Vehicle indoor air quality is determined by the complex interaction between interior material emissions (such as VOCs and aldehydes) and road-sourced pollutants. Despite growing public concern, existing frameworks often focus on single pollutants and lack a comprehensive health-impact-based evaluation. This study proposes the Vehicle Indoor Air Quality Index (VIAQI), which integrates acute, chronic, and odor-related exposures from internal sources with the infiltration of ambient air pollutants. The VIAQI adopts a safety-oriented priority (HQacute → SF → OA → HQchronic), reflecting the driver’s cognitive safety. It consists of 10 levels, ranging from Grade 1 (Excellent) to Grade 10 (Hazardous). Under three operating modes (AM, PM-6 hr, and DM), the analysis includes 21 chemical substances, as well as PM2.5 and NO2. Acute risks are assessed using OEHHA’s RELs, chronic risks via US EPA’s RfC, odor effects are quantified using a smell sensitivity index (SF), and outdoor air infiltration is evaluated through a weighted hazard index (OA). After evaluating actual new vehicles, Vehicles A, C, and D are categorized as Grade 3 (Good), while Vehicle B is categorized as Grade 9 (Very Unhealthy) and Vehicle E is categorized as Grade 10 (Hazardous). Notably, Vehicle B is rated Grade 9 due to acute toxicity risks identified through RELs-based assessment, even though it meets all current national regulatory standards. This highlights the existence of health hazards that conventional concentration-based regulations may overlook. As Korea’s first multi-dimensional evaluation system for vehicle air quality, the VIAQI offers a practical tool for manufacturers to implement quality control, set policy, and communicate consumer information, providing a proactive assessment based on real-world driving environments.
This study investigated indoor air quality (IAQ) in 302 facilities (consisting of 638 monitoring points) across five types of multi-use facilities for the health of vulnerable populations in Seoul. The facility types consisted of the following: ICPs (indoor children’s playgrounds), PCCs (postnatal care centers), ECFs (elderly care facilities), HCFs (health care facilities), and CCCs (child care centers). The investigation was carried out over a 1-year period, from January to December 2024. The objective of this research was to provide a scientific basis for IAQ management by identifying characteristics specific to facility types and potential risk levels for vulnerable populations in Seoul. Five indoor air pollutants (PM10, PM2.5, CO2, HCHO, and TAB) were continuously measured, and their concentration distributions, temporal variability, and multi-pollutant patterns were analyzed using data visualization and statistical methods. Boxplots and ridgeline plots characterized distributions and seasonality by facility type, while star plots and K-means clustering were used to examine multi-pollutant combinations and inter-facility pattern differences. Most measurements were within national IAQ standards. However, HCFs and PCCs exhibited relatively higher mean levels and variability of HCHO and TAB, indicating a greater need to control chemical and microbiological sources. CO2 concentrations approached or temporarily exceeded the national standard, particularly in HCFs, reflecting differences in occupant density, occupancy time, and ventilation management. Kruskal-Wallis and pairwise Wilcoxon rank-sum tests revealed statistically significant differences among facility types, particularly for CO2 and HCHO, consistent with the visualized multi-pollutant profiles. K-means clustering identified three IAQ patterns-multi-pollutant-elevated, activity/ventilation-influenced, and low-pollutionindicating that management needs may vary across facilities despite uniform national standards. These findings provide a methodological basis for IAQ big data analysis, policy making, and supporting future research integrating multi-year, outdoor, building, activity, and health data.
This study quantitatively evaluated the real-world performance of an IoTbased, context-aware mobile air purification system. Additionally, this system is proposed as a practical alternative to conventional stationary purifiers, overcoming their spatial limitations. To analyze concentration variations, removal efficiency, and air cleaning ratio (ACR) for PM2.5, PM10, and HCHO, three scenarios were tested: S1 (natural ventilation), S2 (stationary purifier), and S3 (IoT-based mobile air purification system). The mobile system (S3) achieved a 1.6-fold higher removal efficiency for PM2.5 compared with the stationary purifier (S2) and reduced the ACR to below 0.4 within 30 minutes after high-concentration events. In contrast, stationary purifiers required approximately 333 minutes to reach background levels (17.11 μg/m3), revealing about a 10-fold difference in cleaning speed. Monte Carlo simulations confirmed the consistent superiority of S3 for both particulate and gaseous pollutants, with HCHO concentrations 36.7% lower (90th percentile) than under S2. According to the health risk assessment, the asthma hospitalization rate decreased by over 40%, the HQ for PM2.5 decreased from 1.1 (S1) to 0.64 (S3), and the ECR for HCHO was 0.62 times that of S2. These findings highlight that spatial responsiveness and mobility, along with filter capacity, are key determinants of air purification performance. In conclusion, the mobile air purifier effectively overcomes the structural constraints of stationary devices and establishes a new paradigm for realtime, adaptive indoor air quality management that helps safeguard occupant health.
Over the past decade, the number of car owners has been steadily rising, leading to a significant increase in the amount of time spent inside cars. As a result, there has been a greater focus placed on the impact of indoor air quality of new cars on drivers and passengers. There has also been a growing awareness among consumers of environmental and health issues such as the odor and indoor air quality of new cars. However, Korea currently only regulates eight compounds according to the indoor air quality management standards for new cars, and there is no test method that reflects the Korean climate. Two domestic gas-powered cars, one imported gas-powered car, and two domestic electric cars were tested under the following conditions: 1) 25oC, 50% RH; 2) 25oC, 50% R.H, solar load (400 ± 50 W/m2); and 3) 60oC, 10% R.H. The results of the 25oC condition met the indoor air quality management standards for new cars by the Ministry of Land, Infrastructure and Transport. Additionally, it was confirmed that the higher the test temperature, the higher the emission of VOCs from the car interior. VOC emissions reached 761.1 μg/m3, and the TVOC concentration was 308,241.4 μg/m3. The odor of new cars increased from a dilution factor of 10 to 208. Two out of five cars exceeded the emission standards of the Ministry of Environment’s Malodor Prevention Act. An odor activity value (OAV) analysis confirmed that acetaldehyde was the highest contributor to odors. The TVOC concentration exceeded the domestic indoor air quality standards for multi-use facilities (1,000 μg/m3). The eight pollutants covered under TVOC management accounted for about 1~6%, while other pollutants were found to account for over 90%. Further studies should expand and review objective indicators that can best represent the indoor air quality of new cars.
This study analyzed policy measures to comprehensively achieve two goals: carbon neutrality in buildings and optimization of indoor air quality. While buildings account for approximately 40% of total energy consumption and greenhouse gas emissions, and present-day individuals spend 90% of their daily lives indoors, both goals are critically important. However, these objectives often conflict with each other, and current policies have limitations in effectively addressing this complex relationship. Analysis of related policies, including the Green Building Creation Support Act and the Indoor Air Quality Management Act, revealed significant drawbacks such as the lack of an integrated approach due to policy fragmentation, insufficient consideration of lifecycle carbon emissions, imbalance in economic incentive structures, and rigidity in technical standards. To overcome these challenges, this study proposes innovative improvement measures, including the following: establishing an integrated policy framework, introducing a multi-layered air quality management system, expanding performance-based design that simultaneously considers energy efficiency and indoor air quality, developing region-specific policies, implementing AI-based self-assessment systems, mandating green space ratios, controlling high-radon concentration areas, and expanding government incentives.
This study examined the influence of multiple factors—particularly occupant presence and air purifier operation—on indoor PM2.5 concentrations across 104 households in the Seoul metropolitan area. Both indoor and outdoor PM2.5 concentrations were continuously monitored and integrated with time-specific survey data to analyze spatial and temporal patterns of indoor exposure. Results showed that occupant presence significantly elevated indoor PM2.5 concentrations, especially during periods of high activity (08:00~15:00 and 18:00~20:00). The indoor/outdoor (I/ O) concentration ratio was also significantly higher during these periods, indicating that occupant activities were a major contributor to indoor PM2.5 concentrations. Air purifier use was found to be associated with a consistent reduction in indoor PM2.5 concentrations, regardless of occupancy status. Notably, the I/O ratio also decreased when air purifiers were in operation, demonstrating their effectiveness in controlling both indoor emissions and the infiltration of outdoor pollutants. These findings provide empirical evidence of the multifactorial dynamics governing indoor PM2.5 exposure and highlight the importance of occupant-centered and time-specific strategies for effective residential air quality management.
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.
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.
Objectives: The main purpose of this study was to identify problems such as cooking fumes and lack of ventilation in school cafeterias and evaluate the improvement in the reduction of indoor pollutants in the cooking rooms through renovation. Methods: Three schools were selected for renovation and the spatial structures and air conditioning system of the cafeterias and cooking rooms wre investigated after renovation. The air conditioning systems were improved by the renovation work according to the characteristics of each school, and the concentration of indoor pollutants was measured and evaluated through CFD analysis. Results: The concentration of indoor pollutants in the cafeterias and cafe rooms was decreased after renovation. Conclusion: Air conditioning systems in the schools cafeterias and cooking rooms were improved in order to solve the problems of ventilation, and the indoor air quality improvement rate ranged from a minimum of 11% to a maximum of 40%. The renovation of cafeterias and cooking rooms was conducted to optimize the ventilation systems and this contributed to indoor air quality improvement by preventing the inflow of pollutants.
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.
Passengers on public buses operating in the metropolitan area are exposed to the closed indoor air for minutes to hours. The indoor air quality of buses is mostly controlled through ceiling-mounted ventilation and filtration devices. A simulation study using a commercial code was conducted for fluid flow analysis to evaluate the potential effectiveness of an air purifier that can be inserted into bus windows to supply clean air from the outside to the inside. As a result of field measurements, the average CO2 concentration inside the bus during morning and evening rush hours ranged from 2,106±309 ppm to 3,308 ± 255 ppm depending on the number of passengers on board. This exceeded the Guideline for Public Transportation. The optimal installation position of an air purifier appeared to be the front side of the bus. In fact, even a low diffusing flow velocity of 0.5m/s was effective enough to maintain a low concentration of CO2 throughout the indoor space. Based on numerical analysis predictions with 45 passengers on board, the maximum CO2 concentration in the breathing zone was 2,203 ppm with the operation of an air purifier.
Vulnerable populations in healthcare facilities are more sensitive to exposure to indoor air pollutants, and therefore are more affected by such pollutants than the general population. This was the underlying reason why studies of indoor air pollutant concentration distribution and health risk assessment have been conducted targeting facilities, such as daycare centers, medical facilities, elderly care facilities, and postnatal care centers. However, previous studies have mainly focused on daycare and medical facilities for their research, and relatively speaking, studies conducted on the other venues are lacking. Therefore, this study aims to present the current status of indoor air quality and perform a health risk assessment in regard to Formaldehyde exposure at postnatal care centers and elderly care facilities. Here, the study focused on facilities that had undergone pollution level inspections from January 2017 to December 2021. A total of 81 postnatal care centers and 48 elderly care facilities were selected as the subject of the study. Then, the study utilized concentrations of five elements (CO2, HCHO, PM10, PM2.5, TBC) to determine the status of indoor air quality of both postnatal care centers and elderly care facilities. For health risk assessment, HCHO concentration was used. The investigation demonstrated that the yearly average concentration of the five elements stood within the indoor air quality maintenance standards, and the ratio of PM2.5 to PM10 in the two types of facilities was distributed as high as about 70%. In addition, the study showed that HCHO and TBC demonstrated a positive correlation when the relationship between indoor temperature and humidity with the five elements was examined. The health risk assessment showed that the cancer risk level of postnatal care center users stood below 10-6, below the level that is perceived as an acceptable risk. The cancer risk of workers from both postnatal care centers and elderly care facilities and elderly care facility users exceeded the acceptable risk level of 10-6, but was shown to be below 10-4, the maximum acceptable risk.
Fungi are organisms that must be monitored and controlled in order to preserve valuable paper records. They reduce the quality of paper records by degradation and/or discoloration. As an effort to understand fungal contamination in the National Archives of Korea, the concentration of fungi in the indoor air of the unsterilized record rooms has been reported. However, what species are present in the facilities is not much known. In the present study, we examined the fungi isolated from the National Archives of Korea and found among them that there are fungal species which are newly documented in Korea. They were identified based on morphological properties and nucleotide sequences analysis of the polymerase chain reaction-amplified the internal transcribed spacer region of rDNA, calmodulin gene, and beta-tubulin gene. We report Cladosporium parahalotolerans, Cladosporium subuliforme, Ochroconis mirabilis, Penicillium angulare, and Penicillium fundyense as new instances of fungal species in Korea. Among these five species, P. angulare is known to able to produce cellulase and O. mirabilis as an opportunistic pathogen of human and animals.
This study measured the suspended fungal concentration in indoor multiple facilities nationwide. The regions were selected as representative cities by region: Seoul, Gyeonggi (Incheon), Gangwon, Gwangju, Daejeon, and Busan. A total of 2028 regional comparisons, including department stores, schools, public toilets, libraries, and banks, subway, sports facilities and comparative analysis were conducted for each multi-use facility industry. Among the nationwide, Among the regions, the average concentration of floating mold in indoor multi-use facilities was the lowest in Busan at 394.67 CFU/m3, followed by Gyeonggi and Incheon 487.90 CFU/m3, Seoul 542.84 CFU/m3, Daejeon 809.30 CFU/m3, Gangwon 1,145.22 CFU/m3, Gwangju was 1,371.10 CFU/m3 in the order. Busan was the lowest, and Gangwon was the highest. The reason that Busan, which has a high average temperature and population density, shows a lower mold concentration than Gangwon, is that floating mold in the indoor air is not affected by the external atmospheric environment, population density, and number of facility users. Although it cannot be said that there is no influence of the atmospheric environment, it was found that the indoor environment has different characteristics from the outdoor environment. The importance of air quality management has been confirmed, and further, it is necessary to subdivide the management standards by region and multi-use facilities, and the management standards need to be converted to maintenance rather than recommendations.