• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5B
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• pp.489-499
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• 2006

The Potential Flood Damage (PFD) is widely used for representing the degree of potential of flood damage. However, this cannot be related with the design frequency of river basin and so we have difficulty in the use of water resources field. Therefore, in this study, the concept of Potential Risk for Flood Damage Occurrence (PRFD) was introduced and estimated, which can be related to the design frequency. The PRFD has three important elements of hazard, exposure, and vulnerability. The hazard means a probability of occurrence of flood event, the exposure represents the degree that the property is exposed in the flood hazard, and the vulnerability represents the degree of weakness of the measures for flood prevention. Those elements were devided into some sub-elements. The hazard is explained by the frequency based rainfall, the exposure has two sub-elements which are population density and official land price, and the vulnerability has two sub-elements which are undevelopedness index and ability of flood defence. Each sub-elements are estimated and the estimated values are rearranged in the range of 0 to 100. The Analytic Hierarchy Process (AHP) is also applied to determine weighting coefficients in the equation of PRFD. The PRFD for the Anyang river basin and the design frequency are estimated by using the maximum rainfall. The existing design frequency for Anyang river basin is in the range of 50 to 200. And the design frequency estimation result of PRFD of this study is in the range of 110 to 130. Therefore, the developed method for the estimation of PRFD and the design frequency for the administrative districts are used and the method for the watershed and the river channel are to be applied in the future study.

• Wind and Structures
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• v.23 no.5
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• pp.449-464
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• 2016

Catastrophe models appraise the natural risk of the built-infrastructure simulating the interaction of its exposure and vulnerability with a hazard. Because of unique configurations and reduced number, mid/high-rise buildings present singular challenges to the assessment of their damage vulnerability. This paper presents a novel approach to estimate the vulnerability of mid/high-rise buildings (MHB) which is used in the Florida Public Hurricane Loss Model, a catastrophe model developed for the state of Florida. The MHB vulnerability approach considers the wind pressure hazard exerted over the building's height as well as accompanying rain. The approach assesses separately the damages caused by wind, debris impact, and water intrusion on building models discretized into typical apartment units. Hurricane-induced water intrusion is predicted combining the estimates of impinging rain with breach and pre-existing building defect size estimates. Damage is aggregated apartment-by-apartment and story-by-story, and accounts for vertical water propagation. The approach enables the vulnerability modeling of regular and complex building geometries in the Florida exposure and elsewhere.

• Journal of Environmental Impact Assessment
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• v.19 no.3
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• pp.259-270
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• 2010

We conducted human risk assessment for exposure to inhalation of chemical substances emitted from the storage tanks of petroleum refineries. To assess human risk, this study calculated chemical emissions from the external floating roofs on storage tank at petroleum refineries, as well as concentrations thereof in the ambient air using the K-SCREEN model, and then determined risk in accordance with the Reference Concentration (RfC) values and Inhalation Unit Risk criteria developed by the US Environmental Protection Agency. The results indicated that non-carcinogenic chemicals have a hazard quotient of less than 1, meaning they have an insignificant effect on human health for residential areas near the storage tanks. Among the known carcinogens, the hazard risk for benzene slightly exceeded $10^{-6}$, indicating the need for corrective reduction measures. The methodology for health impact assessment devised herein provides findings useful in decision making for policy makers and the general public with respect to construction of industrial complexes. However, the methodology proposed herein does have limitations, including discrepancy in results induced by use of U.S. data (due to the lack of usable domestic data). More systematic studies from related researchers will be needed to address these issues and produce more reliable outcomes.

• Safety and Health at Work
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• v.10 no.4
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• pp.428-436
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• 2019

Background: Metalworking fluids (MWFs) are mixtures with inhalation exposures as mists, dusts, and vapors, and dermal exposure in the dispersed and bulk liquid phase. A quantitative risk assessment was performed for exposure to MWF and respiratory disease. Methods: Risks associated with MWF were derived from published studies and NIOSH Health Hazard Evaluations, and lifetime risks were calculated. The outcomes analyzed included adult onset asthma, hypersensitivity pneumonitis, pulmonary function impairment, and reported symptoms. Incidence rates were compiled or estimated, and annual proportional loss of respiratory capacity was derived from cross-sectional assessments. Results: A strong healthy worker survivor effect was present. New-onset asthma and hypersensitivity pneumonitis, at 0.1 mg/㎥ MWF under continuous outbreak conditions, had a lifetime risk of 45%; if the associated microbiological conditions occur with only 5% prevalence, then the lifetime risk would be about 3%. At 0.1 mg/㎥, the estimate of excess lifetime risk of attributable pulmonary impairment was 0.25%, which may have been underestimated by a factor of 5 or more by a strong healthy worker survivor effect. The symptom prevalence associated with respiratory impairment at 0.1 mg/㎥ MWF was estimated to be 5% (published studies) and 21% (Health Hazard Evaluations). Conclusion: Significant risks of impairment and chronic disease occurred at 0.1 mg/㎥ for MWFs in use mostly before 2000. Evolving MWFs contain new ingredients with uncharacterized long-term hazards.

• Korean Journal of Occupational Health Nursing
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• v.29 no.1
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• pp.58-68
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• 2020

Purpose: Workers with chronic health problems find it difficult to maintain their work because of socioeconomic difficulties. The purpose of this study was to evaluate the relationships between physical, ergonomic, and mental health hazards in the workplace and chronic health problems of Korean workers. Methods: A total of 28,807 wage workers participated in the study and were selected using the Fifth Korean Working Conditions Survey (2017). Multiple logistic regression analysis was used to determine the associations between physical, ergonomic, and mental health hazards and chronic health problems. Results: Of the participants, 1,220 (4.23%) had chronic health problems. Even after adjusting the general characteristics, vibration, noise, high temperature, low temperature, dust, chemical and cigarette smoke, fatigue and painful posture, dragging or pushing or moving of heavy objects, repetitive hand or arm movements, working with a computer or smartphone, use of internet or e-mail, and anxiety situations increased the risk of chronic health problems. Conclusion: The study reaffirms that exposure of physical, ergonomic, and mental health hazards in the workplace significantly increases the risk of chronic health problems.

• Fire Science and Engineering
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• v.32 no.5
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• pp.22-33
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• 2018

The amount of halogen clean fire extinguishing agents has been increased by the excellent features of extinguishing, adaptability and no residue. On the other hand in situations without a hazard assessment and safety standard of agents, chemical accidents by the agents occurs frequently. This study was performed to propose the halogen clean agents' regulatory exposure limit and safety standard including the quantitative ventilation system with gas leak monitoring, hazard recognition and optimal personal protection selection through a literature review and experimental research.

• Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.66-75
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• 2024

Heavy metals are naturally found in the ecosystem, and their presence in the freshwater river is increasing through anthropogenic activities which pose a threat to living beings. In this study, heavy metal concentrations (Zn, Mn, Cu, Cd, Cu, Cr, Pb, and Ni) in different organs (muscle, skin, and gill) of fish from the Padma River were evaluated to quantify, and compare the contamination levels and related human health risks. The results revealed that the heavy metal concentrations in the water, surface sediments, and fish taken from the Padma River were far below the WHO/USEPA's permitted limits. The estimated daily intake (EDI) value in muscle was less than the tolerable daily intake (TDI). The target hazard quotient (THQ) and hazard indexes (HI) were less than 1, showing that consumers face no non-carcinogenic risk (CR). CR values of Cu, Cd, Cr, Pb, and Ni ranged from 4.00 × 10^-8 to 6.35 × 10^-6, less than 10^-4, and total carcinogenic risk (CRt) values ranged from 9.85 × 10^-6 to 1.10 × 10^-5, indicating some pose a CR from consumption of those fish from the Padma River. To establish a more accurate risk assessment, numerous exposure routes, including inhalation and cutaneous exposure, should be explored.

• The Journal of the Korean dental association
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• v.54 no.2
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• pp.155-162
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• 2016

Radiographs can help in the diagnosis and treatment planning, but the exposure to ionizing radiation may elevate the risk of developing cancer in a person's lifetime. The objective of this review is to briefly summarize 1) radiation risk, especially cancer risks associated with diagnostic imaging, 2) linear, non-threshold (LNT) hypothesis, 3) the risks of radiation exposure to a fetus, and 4) the campaign of Image Gently. The individual risk of radiation-related cancer from any single medical imaging procedure is extremely small and it is not likely to be cancer risk at doses lower than 100 mGy, but patients may be harmed by avoiding diagnostic imaging due to fear of radiation hazard. Dentists need to understand the radiation doses delivered by various radiographic techniques and the acceptable exposure thresholds to effectively advise the patient and to reduce the unnecessary radiation

• Journal of Korean Society of Industrial and Systems Engineering
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• v.13 no.21
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• pp.29-41
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• 1990

An assessment of risk in industrial and urban environments is essential in the prevention of accident and in the analysis of situations which are hazardous to public health and safety. The risk imposed by a particular hazard increases with the likelihood of occurence of the event, the exposure and the possible consequence of that event. In a traditional approach, the calculation of a quantitative value of risk is usually based on an assignment of numerical values of each of the risk factors. Then the product of the values of likelihood, exposure and consequences called risk score is derived. However vagueness and imprecision in mathematical quantification of risk are equated with fuzziness rather than randomness. In this paper, a fuzzy set theoretic approach to risk analysis is proposed as an alternative to the techniques currently used in the area of systems safety. Then the concept of risk evaluation using linguistic representation of the likelihood, exposure and consequences is introduced. A risk assessment model using approximate reasoning technique based on fuzzy logic is presented to drive fuzzy values of risk and numerical example for risk analysis is also presented to illustrate the results.

• Journal of Preventive Medicine and Public Health
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• v.37 no.4
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• pp.300-305
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• 2004

Objectives : The exposure to particulate air pollution during the pregnancy has reported to result in adverse pregnancy outcome such as low birth weight, preterm birth, still birth, and intrauterine growth retardation (IUGR). We aim to assess whether prenatal exposure of particulate matter less than 10 (m in diameter ($PM_{10}$) is associated with preterm birth in Seoul, South Korea. Methods : We included 382,100 women who delivered a singleton at 25-42 weeks of gestation between 1998 and 2000. We calculated the average PM10 exposures for each trimester period and month of pregnancy, from the first to the ninth months, based on the birth date and gestational age. We used three different models to evaluate the effect of air pollution on preterm birth; the logistic regression model, the generalized additive logistic regression model, and the proportional hazard model. Results : The monthly analysis using logistic regression model suggested that the risks of preterm birth increase with PM10 exposure between the sixth and ninth months of pregnancy and the highest risk was observed in the seventh month (adjusted odds ratio=1.07, 95% CI=1.01-1.14). We also found the similar results using generalized additive model. In the proportional hazard model, the adjusted odds ratio for preterm births due to PM10 exposure of third trimester was 1.04 (95% CI=0.96-1.13) and PM10 exposure between the seventh month and ninth months of pregnancy was associated with the preterm births. Conclusions : We found that there were consistent results when we applied the three different models. These findings suggest that air pollution exposure during the third trimester pregnancy has an adverse effect on preterm birth in South Korea.