This study evaluated changes in volatile organic compounds (VOCs) and aerosol particle concentrations following the use of certain spray-type household chemical products in an indoor environment. Four commercially available products in South Korea (including sticker/tar removers, a razor cleaner, and a fabric stain remover) were analyzed using real-time VOC monitoring with proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS) and particle number concentration measurement with an Optical Particle Sizer. Immediately after spraying 17 grams of each product, VOC concentrations increased sharply, and hazardous substances such as benzene, 1,3-butadiene, formaldehyde, and acrolein remained at elevated levels for a certain period. Additionally, some products exhibited benzene concentrations exceeding levels of potential exposure concern, and the operation of an air purifier reduced VOC levels by 73%. This research provides insight into changes in indoor air quality and associated exposure risks due to household chemical use, and it may serve as a basis for future air quality management and regulatory standards.

In this study, the initial operation characteristics of a multi-type cooling system with three indoor units using an inverter compressor were investigated experimentally using a calorimeter. The operating characteristics of the cooling system were confirmed under the full load condition of simultaneous operation of three rooms and the partial load condition of individual operation of two or one room under the standard cooling conditions. The capacities of A, B and C are 50, 20, and 30% of the total capacity, respectively. The 3 room combination has 100% capacity, the 2 room combination has 50, 70 and 80% capacity, and the 1 room has 20, 30, and 50% capacity. The compressor condensing and evaporating pressures, the electronic expansion valve openings of indoor units A, B, and C, and the compressor operating frequencies were measured for 10 minutes after the cooling system was started. During the initial operation, the changes in the operating time and opening of the electronic expansion valve varied depending on the indoor unit combination and the operating load, and the relationship between the compressor pressure and the operating frequency was found.

This study analyzed IoT-based indoor air quality monitoring data in a cooking room at a high school in Seoul. As a result of measuring the type and concentration change of cooking fumes generated during roasting, frying, and stir-fry, each cooking method showed a different pattern. Some cooking fumes were observed high during the distribution process, not during cooking, and it is necessary to observe and control indoor air quality during the entire process of cooking, storage, and distribution as well as various elements of cooking fumes. Through these results, we propose the addition of an IoT-based real-time indoor air quality monitoring system and ventilation facilities linked to it.

The importance of indoor air quality has significantly increased after the COVID-19 pandemic. This study analyzed the energy consumption of a ventilation system based on various operating methods considering indoor and outdoor conditions. From March to May 2024, experiments were conducted on ventilation systems installed in a hospital in Incheon, comparing the experimental and control groups. The results showed that using the bypass mode in the experimental group reduced total energy consumption by 25.34% compared to the control group. Additionally, utilizing the air-cleaner mode further reduced energy use. This study demonstrates that optimal use of bypass and air-cleaner modes can enhance energy efficiency. Further research is needed to verify long-term applicability under diverse conditions.

The Indoor Air Quality Control Act aims to regulate indoor air quality (IAQ) to safeguard public health and promote a comfortable living environment. This law encompasses multi-use facilities, newly constructed residential complexes, and public transportation vehicles. The law also involves mandating air quality standards, conducting periodic measurements, and transparent public reporting of results. Over time, the Indoor Air Quality Control Act has expanded to enforce stricter controls on building materials and enhance radon mitigation measures. In doing so, it embodies the principles of the Environmental Policy Basic Act and is supported by other laws, policies, and systems related to air quality management. In line with these efforts, local governments have been implementing IAQ initiatives tailored to regional needs, including consulting services and financial support. However, challenges persist in harmonizing management across diverse facilities due to overlapping responsibilities among laws and government bodies. Future recommendations emphasize integrated strategies and enhanced inter-agency coordination to address these gaps effectively, ensuring healthier indoor environments for all stakeholders.

This study presents an integrated indoor air quality index (IAQI) algorithm aimed at enhancing the efficiency of indoor air quality management in diverse indoor environments. The proposed IAQI accounts for the combined effects of multiple pollutants, offering a more comprehensive approach than traditional concentrationbased methods. Findings from four exposure scenarios and probabilistic health risk assessments indicate that the IAQI can be tailored to reflect occupant characteristics and space usage, thereby providing improved protection for sensitive populations, such as newborns. The application of occupant-specific criteria led to reductions in pollutant concentrations and associated health risks compared to conventional standards. Furthermore, the IAQI incorporates correction factors and weighted adjustments, facilitating robust risk assessments in complex multi-pollutant contexts. By addressing the limitations of single-pollutant management, this approach supports the development of more effective strategies for indoor air quality control. The proposed algorithm holds significant potential for practical applications in indoor air quality management and policymaking. Future research should focus on validating its effectiveness across a wider range of indoor environments.

This study aims to prepare bamboo-based activated carbons with surface modifications, focusing on carbon dioxide (CO2) capture in public indoor spaces. The surface of the activated carbon adsorbents was chemically modified through three steps: carbonization, steam activation, and chemical treatment using potassium hydroxide (KOH) and potassium sulfamate (KSO3NH2). The specific surface area and pore volume of the obtained adsorbent (BSAC-KN) were 1,246 m2/g and 0.74 cm3/g, respectively. The surface modification resulted in an adsorption capacity of up to 3.79 mmol-CO2/ g-AC for carbon dioxide. In addition, the expansion of the specific surface area and the enhanced physico-chemical interaction between the weak acidic CO2 molecules and the basic AC surface improved adsorption capacity.

Indoor air quality is a critical factor affecting health and quality of life, especially in spaces frequently used by sensitive populations such as adolescents. This study assessed the impact of garden ball installations and electrochemical fertilizer applications on indoor air quality in two youth centers, Center S and Center W, located in Bucheon, South Korea. PM2.5, PM10, and CO2 concentrations were monitored and analyzed based on the presence of garden balls and the use of electrochemical fertilizers. The results showed that spaces with garden balls (w/ G.B.) had significantly lower PM2.5 and PM10 concentrations compared to offices and spaces without garden balls (w/o G.B.). In Center W, the presence of garden balls alone improved air quality, highlighting the potential of vertical greening as a sustainable solution. In Center S, the application of electrochemical fertilizers during the “after + period” (when both garden balls and electrochemical fertilizers were applied) further enhanced particulate matter reduction, demonstrating the fertilizers’ ability to amplify plants’ air-purifying effects. This study provides empirical evidence that garden balls are an eco-friendly option for indoor air quality management. Combining electrochemical fertilizers with garden balls shows promise for enhancing air quality, offering a practical model for multi-use facilities such as youth centers.

Mold caused by indoor temperature and humidity is related to inflammatory reactions such as rhinitis, asthma, and allergic skin diseases. The subjects were children aged 3-7 in Seocheon-gun, Chungcheongnam-do. For indoor environmental measurement, a mold collection medium was installed on the sampling device and samples were collected at 28.3 L/min for 7 minutes. The sampling device was installed at a height of 1.2 m to 1.5 m above the ground to collect samples. The demographic characteristics of the children in the 90 households that participated in the survey were 53 males (58.9%) and 37 females (41.1%). The majority of the children were 5 years old (26 people or 28.9%), followed by 6 year olds (23 people or 25.6%), 7 year olds (18 people or 20.0%), 4 year olds (18 people or 20.0%), and 8 year olds (5 people or 5.6%). Among the characteristics listed on the questionnaire, 11 children (12.2%) were diagnosed with asthma, and 63 subjects (70%) had not been diagnosed by a doctor in the past 12 months. Regarding symptoms exhibited by the parents, 4 fathers (4.5%) and 2 mothers (2.2%) had symptoms. In the relationship between asthma and the concentration of other indoor environmental substances, the average concentration of mold was 57.0 CFU/m3 for non-asthmatics and 14.5 CFU/m3 for asthmatics, showing a statistically significant difference. The average concentration of house dust mites was 338.9 ng/g in non-asthmatics and 79.5 ng/g in asthmatics, showing a statistically significant difference.

A study was conducted to evaluate the proper particle cleaned air changes per hour (PCH) in apartment buildings and school classrooms. The concept of PCH was newly introduced. The PCH can be expressed as the clean air delivery rate (CADR) per space volume. The PCH includes the filtering effect with air changes per hour (ACH). A method for calculating the proper PCH was theoretically proposed and experimentally verified. The proper PCH to effectively control ultrafine particles in apartments and school classrooms was found to be 4.0/h and 4.2/h, respectively. In general, air cleaners and mechanical ventilation devices are often used together in apartments and school classrooms. In such cases, it is important to consider the proper PCH of each device and control it for energy-efficient operation. In addition, in times of concern for infection such as COVID-19, it will be necessary to operate the PCH at 6.0/h or more to minimize the probability of infection.

This study aimed to evaluate the performance criteria of low-noise asphalt pavements under laboratory conditions. Laboratory tests were performed on eight porous and three non-porous asphalt mixtures. Draindown, Cantabro, tensile strength ratio (TSR), and dynamic stability tests were conducted to evaluate durability. The functionality was assessed using sound-absorption and indoorpermeability- coefficient tests. The laboratory results showed that all mixtures satisfied the quality standards for the draindown and TSR tests. In the dynamic stability test, all the mixtures demonstrated adequate rutting resistance. For porous mixtures, the Cantabro test results indicated sufficient shatter resistance and the indoor-permeability-coefficient test confirmed proper drainage performance. All mixtures exhibited satisfactory sound absorption, with the porous mixtures exhibiting slightly better sound absorption than the non-porous mixtures. Both porous and non-porous mixtures are durable and functional and are used in Korea. Future field tests are required to evaluate the noise reduction performance under different conditions and to compare the in-situ performance results with those from laboratory tests.

콘크리트 포장의 평탄성과 내구성은 환경 조건에 크게 영향을 받으며, 슬래브 상하부 간의 온습도 차이는 부등건조수축 및 와핑 (Warping) 현상을 유발하여 포장의 장기 성능 저하를 초래할 수 있다. 이는 주행성 저하, 균열 발생, 유지보수 비용 증가의 원인이 되 며, 특히 터널과 같은 특수 환경에서는 상하부 간의 습도 차이가 더욱 크게 나타나 부등건조수축이 심화될 가능성이 높다. 터널 내부 는 직사광선의 영향을 받지 않지만, 통풍이 잘 이루어져 건조한 환경이 조성되며, 이러한 조건에서는 슬래브 상부에서 수분 손실이 가 속화되고 하부는 습윤 상태를 유지하여 상하부 간의 큰 습도 차이를 발생시킨다. 이는 슬래브의 비균일한 수분 이동을 유발하여 부등 건조수축을 더욱 크게 발생하게 한다. 국내에서는 터널 길이가 500m 이상인 장대 터널에서 콘크리트 포장 적용이 증가하고 있으며, 아스팔트 포장 대비 화재 시 유독가스 발생 위험이 낮다는 이유로 국토교통부에서 콘크리트 포장을 권장하고 있다. 이로 인해 터널 내 콘크리트 포장의 사용이 증가하고 있 으나, 기상환경 변화 및 습도 관리 미흡으로 인해 콘크리트 포장 줄눈부에서의 평탄성 불량 문제가 빈번하게 발생하고 있다. 이러한 문제는 주행성 저하, 도로 이용자의 민원 증가 및 유지보수 비용 상승을 초래하고 있어, 구체적인 원인 분석과 대책 마련이 필요한 실 정이다. 따라서 본 연구는 터널과 같은 특수 환경에서 습도 조건이 콘크리트 슬래브의 부등건조수축에 미치는 영향을 실험적으로 분석하고, 슬래브의 수평 변형률 및 수직 변위를 측정하여 건조 수축에 따른 변형 거동을 정량적으로 평가하고자 하였다. 다양한 습도 조건에서 슬래브의 변형 양상을 비교 분석함으로써, 터널 환경에 적합한 콘크리트 포장 설계 및 유지관리 기준을 제시하고, 콘크리트 포장의 장 기 성능을 개선하기 위한 대책을 마련하고자 한다.

작은뿌리파리는 시설하우스에 발생하여 심각한 경제적 피해를 주고 있는 중요한 해충이다. 때문에 이를 방제하기 위한 다양한 연구 진행을 위해서는 간단하고 효과적인 대량 사육 방법이 요구된다. 본 연구는 시중에서 저렴하게 구입 가능한 기주인 강낭콩을 이용하여 작은뿌리파리의 대 량 사육 방법을 개발하고자 수행하였다. 시험은 강낭콩의 불린 기간 및 개수에 대한 작은뿌리파리의 산란수를 조사하였으며, 그 결과 3일 불린 강낭 콩에서 산란수가 108.2개로 가장 많았고, 강낭콩의 개수가 많을수록 산란수가 증가하였다. 또한 작은뿌리파리의 산란수가 가장 높게 나타난 3일 불 린 강낭콩배지와 기존에 사육배지로 보고된 감자디스크배지에서 산란수, 부화율, 용화율, 우화율, 생존수 및 알에서 성충까지 발육 기간을 비교하였 으며, 강낭콩배지에서 감자디스크배지보다 산란수가 8.5배 이상 높았고 용화율, 우화율, 생존수도 높게 나타났다. 알에서 성충까지 발육 기간은 강 낭콩배지에서 11.7일로 감자디스크배지보다 7일정도 빨리 우화하였다.

In this study, the operating performance of the heat pump dryer using the PF heat exchanger was experimentally studied. The capacity, COP, drain, SMER and operating status of the cooling cycle of the heat pump dryer were investigated according to the temperature, relative humidity and flow rate of the indoor air. Heat pump dryers are refrigerant-air system. For the dryer performance experiment, an air enthalpy calorimeter was used. From the experimental results, as the temperature, relative humidity, and flow rate of the inlet air increased, the capacity, COP, drain, SMER of the dryer increased. The change in the performance of the dryer was most affected by temperature. The P-h diagram of the cooling system showed that the operation status of the dryer was greatly affected by the indoor temperature. In addition, the SMER of the dryer showed a drying performance of about 3.38 kg/kWh or more within all experimental ranges.

PURPOSES : This study aimed to evaluate the performance of carbon-reduced asphalt mixtures based on asphalt binder and asphalt mixture tests. METHODS : A carbon-reducing asphalt additive was developed, and samples were prepared by mixing the additive(0.85%, 1.35%, and 1.85%) with virgin asphalt binder to measure changes in the asphalt’s physical properties based on the content of the developed additive. The basic physical properties the penetration, softening point, ductility, and rotational viscosity and performance grade of the samples were measured, and the optimal content of the additive was determined to be 1.35%. An asphalt mixture was produced using the optimal additive content of 1.35%, and stability, indirect tensile strength, tensile strength ratio(TSR), and dynamic stability tests were conducted to compare its performance with that of hot mixed asphalt(HMA). Additionally, a dynamic modulus test that could simulate various loading conditions was conducted. Fuel consumption and CO2 emission were measured at the plant. RESULTS : The developed additive had the effect of reducing the viscosity of the binder while maintaining properties similar to those of the base binder when used at the selected content. The mixture test confirmed that the physical properties related to strength tended to decrease slightly when the additive were applied; however, all specifications were satisfied. In the dynamic modulus test, the results were confirmed to be similar to those of HMA. The fuel consumption and CO2 emission were reduced by 25-30%. CONCLUSIONS : Evidently, asphalt mixtures with carbon-reducing additives can perform at a level equivalent to that of HMA. To bolster this conclusion, it is necessary to track the long-term performance of low-carbon asphalt mixtures on pilot roads.

Wall-embedded ventilators, which are commonly used for ventilation of buildings, greatly damage the aesthetics of the building due to pollutants such as dust and grease sticking to the fan and gaps of the ventilator as the period of use increases. For this aesthetic reason, it is often installed in a place that is not easily visible to people, and if the ventilation fan is not properly arranged and installed, it is difficult to maintain indoor air in an optimal state. In this study, the effect of the arrangement of ventilators on indoor ventilation performance was investigated. Comparisons were made between the case where three ventilators were concentrated and the case where they were spaced apart at regular intervals. It was found that the ventilation performance was different depending on the location where the ventilators were installed.

The objective of this study is to analyze the indoor air quality of multi-use facilities using an IoT-based monitoring and control system. Thise study aims to identify effective management strategies and propose policy improvements. This research focused on 50 multi-use facilities, including daycare centers, medical centers, and libraries. Data on PM10, PM2.5, CO2, temperature, and humidity were collected 24 hours a day from June 2019 to April 2020. The analysis included variations in indoor air quality by season, hour, and day of the week (including both weekdays and weekends). Additionally, ways to utilize IoT monitoring systems using big data were propsed. The reliability analysis of the IoT monitoring network showed an accuracy of 81.0% for PM10 and 76.1% for PM2.5. Indoor air quality varied significantly by season, with higher particulate matter levels in winter and spring, and slightly higher levels on weekends compared to weekdays. There was a positive correlation found between outdoor and indoor pollutant levels. Indoor air quality management in multi-use facilities requires season-specific strategies, particularly during the winter and spring. Furhtermore, enhanced management is necessary during weekends due to higher pollutant levels.

목적 : 본 연구는 국민건강영양조사 제8기(2019-2021) 원시자료를 이용하여, 생체지표를 통한 휘발성 실내환 경요인(휘발성 유기 화합물, VOCs)과 백내장의 연관성을 파악하고자 하였다. 방법 : 백내장 의사진단 여부 및 가정 실내공기질 측정에 참여한 만 40세 이상의 성인 총 1,150명을 대상으로 하였다. 일반적 특성에 따른 휘발성 실내환경요인의 농도와 백내장의 유 ‧무에 따른 휘발성 실내환경요인의 농도를 비교하기 위해 복합표본 기술통계 분석과 로지스틱회귀분석을 하였다. p<0.050인 경우 유의한 것으로 판단하였다. 결과 : 대부분의 실내 휘발성 환경오염물질의 생체지표는 백내장을 진단받은 대상자에서 높게 나타났다. 특히 Benzene, Xylene, Acrolein, 1-Bromopropane, 1,3-Butadiene의 생체지표 평균농도(GM)가 백내장 진단받은 대상자들이 유의하게 높게 나타났다. 연령, 성별, 결혼, 알콜, 흡연, 소득을 보정한 복합표본 로지스틱회귀분석에 서, 1,3-Butadiene의 생체지표는 약 2배(OR 1.905(95% CI: 1.001, 3.625))의 위험도로 백내장에 영향을 미칠 수 있는 것으로 나타났다. 결론 : 본 연구는 기존에 밝혀지지 않은 휘발성 실내환경요인과 백내장의 연관성을 파악함으로써, 일부 휘발성 실내환경물질은 백내장의 원인물질로 작용할 수 있는 가능성을 보여주었다.