Economical Ventilation Effectiveness to Reduce Hazardous Chemical Emissions for a Nail-Salon Worker

권우택,정민재,이우식,Lee-Seung Kwon,소영진 한국유통과학회 2019 유통과학연구 Vol.17 No.7

Purpose – The purpose of this study is to investigate economical ventilation effectiveness to reduce hazardous materials exposure and damage of workers by analyzing exposure amount of noxious substances under various ventilation conditions of nail salon for indoor environments. Research design, data, and methodology – This study was carried out with cooperation of Nail shop located in SeongNam city to involve an analysis of the environmental impact indoor air quality, pollutant exposure and economical cost-effectiveness in the nail workplace. The hazardous substances were PM-10(Particulate Matter-10㎛), VOCs(Volatile Organic Compounds) and Formaldehyde, which are the major materials of nail workplace. Results – PM-10 is reduced by about 60% with air cleaner, forced artificial ventilation by 32%, and natural ventilation by about 12%. TVOCs and Formaldehyde showed similar efficiency (80~100%) after natural ventilation and ventilation after 60 minutes. The removal efficiencies of VOCs and formaldehyde were similar to those of natural ventilation and mechanical ventilation system. However, in case of dust, natural ventilation was reduced by artificial ventilation system due to inflow of external dust during natural ventilation. Conclusions – If the pollution degree of outdoor air is not high, air volume is high, and natural ventilation is performed when the air conditioning and heating system is not operated. Even at the end of the work, it keeps operating for 60 minutes to remove the pollutants generated. Results of this analysis demonstrated that the worker environment can be improved by adopting institutional legislation and guidelines for ventilation.

Comparison of volume flow rate and volume-averaged local mean age of air for evaluating ventilation performance in natural ventilation

박진수,이광훈 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.12

Evaluating the ventilation performance is an important part of natural ventilation studies. We considered the volume flow rate, which is used by many researchers, and the volume-averaged Local mean age of air (LMA) as the ventilation performance parameters to evaluate the performance of natural ventilation. Computational fluid dynamics (CFD) simulations were performed on an isolated building model of cross ventilation that contained two openings on the windward and leeward wall and single-sided ventilation model that consisted of a single opening. Parametric studies were performed to evaluate the ventilation performance of eight different building configurations in cross ventilation and single-sided ventilation. Using the volume flow rate it was difficult to evaluate the ventilation performance when the inlet and outlet were very close in cross ventilation and, in single-sided ventilation, it was difficult to evaluate when the airflow speed was fast near the opening but did not penetrate inside the building. While the volume-averaged LMA was an adequate parameter for representing the ventilation performance of the building, the LMA field was a more accurate representation of the local ventilation performance inside the building than the velocity vector field.

Optimal Method to Ventilate Hazardous Substances Generated in Indoor Space

Woo-Taeg KWON,Min-Jae JUNG,Woo-Sik LEE,Lee-Seung KWON,Young-Jin SO 한국유통과학회 2018 KODISA ICBE (International Conference on Business Vol.2018 No.-

This study aims to investigate the ventilation method to reduce the hazardous substance exposure of workers by analyzing the exposure amount of noxious substances depending on the nail shop ventilation conditions. Research design, data, and methodology - This study was carried out with cooperation of Nail shop located in SeongNam city to study indoor air quality and pollutant exposure environment of workers in nail work space. The research subjects were PM-10(Particulate Matter-10㎛), VOCs and Formaldehyde, which are the major materials of nail work space. PM-10 appeared in the order of air purifiers (about 60% reduction) > ventilation (about 32% reduction)> natural ventilation (about 12% reduction). TVOCs showed similar efficiencies (85~99%) after natural ventilation and ventilation after 60 minutes. Formaldehyde showed similar efficiency (80~100%) after natural ventilation and ventilation after 60 minutes. The removal efficiencies of VOCs and formaldehyde were similar to those of natural ventilation and mechanical ventilation system. However, in case of dust, natural ventilation was reduced by artificial ventilation system due to inflow of external dust during natural ventilation. If the pollution degree of outdoor air is not high, air volume is high, and natural ventilation is performed when the air conditioning and heating system is not operated. Even at the end of the work, it keeps operating for 60 minutes to remove the pollutants generated. If institutional legislation is introduced and guidelines for ventilation are provided, it is likely that the worker exposure environment can be improved.

지하철 환기구 재설계를 통한 보행자 편의성향상 연구

김시준,김정수,김정태 한국기계기술학회 2018 한국기계기술학회지 Vol.20 No.1

The subway is a common transportation system accessed by over 8 million people on a daily basis in Metropolitan Seoul area. The subway ventilation system located on a street occupies a large area of walkways which cause inconvenience to the public. In this paper, approaches to reduce the ventilation sitting area on the pathway are examined. 5 different preliminary models of ventilation systems are analyzed to minimize the pathway obstacle area such that the public may have an easy access to pass by on the street. The amount ofthe air ventilation is predicted using the CFD software to ensure an efficient ventilation. The ventilation performance is verified by theory and numerical analysis. The result shows that one of the proposed model combined with the hybrid ventilation satisfies the regulation requirement of the air quantities. We may conclude that the proposed ventilation design provides a smooth walking environment to the public while the ventilation volume is maintained to the existing ventilation system with no modification of the current ventilation holes and structures.

Automatic ventilation control algorithm considering the indoor environmental quality factors and occupant ventilation behavior using a logistic regression model

Kim, Hakpyeong,Hong, Taehoon,Kim, Jimin Elsevier 2019 Building and environment Vol.153 No.-

<P><B>Abstract</B></P> <P>Building occupants find it difficult to achieve the optimal indoor environment quality (IEQ) through natural ventilation. To solve this problem, this study aimed to develop an automatic ventilation control algorithm considering the IEQ factors and occupant ventilation behavior. The algorithm was developed in four steps: (i) real-time collection of data on the IEQ factors and occupant ventilation behavior; (ii) development of the automatic ventilation control algorithm using logistic regression; (iii) determination of the automatic ventilation control algorithm using receiver operating characteristic curve analysis; and (iv) evaluation of the automatic ventilation control algorithm's performance according to the indoor environmental standards. Through this process, the logistic regression model with ridge regression (area under curve: 0.865), with the highest classification accuracy, was selected. Then Youden's index was used to define the decision criterion (i.e., optimal cutoff value) for the logistic regression model. As a result, the decision criterion for opening and closing the windows or doors was 0.533. When the developed algorithm was compared with the indoor environmental standards to analyze its performance, the compliance rate of the opening of the windows or doors based on the monitored data was 77.6%, but it increased to 99% based on the data classified by the developed algorithm. It is expected that if the automatic ventilation control algorithm is embedded in a building ventilation system, which is connected to various IEQ measurement sensors, it will offer a customized building ventilation system to the building occupants.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Occupant ventilation behavior was influenced by indoor environment quality factors. </LI> <LI> CO<SUB>2</SUB> concentration was the most influential driver for occupant ventilation behavior. </LI> <LI> Developed algorithm was applied to classify opening and closing of the windows/doors. </LI> <LI> Developed algorithm could manage IEQ considering regression coefficient. </LI> <LI> Developed algorithm could provide a new decision boundary for customized comfort zone. </LI> </UL> </P>

실내공기질을 고려한 공동주택의 하이브리드 환기시스템의 성능평가

이용준,이승복,이경회,원종서 대한건축학회 2005 대한건축학회논문집 Vol.21 No.9

The purpose of this paper was to evaluate the possible control modes of hybrid ventilation system in applying to general apartments. It evaluates range of hybrid ventilation control modes in terms of indoor air quality, thermal comfort, and energy consumption in 85.8㎡(net area) apartment. The TRNSYS simulation program was used for evaluating the following four ventilation types: 1) a ventilation mode relying on only infiltration for supplying air(S1), 2) a natural ventilation mode considering with weather condition(S2), 3) a hybrid ventilation<natural+mechanical ventilation> mode allowing minimum ventilation with no heat exchange(H1), 4) a hybrid ventilation mode with heat exchange(H2). This study shows the following results. As temperature being controlled by heating & cooling equipments, there is without significant difference in thermal performance among ventilation types. Regarding IAQ(Indoor Air Quality), Indoor air contamination level of the hybrid ventilation case consistently keep the lower levels. The hybrid ventilation modes consume more energy by a 49% as compared to the a ventilation mode relying on only infiltration for supplying air. It is caused by the continuous ventilation for keeping good indoor air quality; the increase of energy consumption can be attributable to the increase of the heating energy. Therefore, the heat exchange between indoor and outdoor air is required during heating season in severe weather conditions. During the cooling seasons, Introducing natural ventilation can achieve energy saving by 40~45%. Based on these results, a hybrid ventilation system can be suggested as an effective ventilation strategy for archiving high level of indoor air quality, thermal comfort, and energy consumption.

신생아 호흡곤란 증후군에서 volume-controlled ventilation과 pressure-limited ventilation의 효과에 관한 비교연구

김재진,황문종,이상길 대한소아청소년과학회 2010 Clinical and Experimental Pediatrics (CEP) Vol.53 No.1

Purpose:In contrast with traditional time-cycled, pressure-limited ventilation, during volume-controlled ventilation, a nearly constant tidal volume is delivered with reducing volutrauma and the episodes of hypoxemia. The aim of this study was to compare the efficacy of pressure-regulated, volume controlled ventilation (PRVC) to Synchronized intermittent mandatory ventilation (SIMV) in VLBW infants with respiratory distress syndrome (RDS). Methods : 34 very low birth weight (VLBW) infants who had RDS were randomized to receive either PRVC or SIMV with surfactant administration : PRVC group (n=14) and SIMV group (n=20). We compared peak inspiratory pressure (PIP), duration of mechanical ventilation, and complications associated with ventilation, respectively with medical records. Results:There were no statistical differences in clinical characteristics between the groups. After surfactant administration, PIP was significantly lower during PRVC ventilation for 48hrs and accumulatevive value of decreased PIP was higher during PRVC ventilation for 24hrs (P<0.05). Duration of ventilation and incidence of complications was no significant difference. Conclusion:PRVC is the mode in which the smallest level of PIP required to deliver the preset tidal volume in VLBW infants with RDS, adaptively responding to compliance change in lung after surfactant replacement. 목적:인공호흡기 사용과 관련된 폐손상에 대한 연구가 활발히 이루어져 왔다. 특히 전통적 압력조절방식의 인공호흡기 사용시 발생하는 용적손상의 중요성이 밝혀지면서 신생아 호흡 곤란 증후군의 치료에서 용적조절방식의 인공호흡기가 부각되고 있다. 이에 저자들은 신생아 호흡곤란 증후군 환아를 대상으로 전통적 압력조절방식의 SIMV와 용적조절방식을 바탕으로 한 PRVC를 비교분석하고자 하였다. 방법:2007년 5월부터 2008년 4월까지 대구파티마병원 신생아 중환자실에 입원한 환아중 출생 체중이 1,500 g 미만이고 신생아 호흡곤란 증후군이 있어 기도삽관에 의한 인공호흡기 치료 및 폐표면 활성제를 투여한 환아 34명을 대상으로 하여 PRVC 사용군 14명, SIMV 사용군 20명으로 나누어 비교하였다. 폐표면 활성제 투여 후 시간경과에 따른 PIP값의 변화, 감압된 PIP의 누적값, 기도발관까지의 기간, 그리고 전체 인공호흡기 사용기간을 조사하였고, 주요 합병증인 폐외 공기 누출, 기관지폐 이형성증, 폐고혈압, 미숙아 망막증, 뇌실내 출혈, 동맥관 개존증의 빈도를 조사하였다. 결과:재태연령, 출생시 체중, 성별, 극소 저출생 체중아 비율, 1분 및 5분 Apgar 점수, 호흡 곤란 증후군 등급, 폐표면 활성제 투여 횟수 및 분만 방법, 산모의 임신성 고혈압, 조기양막파수 유무에서 두 군간의 임상적 특성 차이는 없었다. 폐표면 활성제 투여 전 및 투여 후 48시간까지의 PIP값은 PRVC군에서 보다 낮게 측정되었고, 투여 후 24시간까지 PRVC군에서 PIP의 감압이 더 잘 이루어 졌다(P<0.05). 기도발관까지 걸린 시간과 전체 인공호흡기 사용기간, 합병증의 발생 빈도 및 퇴원시점까지 소요된 시간 비교에서는 의미있는 차이는 없었다. 결론:SIMV군에 비해 PRVC군에서 PIP 값이 낮고, 폐표면 활성제 투여 후 감압이 더 잘 이루어졌다. 급변하는 폐유순도에 상응하는 감압에 있어 PRVC군이 더 유리하다고 볼 수 있다. 호흡기 이탈기간 및 합병증의 발생에 있어 차이는 없었으나, 잠재적인 폐의 용적손상과 관련 기존 SIMV군에서 필요 이상의 PIP가 설정되었던 것으로 생각되는 바, 이는 앞으로 더 많은 연구가 필요할 것으로 사료된다.

Performance evaluation of CO₂-based ventilation control to reduce CO₂ concentration and condensation risk in residential buildings

Shin, Mi-Su,Rhee, Kyu-Nam,Lee, Eun-Tack,Jung, Gun-Joo Elsevier 2018 Building and environment Vol.142 No.-

<P><B>Abstract</B></P> <P>As the airtightness of a building envelope gets higher to achieve energy efficiency, the necessity of appropriate ventilation for residential buildings is continually increasing. Many residential buildings are equipped with energy recovery ventilators (ERV) for energy-efficient ventilation; however, the ERVs are usually operated by occupants' manual control, which often leads to insufficient or unnecessary ventilation. Because it is difficult to operate an ERV during nighttime, when occupants cannot control the system, a residential building can suffer from poor indoor air quality and increasing condensation risks. Herein, a CO<SUB>2</SUB>-based ventilation control strategy was implemented in an existing ERV system for residential buildings. Considering that most ERV systems operate with a central control, the appropriate CO<SUB>2</SUB> sensor location (or representative room) was investigated in a mock-up residential building. Comparative experiments were conducted to evaluate the control performances in terms of indoor air quality (CO<SUB>2</SUB> control performance) and fan energy consumption. Experimental results showed that a living-room-based control can maintain an overall CO<SUB>2</SUB> concentration in the entire space at acceptable levels. It was also shown that a living-room-based control resulted in reduced ventilation energy if the CO<SUB>2</SUB> dispersed through open bedroom doors. The CO<SUB>2</SUB>-based ventilation control was modified to mitigate the condensation risk while minimizing the possibility of fan noise or cold draught. Through mock-up experiments on a modified CO<SUB>2</SUB>-based ventilation control, it was shown that CO<SUB>2</SUB> concentrations can be maintained at acceptable levels and condensation risks can be mitigated even when the outdoor temperature decreases to −15 °C.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Field measurement results showed the necessity of CO<SUB>2</SUB>-based ventilation control for residential buildings. </LI> <LI> CO<SUB>2</SUB>-based ventilation control was implemented to the existing energy recovery ventilator. </LI> <LI> Living-room-based ventilation control was effective in maintaining overall CO<SUB>2</SUB> concentration at acceptable levels. </LI> <LI> CO<SUB>2</SUB> dispersion through the bedroom doors could reduce the fan energy consumption. </LI> <LI> CO<SUB>2</SUB>-based ventilation control could prevent window condensation caused by occupants' respiration. </LI> </UL> </P>

공동주택 거주자들의 창문개방행위에 따른 연간 자연환기량 분포와 환기부하에 관한 연구

유지현,박준석 한국건축친환경설비학회 2022 한국건축친환경설비학회 논문집 Vol.16 No.3

Recently, due to sick house syndrome, the importance of indoor air quality is emerging. The method of managing the indoor air quality includes mechanical ventilation and natural ventilation. However, the majority of occupants prefer using natural ventilation rather than mechanical ventilation and even don’t know the existence of mandatory mechanical ventilation in residential building. Therefore, recent studies have focused on natural ventilation, which can easily manage the indoor air quality, and propose a ventilation guideline by developing a ventilation module due to the opening of the window. However, hot and cold outdoor air through the window opening affects the indoor temperature, which in turn has a big impact on energy consumption. Previous studies researched the window opening behavior (opening frequency and hours) with outdoor factors and found that the outdoor temperature had the greatest effect on window opening behavior. However, with this only window opening behavior, we couldn’t predict the precise energy consumption and couldn’t purpose the natural ventilation guideline because we don’t know the accurate volume of the outdoor air comes into the building. Therefore, in this study, field measurement is conducted for 4 complexes and 30 samples. we analyze the window opening behavior as same as previous study and the ventilation rates through carbon dioxide decay method. As a result, the measurement period could represent the outdoor temperature of korea. However, despite that outdoor temperature was similar, the distribution of indoor temperature was different by all the samples, especially in heating period. The window opening behavior and ventilation rates have correlation with outdoor temperature. The ventilation load was low in heating period, because of the lack of ventilation behavior. In contrast, the ventilation load in cooling period was greater than that in heating period. .

백-밸브-마스크 보조장치를 이용한 환기효과 비교

서은영,윤병길,김가은,김용석 사단법인 한국응급구조학회 2022 한국응급구조학회지 Vol.26 No.3

Purpose: TThe experiment was designed to compare the efficiency of ventilation between conventional BVM ventilation and a newly devised A-BVM ventilation method with Tidal volume, total ventilation rate, average Ventilation speed, and average Ventilation volume. Methods: 40 Paramedical students who agreed to participate in the study were analyzed. Values were measured using IMB PASS after 2 minutes of Bryiden Pro manikin with BVM and A-BVM ventilation. The difference in general characteristics was assessed by t-test and ANOVA and the difference in ventilation methods was analyzed by IBM SPSS. Results: A significant difference was found between the two ventilation methods in terms of tidal volume (t=-11.203, p<.001), ventilation time (t=-3.834, p<.001), and optimum ventilation probability (t=10.770, p<.001). A-BVM ventilation method, rather than BVM ventilation method, showed a value close to the appropriate amount recommended by Korean Advanced Life Support (500~600mL) in tidal volume, and higher in optimum ventilation probability. Conclusion: We could identify the a better mode of ventilation. Further studies on the efficacy of existing BVM ventilation methods as compared to device augmented BVM ventilation methods should be carried out to ensure that adequate ventilation is available to patients in clinical practice.