• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.3
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• pp.155-165
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• 2010

In low-lying districts of urban areas, pump stations were built to protect flooding by the heavy rain. Particularly, the automatic pump operation system was installed for efficiency in the pump stations of Seoul. However, the effective pump operation is difficult under existing operating system because the system only performs operation by reservoir depth. This study would like to improve the real time operating system suggested by Jun et al.(2007) and to apply the system Gasan 1 pump station in Seoul. For various design rainfall events, maximum water levels simulated by the suggested system were 10~70cm lower than results by the existing system. And overflow volume at upstream manholes were 50% reduced. We converted the flood control effects by establishment of the suggested system to economic indicators. To obtain the same effect, approximately 4.9 billion won needs to expand pump capacities or 3.2~6.9 hundreds million won needs to construct storm water detention on upstream area. The suggested system could improve the flood control stability by efficient operation of the existing pump station.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.6
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• pp.349-356
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• 2015

Trace metals concentrations in the tissue of edible marine fish (4 species), olive flounder (Paralichthys olivaceus), Korean rockfish (Sebastes schlegelii), file fish (Stephanolepis cirrhifer) and abbysal searobin (Lepidotrigla abyssalis), collected near the Yongho wharf in Busan were determined to assess the potential human health risk (HRA) of trace metals by fish consumption. Levels of Li, Cr, Ni, Cu, Zn, As, Cd, and Pb in the fish tissue were $0.005{\pm}0.009$, $0.77{\pm}0.30$, $0.29{\pm}0.34$, $0.49{\pm}0.14$, $15.96{\pm}2.52$, $10.62{\pm}4.67$, $0.001{\pm}0.002$, and $0.045{\pm}0.06mg/kgdw$ respectively. The estimated daily intakes of Cu and Zn and the estimated weekly intakes of As, Cd, and Pb from the fish collected near the Yongho wharf were 0.0032, 0.054-0.18% of PMTDI (provisional maximum tolerable daily intake) and 13, 0.0041, 0.020% of PTWI (provisional tolerable weekly intake) which were set to evaluate the food safeties by the JFCFA (The Joint FAO/WHO Expert Committee on Food Additives). Lifetime cancer risk and target hazard for local residents due to those fish consumption were found to be negligible.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.210-214
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• 2009

This study identified microbial risk factors in agricultural products processing center (APC) through the microbial hazard analysis to introduce good agricultural practices (GAP) system in APCs. Samples were collected from surroundings (basket, tray loader, weighing cup, collector, box) and workers by swabbing (glove and cloth) and glove juice method (hand) to enumerate total bacteria, coliform, Staphylococcus aureus, Escherichia coli, Escherichia coli O157:H7 and Salmonella. The levels of total bacterial and coliform populations recovered from surroundings were 2.4-5.7 log CFU/100 $cm^2$ and 2.3-5.7 log CFU/100 $cm^2$ or hand for surroundings, and workers, respectively samples were 2.3-5.7 log CFU/100 $cm^2$ or hand. Escherichia coli populations were determined to be below detection limit. S. aureus and Salmonella populations recovered from surroundings were 3.0-4.4 log CFU/100 $cm^2$ and close to detection limit, respectively. Corresponding bacterial populations to worker's samples were 2.8-5.2 log CFU/100 $cm^2$ or hand (S. aureus) and below detection limit (Salmonella). Bacterial populations of APC certified facilities were similar (p${\geq}$0.05) with those of uncertified facilities. These results showed that this study should be useful in development of GAP models to improve microbial safety in APCs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.211-216
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• 2010

On 7 December 2007, about 12,547 kL of crude oil spilled from the Hong Kong registered tanker Hebei Spirit along the west coast of the Republic of Korea, including Taean-gun, Chungcheongnamdo Province. This study evaluated the safety of seafood collected from the coastal area polluted by the crude oil. The range of total polycyclic aromatic hydrocarbons (${\sum}PAHs$) at 22 stations was 3.9-37.1 ng/g. The concentration of ${\sum}PAHs$ was higher in oysters, Crassoatrea gias, than that in short-necked clams, Ruditapes philippinarum. Benzo(a)pyrene, a highly toxic PAH, ranged from 0.07-1.47 ng/g, which did not exceed the European Union regulatory limit for benzo(a)pyrene. The toxicity equivalent of benzo(a)pyrene in oysters and short-necked clams was 0.49-1.70 and 0.09-1.01 ng/g, respectively. The estimated life time cancer risk was very low, i.e., $1.31{\times}10^{-8}$ for the oysters and $6.9{\times}10^{-9}$ for the short-necked clams. The body burden of PAHs in bivalves originated mostly from petroleum contamination, but the levels was not sufficiently high to harm human health.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.287-293
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• 2005

Microbial contamination levels in commercial strawberry juices were examined for sanitary indication bacteria, such as aerobic plate count (APC), coliforms, and Escherchia coli, and pathogenic bacteria such as E. coli O157:H7, Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes. APC and coliform count ranged 0-5.2 and $0-2.8\;log_{10}\;CFU/(mL,\;g,\;100cm^{2},\;hand)$, respectively, and 80% strawberry juices were contaminated with E. coli and S. aureus, detected at 19%, was found in employee's hands, strawberries, and strawberry juices, whereas E. coli O157:H7, Salmonella spp, and L. monocytogenes were not detected. These results will provide microbiological information for introduction of Hazard Analysis Critical Control Point (HACCP) system in juice shops.

• Journal of the Mineralogical Society of Korea
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• v.28 no.4
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• pp.309-323
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• 2015

This study was initiated to propose the method for human risk assessment suitable to metal mine area. Using a variety of exposure parameters extracted from the investigation of abandoned metal mines, the proposed method was applied to assess the risk of As and heavy metal contamination for inhabitants (male and female adults and child) within an abandoned mine area. Based on the results of risk assessment, in addition, target remediation concentrations of each media (soil, groundwater, and surface water) were estimated. The results indicate that total carcinogenic risk (TCR) and hazard index (HI) representing carcinogenic and non-carcinogenic risks, respectively, were calculated to exceed the tolerable levels (1.00E-6 and 1) with regard to two exposure pathways (groundwater and crop intakes) and As. Thus, the human risk of study area was evaluated to be significant. Based on the target risk (TR) for carcinogens, the remediation concentrations of soil were computed to be 6.83~6.85 mg/kg and 18.41~18.46 mg/kg for As and Pb, respectively. In terms of target hazard index (THI) for non-carcinogens, the remediation concentrations of soil were calculated to be 17.38 mg/kg for Cu and 9.13 mg/kg for As.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.1
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• pp.107-113
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• 2009

This study has been conducted for the long-term riverbed change prediction on Geum River and Miho Stream surrounding the planned Multifunctional Administrative City and the neighboring regions by the construction of a small dam. Based on the analysis of vertical riverbed changes of the cross-sectional data for the years 1988, 2002 and 2007, minimum bed elevation significantly decreased in both Geum River and Miho Stream in 2007 as compared to 1988. Compared to 2002, however, a slight elevation change was observed. To make a long-term prediction on riverbed changes by the construction of a small dam, a one dimensional HEC-RAS 4.0 model has been used. By the fixed bed model test, the water levels were calibrated. By using the cross-sectional data of 1988 and 2002, verification was conducted under a movable bed model. According to the prediction of riverbed changes for each scenario with varying height of small dam, minor impact is expected around Miho Stream while major impact is expected around Geum River by 2017, as the small dam height increases. If the small dam is 7m-high, for example, it's been simulated that 1.59m deposition would be expected around the upper stream of Miho Stream Confluence while 1.98m scour would be expected around the downstream of the small dam.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.298-309
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• 2019

Objectives: This study aimed to investigate stages of safety and health culture change through a reflection on 40 years of hearing conservation history at a multinational company. Methods: The target workplaces were multinational companies with more than 1,000 employees. The research used the clinical case study and system analysis methods based on direct observation of the research from 1994 to 2009. The latter method performed an analysis of the equilibrium state of the cross-section in the given period and the longitudinal profile of the change during the given period. Results: The stages of cultural change are divided into five stages and summarized as follows. In the first stage, workplace noise was not widely recognized as a hazard, while in the second stage, the measurement of noise levels and audiometric testing were conducted under the Korean Occupational Safety and Health Act (KOSHA). The driving force for change in the second stage was the amendment of the KOSHA. In the third stage, noise came to be recognized as a hazard factor through awareness training. The driving force of change during the third stage was the strong executive power exerted by the audit of the industrial hygiene program from the US head office. In the fourth step, there was a change to actually reduce noise. The driving force in this stage was a change in company executives' risk perception resulting from lawsuits over noise-induced hearing loss and the task force team activities for culture change based on the action learning protocol. At the fifth stage, a 'buy quiet policy' was institutionalized. The management's experience that noise reduction was difficult was the motivation to manage noise from the time of purchase of equipment. Conclusions: The activities of a hearing conservation program are determined by the improvement of the legal system and by the way it is enforced. Noise control activities to reduce noise areas may be possible through the shared risk perception of noise-induced hearing loss and by a change agent role as a facilitator to implement noise control.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.83-89
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• 2011

A series of full-scale testing was conducted to examine the effect of stairwell pressurization on the pressure differential between the stairwell and the auxiliary room and between the auxiliary room and the residence. Also, flow velocity profiles at open doors were measured. The building tested was a condominium that had twenty floors above the ground and two floors underground. For pressurization of the stairs, a blower was used to supply air into the stairwell at one location underground. Thirteen different cases were tested, and test variables included the number of floors with open doors and the flow rate of the air supply. When the doors on the first floor were open, the pressure differential between the stairwell and the auxiliary room was distributed almost uniformly except for locations near the first floor. When the flow rate was in the range of 180~270 CMM and the doors of one floor were open, the flow velocity could satisfy the requirement of fire safety standards and the stairwell pressure was positive at all levels. However, the minimum pressure requirement (10 Pa) could not always be satisfied. When doors on two floors were open, the flow velocity requirement could be satisfied by increasing the flow rate, but it was found impractical to satisfy the minimum pressure requirement without causing excessive pressure differential in the area near the blower.

• Journal of Environmental Impact Assessment
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• v.30 no.6
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• pp.380-392
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• 2021

An indoor air quality index for school classrooms based on the Hazard Quotient (HQ) was developed in this study. The current index (IAQI-S) covered PM₁₀, PM_2.5, and CO₂, and breakpoints of IAQI-S were calculated using each HQ value. IAQI-S was applied to the real-time data obtained from 123 classrooms of 46 schools during November 2017 to December 2020. As a result of the comprehensive assessment, 93.1% of PM₁₀ and 94% of PM_2.5 belonged to 'good' and 'moderate', respectively. The IAQI-S based on an 8-hour predicted moving average was compared with Comprehensive Air-quality Index (CAI) and with the IAQI of a foreign reference. The IAQI-S includes CO₂ and consists of more stringent levels comparing to outdoor index (CAI).