• Title/Summary/Keyword: exposure standards

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Comparative Analysis of Exposure to Hazardous Factors of Welding Lab Activities in Specialized High School (특성화 고등학교 용접 실습의 유해인자 노출 실태 비교 분석)

  • Min-Ju Kim;Seong-Eun Jang;Hwa-Il Kim
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.34 no.2
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    • pp.156-165
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    • 2024
  • Objectives: This study aims to identify and analyze the exposure status of welding students in specialized high school welding labratories, compare it with the exposure to welding hazards of industrial workers, and seek to improve the educational environment for youth through domestic and international exposure standards. Methods: This study compares the level of exposure to hazardous factors in a welding laboratory of a vocational high school in Jeollanam-do and a welding process in a general industrial site by measuring the work environment. A 10-question survey was conducted to review the effects of welding hazards on the human body, carcinogenicity information, international (US, UK, France) exposure standards, general characteristics between the two groups, and awareness of occupational health. Results: Exposure to hazardous factors in both groups was below the standards set by MOEL. Specialized high school students were exposed to higher levels than workers, and some hazardous factors exceeded the standards when compared to international exposure standards. During the survey, students were less aware of the hazards of welding, safety and health education, and the need for work environment measurement than workers. Conclusions: For the respiratory protection of students in vocational high school welding labs, it is necessary to create a comfortable training environment. Exposure standards for harmful factors should be strictly applied, such as overseas standards, or exposure should be limited by setting a limit on the number of hours of welding practice per week. In addition, it is necessary to conduct safety and health education for welding students to raise their awareness of the importance of measuring the working environment and wearing appropriate protective equipment.

Effects of Long-term Exposure of High and Low Humidity on Thin-film Humidity Sensors

  • Lee, Sang-Wook;Choi, Byung Il;Kim, Jong Chul;Woo, Sang-Bong
    • Journal of Sensor Science and Technology
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    • v.27 no.6
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    • pp.368-373
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    • 2018
  • The effects of long-term exposure of high and low humidity on thin-film humidity sensors are investigated. Five commercially available thin-film humidity sensors are initially calibrated in a humidity chamber as a reference before longterm exposure to high and low humidity. Then, the sensors are kept in a high-humidity environment (~95 %rh) for four months. After the exposure, the sensors are calibrated in the same manner as the initial calibration. Consequently, the device reading values from the humidity sensors are elevated up to about 5 %rh. Interestingly, the degree of elevation by the high-humidity exposure shows a negative correlation with the price of the humidity sensors. Humidity sensors are then kept in a low-humidity environment (~10 %rh) for another four months. After the exposure, a calibration similar to the initial calibration is performed. As a result, the device reading from humidity sensors is decreased, indicating a recovery from the effect of high-humidity exposure. The durability test conducted in this study provides experimental evidence for the use of thin-film humidity sensors in high-humidity environments such as greenhouses and food factories for a long period of time.

Derivation of Soil Fluorine Standards Based on a Human Health Risk Assessment Method (위해성 평가 기법에 따른 토양 불소 기준안 연구)

  • Seung-Woo Jeong
    • Journal of Soil and Groundwater Environment
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    • v.29 no.3
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    • pp.14-22
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    • 2024
  • This study established risk-based fluoride soil contamination standards according to the Korean Soil Contaminant Risk Assessment Guidelines (SRAG). Ten exposure scenarios were evaluated, broadly categorized into Scenario 1, which used the default parameters from the current SRAG, and Scenario 2, which used the latest exposure factors and bio-concentration factors. Fluoride soil standards corresponding to a total hazard index (HI) of 1.0 were determined for each scenario. For children in agricultural areas, the derived risk-based soil fluoride standard was 70 mg/kg for Scenario 1 and 27 mg/kg for Scenario 2. In industrial areas, the risk-based fluoride soil standard was 2200 mg/kg in Scenario 1 and 2300 mg/kg in Scenario 2. This study clearly demonstrated that the crop ingestion exposure pathway exerted predominent influence on the estimated human health risk standards. Additionally, using the Added Risk Approach and considering soil background concentrations, the total fluoride soil standards for residential areas ranged from 232 mg/kg to 444 mg/kg, while the standards for industrial areas ranged from 2405 mg/kg to 2674 mg/kg.

A Review on the Vibration Exposure Limits in Korea

  • Park, Hee Sok
    • Journal of the Ergonomics Society of Korea
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    • v.34 no.3
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    • pp.217-222
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    • 2015
  • Objective:The objective of this study is to review the exposure limits in the legislation, guidelines, and standards for human vibration in Korea. Background: There have been relatively less interests in vibration than other risk factors in Korea. However, the importance of vibration is increasing as industry and everyday life are more mechanized. Method: Various enforcements were examined including legislation, guidelines, and standards for whole-body vibration and localized vibration. Results: No exposure limits were found in legislation, guidelines, and standards for the human vibration in Korea. Conclusion: It is important to introduce new duties regarding vibration risks to the general duties. Further studies are expected on the vibration exposure limits appropriate for Korean people and job conditions. Application: The results from this study would be of help to induce more interests in human vibration to the occupational health and safety professionals of Korea.

Study on Radiation Dose in the Medical Image Data Display Method - Focused on the DICOM Standard (의료영상 데이터에서의 피폭선량 표시 방법에 관한 고찰: DICOM 표준을 중심으로)

  • Kim, Jung-Su
    • Journal of radiological science and technology
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    • v.38 no.4
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    • pp.483-489
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    • 2015
  • DICOM (Digital Imaging and Communications in Medicine) standards are generally introduced as de facto and de jure standards in modern medical imaging devices to store and to transmit medical image information. DICOM Dose Structured Report (DICOM dose SR) is implemented to report radiation exposure information in image acquiring process. and DIOCM Modality Performed Procedure Step (DICOM MPPS) is also partly used to report this exposure with the information in its DICOM tag. This article is focused on three type of radiation exposure information of DICOM standards, 1) DICOM dose SR, 2) DICOM MPPS and 3) Radiation Exposure Monitoring(REM) profile by Integrating the Healthcare Enterprise(IHE), to study on radiation exposure reporting. Healthcare facility and its staff of medical imaging related to radiation exposure should have a deep understanding of radiation exposure, and it required a standards to enhance the quality control of medical imaging and the safety of patients and staffs. Staff member have to pay attention on radiation exposures and controling processes from the purchasing stage of X-ray devices.

Ultrafine Particle Toxicities, Current Measurement Techniques and Controls (Ultrafine Particle의 독성, 측정방법 및 관리)

  • Lee, Su-Gil;Kim, Seong-Soo
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.20 no.3
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    • pp.203-215
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    • 2010
  • This study is an overview of toxicities and measurement techniques of ultrafine particles (UFPs), and their exposure controls. UFPs are ubiquitous in many working situations. Exposure to UFPs is possibly causing adverse health symptoms including cardio-respiratory disease to humans. In order to measure exposure levels of airborne UFPs, there are current available measurement guidelines, instruments and other techniques (i.e. contour mapping, control banding). However, these risk assessment techniques including measurement techniques, controls and guidelines are dependent on background levels, metrics (e.g. size, mass, number, surface area, composition), environmental conditions and controls. There are no standardized measurement methods available and no generic and specific occupational exposure standards for UFPs. It is thought that there needs to be more effort to develop Regulations and Exposure Standards for generic UFPs should be based on more exposure data, health surveys, toxicological data and epidemiological data. A carefully considered hierarchy of controls can also reduce the maximum amount of airborne UFPs being emitted from diverse sources in industries.

Exposure Measurements of Co-60 Gamma rays (Co-60 감마선의 조사선량 측정)

  • Hah, Suck-Ho;Kim, Hyun-Moon
    • Journal of Radiation Protection and Research
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    • v.16 no.2
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    • pp.7-16
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    • 1991
  • Measurement of Co-60 gamma rays has been made for establishment of exposure standard and analyze it's overall uncertainties. Exposure rate determined by the charge mode method using vibrating reed amplifier with cylinderical type cavity chamber. The values of a variety of physical constants and the correction factors are evaluated. The resulting exposure rate is 690.81 R/h at the distance of 1m from the source and the related uncertainties is ${\pm}0.8%$

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Experimental Investigations on Barrier Oxidation in $N_{B}/A_{L}O_{X}/N_{B}$ Josephson Junctions

  • Kim, Kyu-Tae;Hong, Hyun-Kwon;Lee, Sang-Hwa;Nam, Du-Woo;Lee, Kyu-Won
    • Progress in Superconductivity and Cryogenics
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    • v.5 no.1
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    • pp.17-20
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    • 2003
  • Josephson junctions were fabricated for several oxidation conditions and several junction sizes. Considering self-field effect suppressing the observed critical current (Ic) at large junctions, the observed Ic values were in good agreement with theoretical prediction. The predicted junction critical current for small junction limit was also confirmed by experiment. The dependence of the estimated Jc as a function of oxidation exposure showed that our junctions have lower Jc than other authors' at the same oxidation exposure. This is thought to be one of equipment-specific phenomena. Details of experimentals will be reported with brief discussion.

A Study on the Corrosion Properties of Reinforcing bar and Performance Evaluation of Repair Material and Method for Reinforced Concrete Structure by Exposure Experiment under the Coastal and Normal Atmosphere Environment (해양 및 일반대기환경의 폭로실험에 의한 철근콘크리트구조물 보수재료.공법의 성능평가 및 철근의 부식특성에 관한 연구)

  • Nam Jeong-Soo;Roh Kyung-Min;Shin Seung-Bong;Kim Young-Sun;kim Gyu-Yong;Kim Moo-Han
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.05a
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    • pp.167-171
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    • 2006
  • In this study, for the establishment of the performance evaluation methods of repair material and method for reinforced concrete structure and the quality control standards of durability recovery method, the quantitative exposure data by exposure experiment under the coastal and normal atmosphere environment is accumulated and analyzed. Investigating and evaluating the result of exposure experiment during 30 months of exposure age under the coastal and normal atmosphere environment, carbonation depth and chlorideion penetration depth very little penetrated than cover depth. It seems reasonable to conclude that main cause of corrosion of reinforcing bar are inner chloride-ion and macro cell from the result of corrosion area and corrosion velocity. Accordingly, it is considered that fundamental data on the performance evaluation and quality control standards of repair material and method could be presented through continuous exposure test in the future.

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Standard Trends of Human Exposure to Electromagnetic Waves (전자파 인체 노출 표준 동향)

  • Jeon, S.B.
    • Electronics and Telecommunications Trends
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    • v.34 no.3
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    • pp.86-92
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    • 2019
  • New products and services, such as 5G and wireless power transmission equipment, have recently brought about changes in the field of electromagnetic technology. There is a need for the evaluation and measurement of the health effects of such technology. To address this need, the development of international standards related to human exposure to electromagnetic waves of these new technologies are currently being discussed. This article briefly introduces the International Standard Organization standards for human exposure to electromagnetic waves, and focuses on the major standard trends for SAR measurement techniques that employ vector probes, wireless power transfer, and 5G base station measurement.