Therefore, the results of analysis to the EMS activities, rescuer activities and medical tasks were accompanied with high possibility of accident and musculoskeletal disorders. Also, EMS activities indicated high muscle fatigue and energy consumption, and accumulated muscle fatigue with during continued work.

• Safety and Health at Work
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• 제13권1호
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• pp.99-103
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• 2022

Background: Firefighters may experience high environmental temperatures or carry out intensive physical tasks, or both, which leads to increased core body temperature and risk of fatalities. Hence there is a need to remotely and non-invasively monitor core body temperature. Methods: Estimated (heart rate algorithm) and actual core body temperature (ingested telemetric pill) measures were collected simultaneously for comparison during training exercises on 44 firefighter volunteers. Results: Prediction of core body temperature varied, with no specific identifiable pattern between the algorithm values and directly measured body core temperatures. Group agreement of Lin's Concordance of 0.74 (95% Upper 0.75, lower CI 0.73), was deemed poor. Conclusion: From individual agreement data Lin's Concordance was variable (Min 0.11, CI 0.13-0.01; Max 0.83, CI 0.86-0.80), indicating that the heart rate algorithm approach was not suitable for core body temperature monitoring in this population group, especially at the higher more critical core body temperatures seen.

• 한국산림과학회지
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• 제87권2호
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• pp.121-130
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• 1998

별도작업에서 작업원의 작업강도를 파악하기 위하여, 체인톱을 이용한 낙엽송 간벌작업에서 작업시간과 작업량을 조사하였으며, 작업시 심박수의 변화를 조사하였다. 또한, 작업원의 최대 작업수행 능력을 평가하기 위하여 최대산소섭취량을 조사하였다. 1일 실작업시간은 6시간 6분으로 오전작업시간이 약 3시간 12분, 오후가 2시간 54분으로 나타났고, 전체작업시간 중 실작업시간의 약 90% 정도를 차지하는 것으로 나타났으며, 실작업시간 중 요소작업 의 시간비율은 이동(Movement)의 비율이 평균 26.3%로 가장 큰 값을 보였다. 작업원의 작업량을 분석하기 위하며 시간당 벌목재적을 조사한 결과 평균 $2.62m^3/hr$로 나타났다. 작업원의 작업능력을 평가하기 위하여 최대산소섭취량을 분석한 결과, 평균 $2.42{\ell}/min$($46.5m{\ell}/kg/min$)으로 나타났으며, 작업시 심박수를 바탕으로 체인톱을 이용한 낙엽송 간벌작업 중 실동시간의 작업강도를 분석한 결과, 실동시간의 심박수 증가율은 평균 93.2%로 나타났고, 작업강도지수는 평균41.9%로 나타났다.

• 감성과학
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• 제9권1호
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• pp.1-7
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• 2006

본 연구의 목적은 21%농도의 산소와 비교하여 30%의 고농도 산소 흡입이 사이클 등속 운동 중에 심박동률(heart rate)과 혈중 산소 포화도($SPO_2$)에 미치는 영향을 분석하는 것이다. 21%와 30% 농도의 산소를 각각 8liter/min의 양으로 일정하게 공급할 수 있는 산소 공급 장치를 이용하였다. 신체 건강한 10명의 남자 대학생($25.2{\pm}2.2$세)이 21%와 30%의 두 종류의 산소 농도를 대상으로 각각 두 번의 실험에 참여하였다. 실험은 안정(2분), $20{\pm}1km/h$의 사이클 등속 운동(10분), 회복(6분)의 세 구간(총 18분)으로 구성되어 있고, 21%또는 30%의 산소는 등속 운동과 회복 구간에만 공급되었다. 21%에 비해 30%산소를 흡입했을 때 사이클 등속 운동과 회복 기간 중에 심박동률은 감소하였고, 혈중 산소 포화도는 .차이가 없었다. 21%와 30% 두 그룹 사이에 동일한 운동부하가 주어졌기 때문에 혈중 산소 포화도는 차이가 없는 것으로 판단되고, 30%의 고농도 산소 흡입으로 동일운동 부하에 필요한 산소 요구량이 원활히 공급되고 있기 때문에 심박동률은 감소한 것으로 판단된다.

• 감성과학
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• 제4권1호
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• pp.1-5
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• 2001

The evaluation of mental workload is measured by subjective ratings, physiological signals. It takes long time to analysis the measured signals and is very tedious and time-consumming work. Therefore, to evaluate the affect of workload effectively, real-time measurement system is required. In this paper, real-time mental workload measurement system using cardiac autonomic indiced which reflect well the mental workload was developed and evaluated. Analyzed indices were HR, IBI, Lorentz plot, CSI, CVI, and LF/HF ratio of heart rate variability. The system was applied to evaluate the affect of arithmetic task and showed good results. This system was consisted of ECG amplifier, A/D converter, and personal computer, and algorithm was implemented using LabVIEW.

• 한국농촌생활과학회지
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• 제7권2호
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• pp.121-128
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• 1996

This study was performed to define the effects of Far Infrared Ray Radiation Fabrics as summer garments during outdoor work by human trial. One healthy male subject was volunteered for this study. Experimental garments consisted of three kinds of trousers (Cotton, Cotton/linen blended, Far Infrared Ray Radiation Fabric/wool blended) and basic garments (panty, socks, shirts, and dress shirts). The measurements were rectal temp., skin temp., microclimate inside clothing, heart rate, subjective sensation etc. The results were as follows : 1. Rectal temperature showed the lowest in Far Infrared Ray Radiation Fabrics among 3 garments. 2. Skin temperature (forehead, chest abdomen temp.) and mean skin temperature were lower in Far Infrared Ray Radiation Fabrics than in others, especially during early stage of work. 3. Heart rate showed lower value in Far Infrared Ray Radiation Fabrics than in others but there was no significance among the garments. 4. Humidity inside clothing and total weight loss showed the highest value in Far Infrared Ray Radiation Fabrics.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.55-56
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• 2018

In order to reduce the risk of accidents, we proposed a construction safety management system combined with wearable device and LoRa (Low-Range Wireless Network) communication method to apply the usefulness of Internet (IoT) technology which means "everything connected". to construction safety management Management system. The proposed wearable safety device is a device that relays information exchange between wearable safety device and safety management server by LoRa wireless communication method. The safety management server can store workers bio-data and perform big data analysis. If a risk factor is determined from the analysis result, a warning is sent to the wearable safety device and the manager's application. The goal of this system is to prevent construction workers from entering the dangerous area that is not suitable for work, and to prevent safety accidents caused by human cause by detecting abnormal condition during work.

• 대한물리치료과학회지
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• 제11권4호
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• pp.20-28
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• 2004

The studys purpose were the effects of work posture, treatment method and prevention for Video Display Terminal(VDT) workers in Work-Related Musculoskeletal Disorders(WMSD) The results were as follows: 1. The prevalence rate of VDT workers in WMSD was $20{\sim}40%$. The complaint was mostly shoulder, neck, and hack area pain 2. VDT worker used to forward flexed posture and then affect of increase of muscle fatigue and pain 3. When exercise therapy PT and ADL training, were used workers decrease in pain, muscle strength, balance training, endurance strength and relief of psychiatricIn conclusion, VDT worker need good health and posture to rest and exercise with time space and treatment. It is best to prevent WMSD. VDT workers need health management by itself and systemic rehabilitation program by speciality therapist.