Jung-Hwan Kwon, Yeonjeong Ha, Ji-Hoon Seo, Pil-Gon Kim
Increased use of diverse consumer products generates many chemicals of potential health concerns. For monitoring personal exposure to those chemicals, passive samplers are inexpensive methods for assessing time-weighted average exposure. This review summarizes the application of passive sampling methods for assessing exposure to hazardous chemicals released from consumer products in indoor environments, discussing the principles of passive sampling, various sampler types, and their effectiveness in monitoring different classes of pollutants, including volatile organic compounds (VOCs), semi–volatile organic compounds (SVOCs), and reactive substances. Challenges associated with calibration and validation for specific chemicals are addressed. The review highlights the potential of passive sampling as a cost-effective tool for large-scale monitoring and emphasizes the need for future research to develop advanced techniques, such as miniaturized multianalyte and time-resolved samplers, to achieve comprehensive exposure assessments including transformation products and capture complex indoor air pollution dynamics.
{"title":"Use of Passive Samplers for Estimating the Exposure to Household Chemicals: A Critical Review","authors":"Jung-Hwan Kwon, Yeonjeong Ha, Ji-Hoon Seo, Pil-Gon Kim","doi":"10.1155/ina/9930242","DOIUrl":"https://doi.org/10.1155/ina/9930242","url":null,"abstract":"<p>Increased use of diverse consumer products generates many chemicals of potential health concerns. For monitoring personal exposure to those chemicals, passive samplers are inexpensive methods for assessing time-weighted average exposure. This review summarizes the application of passive sampling methods for assessing exposure to hazardous chemicals released from consumer products in indoor environments, discussing the principles of passive sampling, various sampler types, and their effectiveness in monitoring different classes of pollutants, including volatile organic compounds (VOCs), semi–volatile organic compounds (SVOCs), and reactive substances. Challenges associated with calibration and validation for specific chemicals are addressed. The review highlights the potential of passive sampling as a cost-effective tool for large-scale monitoring and emphasizes the need for future research to develop advanced techniques, such as miniaturized multianalyte and time-resolved samplers, to achieve comprehensive exposure assessments including transformation products and capture complex indoor air pollution dynamics.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/9930242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145750790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anurag Barthwal, Nikhil Kumar, Shwetank Avikal, Nelson Decontee Wroye
Maintaining a healthy indoor environment is crucial for a productive and well-balanced life. This study proposes a comprehensive indoor environment index (IEI) that integrates air quality, thermal, visual, and acoustical comfort indicators using sensor data. Major indoor pollutants (CO, PM2.5, and PM10), temperature, relative humidity, noise levels, and illuminance are combined through an analytic hierarchy process to formulate the IEI. A hybrid deep learning model based on a CNN-GRU architecture is then used to forecast indoor environmental states across four categories (severe, very poor, poor, and satisfactory). ANOVA and Tukey′s HSD analysis confirmed significant differences among these categories. The model was trained on 80% of the dataset and tested on the remaining 20%, with performance evaluated using precision, recall, F1-score, and AUC-ROC. The proposed approach achieved a mean F1-score of 0.96, demonstrating high predictive accuracy and reliability. These results confirm the robustness and reliability of the proposed model. The study demonstrates its potential for supporting accurate indoor environmental quality prediction and providing a foundation for informed building management decisions.
{"title":"Indoor Environmental Quality Prediction Using Hybrid Deep Learning and a Comprehensive Environment Index","authors":"Anurag Barthwal, Nikhil Kumar, Shwetank Avikal, Nelson Decontee Wroye","doi":"10.1155/ina/9243817","DOIUrl":"https://doi.org/10.1155/ina/9243817","url":null,"abstract":"<p>Maintaining a healthy indoor environment is crucial for a productive and well-balanced life. This study proposes a comprehensive indoor environment index (IEI) that integrates air quality, thermal, visual, and acoustical comfort indicators using sensor data. Major indoor pollutants (CO, PM<sub>2.5</sub>, and PM<sub>10</sub>), temperature, relative humidity, noise levels, and illuminance are combined through an analytic hierarchy process to formulate the IEI. A hybrid deep learning model based on a CNN-GRU architecture is then used to forecast indoor environmental states across four categories (severe, very poor, poor, and satisfactory). ANOVA and Tukey′s HSD analysis confirmed significant differences among these categories. The model was trained on 80% of the dataset and tested on the remaining 20%, with performance evaluated using precision, recall, <i>F</i>1-score, and AUC-ROC. The proposed approach achieved a mean <i>F</i>1-score of 0.96, demonstrating high predictive accuracy and reliability. These results confirm the robustness and reliability of the proposed model. The study demonstrates its potential for supporting accurate indoor environmental quality prediction and providing a foundation for informed building management decisions.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/9243817","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145750787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alexandru Cernei, Frédéric Thevenet, Florin Bode, Marie Verriele, Ilinca Nastase
Computational fluid dynamics (CFD) is a powerful method for predicting and optimising indoor environmental conditions due to its ability to simulate complex airflow patterns, temperature distributions and contaminant dispersion with high spatial resolution. However, the accuracy and reliability of CFD simulations depend strongly on robust verification and validation methodologies. This review critically examines how numerical models are experimentally validated in the context of indoor environmental quality (IEQ) studies, with a focus on the parameters used and methods adopted by researchers. The central objective is to understand if and how validation is performed and which variables are typically considered. The findings reveal major inconsistencies in the current literature regarding the choice of validation parameters, sensor deployment strategies and the reporting of calibration procedures, which limit reproducibility and cross-study comparability. To address these gaps, the review proposes a novel validation framework that integrates both thermal comfort and indoor air quality (IAQ) metrics into a unified approach. The review also reflects upon the advantages of advanced thermal manikins as comprehensive validation instruments capable of capturing the dynamic interaction between the human body and indoor environments, thereby enhancing the realism and applicability of CFD simulations in IEQ research. This work is, to the authors′ knowledge, the first to systematically dissect existing validation methodologies for CFD simulations of pollutant transport in indoor environments while simultaneously proposing a structured pathway forward, paving the way for standardisation efforts and the integration of more accurate, cost-effective monitoring approaches in both research and practice.
{"title":"Critical Review of Current Validation Methodologies and Future Developments in CFD-Based Indoor Environmental Quality Analysis","authors":"Alexandru Cernei, Frédéric Thevenet, Florin Bode, Marie Verriele, Ilinca Nastase","doi":"10.1155/ina/6601284","DOIUrl":"https://doi.org/10.1155/ina/6601284","url":null,"abstract":"<p>Computational fluid dynamics (CFD) is a powerful method for predicting and optimising indoor environmental conditions due to its ability to simulate complex airflow patterns, temperature distributions and contaminant dispersion with high spatial resolution. However, the accuracy and reliability of CFD simulations depend strongly on robust verification and validation methodologies. This review critically examines how numerical models are experimentally validated in the context of indoor environmental quality (IEQ) studies, with a focus on the parameters used and methods adopted by researchers. The central objective is to understand if and how validation is performed and which variables are typically considered. The findings reveal major inconsistencies in the current literature regarding the choice of validation parameters, sensor deployment strategies and the reporting of calibration procedures, which limit reproducibility and cross-study comparability. To address these gaps, the review proposes a novel validation framework that integrates both thermal comfort and indoor air quality (IAQ) metrics into a unified approach. The review also reflects upon the advantages of advanced thermal manikins as comprehensive validation instruments capable of capturing the dynamic interaction between the human body and indoor environments, thereby enhancing the realism and applicability of CFD simulations in IEQ research. This work is, to the authors′ knowledge, the first to systematically dissect existing validation methodologies for CFD simulations of pollutant transport in indoor environments while simultaneously proposing a structured pathway forward, paving the way for standardisation efforts and the integration of more accurate, cost-effective monitoring approaches in both research and practice.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/6601284","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145750662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Seyed Hamidreza Nabaei, Ryan Lenfant, Viswajith Govinda Rajan, Dong Chen, Michael P. Timko, Bradford Campbell, Arsalan Heydarian
Buildings need practical ways to monitor indoor air quality (IAQ) beyond aggregate TVOC readings. We show that low-cost commercial VOC sensors, coupled with machine learning, can recover compound-specific information from plant-emitted terpenes, enabling practical, real-time bioindication in buildings. In an office testbed, we exposed sensors to 16 terpenes and trained random forest, support vector machine, and XGBoost models on time series features. The models detected “any terpene versus background” at 97%–100% accuracy, identified “plants versus background” at ~100%, and discriminated among individual compounds with accuracies up to 96%. Feature importance emphasized temporal dynamics (e.g., autocorrelation lags and entropy measures) rather than static peaks, highlighting the value of sequence information for commodity hardware. Complementary experiments with living basil plants showed reproducible VOC profiles and stress-induced bursts of ~70–100 ppb, confirming in situ feasibility. A placement analysis across 13 locations indicated that the HVAC return-air duct provides the most actionable, room-integrated signal for deployment, balancing accuracy and coverage. Together, these results establish a pathway from TVOC to compound-aware IAQ using sensors already common in smart buildings, with immediate applications to exposure triage and demand-controlled ventilation, and a foundation for plant-integrated environmental monitoring.
{"title":"Detecting Plant VOCs With Indoor Air Quality Sensors","authors":"Seyed Hamidreza Nabaei, Ryan Lenfant, Viswajith Govinda Rajan, Dong Chen, Michael P. Timko, Bradford Campbell, Arsalan Heydarian","doi":"10.1155/ina/7134467","DOIUrl":"https://doi.org/10.1155/ina/7134467","url":null,"abstract":"<p>Buildings need practical ways to monitor indoor air quality (IAQ) beyond aggregate TVOC readings. We show that low-cost commercial VOC sensors, coupled with machine learning, can recover compound-specific information from plant-emitted terpenes, enabling practical, real-time bioindication in buildings. In an office testbed, we exposed sensors to 16 terpenes and trained random forest, support vector machine, and XGBoost models on time series features. The models detected “any terpene versus background” at 97%–100% accuracy, identified “plants versus background” at ~100%, and discriminated among individual compounds with accuracies up to 96%. Feature importance emphasized temporal dynamics (e.g., autocorrelation lags and entropy measures) rather than static peaks, highlighting the value of sequence information for commodity hardware. Complementary experiments with living basil plants showed reproducible VOC profiles and stress-induced bursts of ~70–100 ppb, confirming in situ feasibility. A placement analysis across 13 locations indicated that the HVAC return-air duct provides the most actionable, room-integrated signal for deployment, balancing accuracy and coverage. Together, these results establish a pathway from TVOC to compound-aware IAQ using sensors already common in smart buildings, with immediate applications to exposure triage and demand-controlled ventilation, and a foundation for plant-integrated environmental monitoring.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/7134467","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145750528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emad Noaime, Mohmmed Mashary Alnaim, Mohamed Bechir Ben Hamida
This study investigates windcatchers as sustainable ventilation solutions in architecture, addressing energy efficiency and reduced fossil fuel dependence. Traditional windcatchers, passive cooling devices, have been enhanced with sealed doors and windows to overcome earlier limitations. Focusing on dry climates, this research evaluates the performance of windcatchers in maintaining indoor comfort. Using computational fluid dynamics (CFD) through Comsol Multiphysics, factors like output velocity, pressure differential, and mass flow rate are assessed, with Hail City selected for testing. The study also examines the impact of inlet orientation on airflow dynamics, temperature, and humidity distribution within a building, comparing two cases: lateral inlet (Case 1) and top-side inlet (Case 2). Results show that Case 2 achieves higher velocities, particularly at the exit, where speeds are 3.5 times greater than in Case 1. Temperature distributions vary, with Case 1 demonstrating lower exit temperatures and Case 2 exhibiting reduced inlet temperatures. Humidity rises with inlet speed in both cases, more notably in Case 1. These findings highlight the importance of inlet orientation in enhancing airflow efficiency and optimizing environmental conditions, offering valuable insights for architects and engineers aiming to integrate sustainable design elements for improved indoor comfort and energy savings.
{"title":"Reinventing the Windcatcher for Sustainable Saudi Homes: Transforming Urban Setbacks Into Passive Cooling Spaces","authors":"Emad Noaime, Mohmmed Mashary Alnaim, Mohamed Bechir Ben Hamida","doi":"10.1155/ina/9094416","DOIUrl":"https://doi.org/10.1155/ina/9094416","url":null,"abstract":"<p>This study investigates windcatchers as sustainable ventilation solutions in architecture, addressing energy efficiency and reduced fossil fuel dependence. Traditional windcatchers, passive cooling devices, have been enhanced with sealed doors and windows to overcome earlier limitations. Focusing on dry climates, this research evaluates the performance of windcatchers in maintaining indoor comfort. Using computational fluid dynamics (CFD) through Comsol Multiphysics, factors like output velocity, pressure differential, and mass flow rate are assessed, with Hail City selected for testing. The study also examines the impact of inlet orientation on airflow dynamics, temperature, and humidity distribution within a building, comparing two cases: lateral inlet (Case 1) and top-side inlet (Case 2). Results show that Case 2 achieves higher velocities, particularly at the exit, where speeds are 3.5 times greater than in Case 1. Temperature distributions vary, with Case 1 demonstrating lower exit temperatures and Case 2 exhibiting reduced inlet temperatures. Humidity rises with inlet speed in both cases, more notably in Case 1. These findings highlight the importance of inlet orientation in enhancing airflow efficiency and optimizing environmental conditions, offering valuable insights for architects and engineers aiming to integrate sustainable design elements for improved indoor comfort and energy savings.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/9094416","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145686455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}