• Journal of Microbiology and Biotechnology
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• 제31권7호
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• pp.956-966
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• 2021

To prevent the outbreak of infectious diseases that inflict huge economic and social losses, domestic livestock farms and related facilities have introduced automatic and semiautomatic disinfectant solution-spraying systems for vehicles. However, the facility standards and specifications vary by manufacturer, and no scientific performance evaluation has been conducted. The puropose of this study is to develop physical and biological evaluation methods. Physical and biological appraisals were conducted using two types of disinfection facilities (tunnel- and U-type) and two types of vehicles (passenger car, truck). Water-sensitive paper was used to evaluate the physical performance values for the disinfection facilities. In addition, to assess their biological performance, carriers containing low-pathogenic avian influenza virus were attached to vehicles, and the viral reduction was measured after the vehicles moved through the facility. The tunnel-type had rates of coverage in the range of 70-90% for the passenger car and 60-90% for the truck. At least 4-log virus reduction after spraying for 1-5 min was shown for both vehicles. For the U-type facility evaluation, the coverage rates were in the range of 60-90% for the passenger car and at least 90% for the truck. More than 4-log viral reduction was estimated within a spraying time of 5 min. To reduce viruses on the surface of vehicles by at least 4 log within a short period, the disinfectant solution should cover at least 71% of the pathogens. In conclusion, we were able to assess the physical and biological performance criteria for disinfection facilities aboard transportation vehicles.

• 한국물환경학회지
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• 제18권3호
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• pp.327-336
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• 2002

Disinfection process in water treatment plants (WTPs) is one of the most important step in order to inactivate waterborne disease. However, what is the necessary disinfection in WTPs was not properly established in Korea. This study was conducted to evaluate disinfection performance in nationwide water treatment plants (n=474). Disinfection requirement based on the SWTR (Surface Water Treatment Rule) of the U.S. (1-log Giardia removal) was chosen in estimating the compliance. The scope of unit process for evaluating disinfection performance includes postdisinfection process in clearwells, pipeline, and storage tank. The worst water quality condition in individual WTPs was applied for the disinfection performance evaluation. The major results are as follows. First, it was appeared that 184 WTPs (39 %) provided insufficient disinfection performance. Disinfection performance was significantly improved during past 2 years. The ratio of the number of WTPs providing insufficient disinfection performance in 1999 and 2001 was 78 % and 41 %, respectively. One of major factors for this improvement was due to the improvement of $T_{10}/T$ value in clearwell, as a result of modification of clearwell facility. Second, if disinfection criteria is 3-log Giardia inactivation at worst water quality condition, then 19 % of all WTPs can not meet this disinfection criteria. And if disinfection criteria is strengthened to 4-log Giardia inactivation, then 58 % of all WTPs can not meet this disinfection criteria. Since disinfection criteria is decided by contamination level of Giardia in source water, it also needs the investigation of Giardia occurrence in source water.

• Journal of Microbiology and Biotechnology
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• 제12권4호
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• pp.699-701
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• 2002

The current study demonstrates the ability of the marine cyanobacterium Oscillatoria willei BDU130511 to disinfect raw sewage. Within a holding time of 3 h under laboratory conditions, the organism drastically reduced in the total bacterial and coliform counts at various pH levels, in both unbuffered and buffered sewage, thereby suggesting a potential role for cyanobacteria in wastewater treatment.

• 인터넷정보학회논문지
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• 제22권6호
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• pp.41-49
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• 2021

Due to the COVID-19 pandemic, issues related to quarantine are emerging. There are various infection prevention methods, but among them, it is certain to frequently disinfect the surface or the entire space of an object that has come into contact with the virus. However, the reality is that the number of times such disinfection is legally designated and the required number of personnel are very different depending on the building and facility. For this reason, there are no companies and systems that can professionally receive orders for disinfection work. In order to solve the aforementioned problems, this paper presents a method to design a disinfection service platform based on the MVC pattern, and implements the required functions based on this. Through this, it is possible to build a more systematic system, and it is hoped that it will be of great help to quarantine with an orderly process for disinfection work.

• 상하수도학회지
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• 제30권5호
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• pp.587-596
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• 2016

This study attempts to draw factors for an analysis of the operation effect of a rechlorination facility and autodrain equipment for residual chlorine equalization by installing and operating a rechlorination facility and autodrain equipment in P City and analyzing the practical evaluation method and operation effect. For this purpose, this study selected three indicators for an analysis of the effectiveness of residual chlorine equalization and conducted a comparative analysis before and after the implementation of the residual chlorine equalization. As a result of estimation, (1) the reduction of the residual chlorine concentration range from a water treatment plant to the pipe end was 16.0%; (2) the total reduction of chlorination input was 18.0%; and (3) the reduction of the generation of disinfection by-products was 19.5%. In addition, this achieved enough residual chlorine equalization in the supply process and shows that it could successfully achieve the economic feasibility of investment in equipment and the reduction of the generation of disinfection by-products. Like this, it is judged that the three indicators suggested in this study will be used sufficiently as indicators of an analysis of the effectiveness of residual chlorine equalization according to the operations of the rechlorination facility and autodrain equipment.

• 급식외식위생학회지
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• 제2권2호
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• pp.103-110
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• 2021

This study was conducted to compare and evaluate the difference in washing and disinfection when the Hazard Analysis and Critical Control Point (HACCP) protocol was applied to foodservice operations. The results of the survey were as follows: Among the 116 foodservice operations surveyed, 67.2% were HACCP-compliant and 32.8% were not HACCP-compliant. Also, 62.9% served meals once daily, and 79.3% conducted food safety education once a month. Compared to HACCP non-compliant foodservice operations, the disinfection performance of HACCP-compliant operations was significantly better concerning worktables (p<0.001), food inspection tables (p<0.001), preparation tables for distribution (p<0.01), serving tables (p<0.01), overflow and trenches(p<0.05), sinks (p<0.05), and insect attracting lamps (p<0.01). Similarly, the disinfection performance of HACCP-compliant foodservice operations was significantly better for 18 cooking utensils and personal tools such as food slicers (p<0.001), multiple cooking machines (p<0.05), tray carts (p<0.001), stainless steel tools (p<0.001), rubber gloves (p<0.05). Worktables (45.1%), serving tables (29.6%), sinks (37.0%), and scales (21.6%) were most often disinfected 'at the end of each task', while food inspection tables (36.5%), food preparation tables for distribution (31.2%), dish machines (34.2%), overflow and trenches (25.7%), and floors (25.8%) were most often disinfected 'once a day'. All cooking utensils were most often disinfected 'at the end of each task'. 'Chemical disinfection' was most frequently used in all foodservice facilities. To improve the food safety management of foodservice operations, it is necessary to apply the HACCP protocol and comply with the washing and disinfection manual.

• 상하수도학회지
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• 제19권3호
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• pp.330-337
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• 2005

This study was carried out to propose the managemental improvement of the purification plants and the distribution facilities which can minimize the formation of disinfection by-products in drinking water distribution system. The disinfection by-products were highly created in the water treatment plant that the organic matters were high and the chlorine dosage was excessive. The concentration of DSPs was shown the highest value in August and the lowest value in December, because of temperature and pre-chlorine dosage effect. From the result of tracer test, the travel time from the treatment plant to the end of pipeline was around 3-4 days in summer, 5-6 days in winter, respectively, and the DSPs concentration of the reservoir(end of pipe) was 2-3 times higher than that of the beginning point. The improvement of the chlorination process and structural reformation of distribution facility was demanded to minimize the DSPs increase from purification plant to the end of pipe.

• 한국산학기술학회논문지
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• 제12권8호
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• pp.3644-3653
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• 2011

본 연구는 수처리 주요공정의 소독공정에 대한 자동운전 구축현황과 목표주입율 결정시 체류시간동안 염소 소모량을 분석하고 활용하기 위한 기술을 연구하고 제시하는데 있다. 본 연구를 위하여 자동운전을 위한 시설물 구조 및 하부설비 설치현황을 조사하였으며, 현 시스템의 문제점을 분석하고 해결을 위한 자동운전 프로그램을 개발하여 적용하였으며 이에 따른 효과도 분석 제시하였다. 특히 시지연공정 및 다변수 공정제어에 적합한 모델예측제어 알고리즘을 적용하여 환경인자와 반응시간 등의 상관관계를 분석하고 최적 제어 입력값을 추론할 수 있도록 함으로써 안정적인 공정제어가 가능함을 모델평가를 통하여 확인하였다.

• 디지털융복합연구
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• 제16권5호
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• pp.299-307
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• 2018

본 연구는 치과의료기관의 감염관리실태의 규명과 감염예방을 위해 대구, 경북지역 2012년, 2017년 2개 년도 동일한 114개의 치과의료기관의 특성에 따른 감염관리실태와 오폐수처리 및 기구소독을 설문조사하였다. 감염관리실태 8문항 평균 3.37이며 '환자의 질병병력 기록'은 95.5%로 높고 '오폐수시설이 있는 경우' 1.8%로 낮았다. 오폐수처리 및 기구소독의 9항목 평균 4.87이며 '메탈트레이 소독' 94.7%로 높고, '타구통 폐기물을 폐기물통에 보관 후 위탁처리' 17.5%, '로 낮았다. 일반적인 특징과 치과의료기관 특성에 따른 감염관리실태와 오폐수처리 및 기구소독은 2012년보다 2017년이 높았으며, 치과위생사, 대학졸업이상, 환자상담 및 관리, 병원급 이상, 치과의사 수(치과위생사 수, 체어 수, 환자 수)는 많은 경우 높았다. 총괄적으로 치과 특성을 고려하여 감염관리를 하여야 할 것이며 병원규모와 관계없이 지속적인 교육과 홍보를 필요할 것으로 사료된다.

• 한국식품영양과학회지
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• 제33권10호
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• pp.1653-1660
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• 2004

부산시내 초등학교 5곳을 방문하여 현 급식소에서 보유하고 있는 급식시설$.$설비에 대한HACCP 적용시 중점관리점을 파악하기 위하여 위생평가를 실시하였다. 학교 급식 시설$.$설비는 학교급식소에서 사용하고 있는 천장, 벽, 바닥, 트렌치, 그리스 트랩, 후드, 방충망, 덤웨이터 등 총 8곳으로 분류하여 총균수, 대장균군수 측정을 통해 위생상태를 확인하였다. 급식시설$.$설비 표면의 위생상태를 검사한 결과 천장, 벽을 제외한 나머지에서 $10^4$∼$10^{6}$ CFU/100 $\textrm{cm}^2$의 세균이 검출되어 여전히 학교급식소의 위생수준이 낮은 것으로 파악되었고 특히, 그리스 트랩의 경우가 가장 위생상태가 불량한 것으로 나타났다. 대장균군수의 경우는 천장을 제외한 나머지 장소에서 $10^2$∼$10^4$ CFU/100 $\textrm{cm}^2$의 세균이 검출되었고 그리스 트랩에서 가장 높은 수의 세균과 대장균이 발견되어 특별히 관리 해야 되는 부분으로 확인되었다. 또한 학교급식 시설$.$설비의 하절기 및 동절기의 위생상태를 알아보고 중점 관리 점을 제시하기 위하여 급식 후 세 척 및 소독을 실시한 다음 시간 및 요일의 경과에 따른 오염도를 측정한 결과, 하절기에는 매일 소독을 실시해야 하는 바닥, 트렌치, 그리스 트랩, 덤웨이터의 경우는 급식 전에 소독을 실시한 후 급식을 시작해야 하는 것으로 나타났고, 주 1회 소독을 실시 하는 벽, 후드, 방충망은 주 3회 이상으로 소독횟수를 늘려 실시해야 하는 것으로 나타났다. 동절기에는 바닥, 트렌치, 덤웨이터의 경우는 현재와 마찬가지로 급식 후에 소독을 실시하여야 하는 것으로 나타났고 그리스 트랩의 경우는 급식 전에 실시한 후 급식을 시작해야 하는 것으로 나타났다. 벽, 후드, 방충망은 주 2회 이상으로 소독횟수를 늘려 실시해야 하는 것으로 나타났다.