4.7 Review

Ventilation strategies to reduce airborne transmission of viruses in classrooms: A systematic review of scientific literature

Related references

Note: Only part of the references are listed.
Article Engineering, Chemical

Simultaneous temporal, spatial and size-resolved measurements of aerosol particles in closed indoor environments applying mobile filters in various use-cases

Julia Szabadi et al.

Summary: This paper focuses on the simultaneous, time- and space-resolved measurements of particle size distributions in different closed indoor environments using mobile air filters. The experiments show that these air filters, equipped with high-performance filter media, efficiently remove submicron particles over time. However, the real-room scenarios reveal slower particle decay than predicted, and the filters cannot prevent close distance transmission of submicron aerosol particles.

JOURNAL OF AEROSOL SCIENCE (2022)

Article Construction & Building Technology

Airflow deflectors of external windowsto induce ventilation: Towards COVID-19 prevention and control

Wanqiao Che et al.

Summary: This study investigates the effectiveness of airflow deflectors in improving the airflow diffusion performance and preventing disease transmission in naturally ventilated classrooms. The results show that using airflow deflectors can reduce the infection risk and provide guidance for the design of classrooms for epidemic prevention and control.

SUSTAINABLE CITIES AND SOCIETY (2022)

Article Construction & Building Technology

Measured influence of overhead HVAC on exposure to airborne contaminants from simulated speaking in a meeting and a classroom

Brett C. Singer et al.

Summary: Tracer gas experiments were conducted to study the dispersion of contaminants from simulated speaking in physically distanced meeting and classroom configurations. Results showed that chilled or neutral supply air provided good mixing, while thermal stratification during heating led to higher exposure variations. Operating two within-zone air cleaners together vertically in the room helped mitigate elevated exposure variations.

INDOOR AIR (2022)

Article Construction & Building Technology

Airborne and aerosol pathogen transmission modeling of respiratory events in buildings: An overview of computational fluid dynamics

Yahya Sheikhnejad et al.

Summary: This study reviews the capabilities and limitations of computational fluid dynamics (CFD) modeling, experimental techniques for measuring characteristics of airborne pathogen droplet transmissions, and relevant clinical data. The study identifies uncertainties and inconsistencies in clinical data and highlights the gaps and limitations in CFD analysis.

SUSTAINABLE CITIES AND SOCIETY (2022)

Article Construction & Building Technology

The effect of a mobile HEPA filter system on 'infectious' aerosols, sound and air velocity in the SenseLab

Philomena M. Bluyssen et al.

Summary: Efficiency of a mobile HEPA filter system in reducing airborne transmission of infectious aerosols was tested, showing better performance than no ventilation and some mixing ventilation regimes. However, position, setting, and room size may affect the system's performance, noise levels, and draught effects.

BUILDING AND ENVIRONMENT (2021)

Review Construction & Building Technology

Review and comparison of HVAC operation guidelines in different countries during the COVID-19 pandemic

Mingyue Guo et al.

Summary: This paper reviews and compares heating, ventilating, and air-conditioning-related guidelines in several major countries and regions, finding that while most recommendations are consistent, there are still some conflicting details, reflecting the uncertainty surrounding the transmission mechanism and characteristics of COVID-19 in buildings.

BUILDING AND ENVIRONMENT (2021)

Article Construction & Building Technology

Patterns of SARS-CoV-2 aerosol spread in typical classrooms

Gerhard K. Rencken et al.

Summary: Recent studies have shown that long-range spread of aerosols, specifically bio-aerosols, is responsible for infections in public spaces. Through computational fluid dynamics and experimental results, the distribution of aerosol concentration in a classroom under different ventilation conditions was explored and compared with well-mixed assumptions. Ventilation systems such as ceiling diffusers and open windows can significantly impact aerosol concentration levels at breathing height in indoor spaces.

BUILDING AND ENVIRONMENT (2021)

Article Construction & Building Technology

Mitigating aerosol infection risk in school buildings: the role of natural ventilation, volume, occupancy and CO2 monitoring

Alessandro Zivelonghi et al.

Summary: Issues related to aerosol physics and infection risk in school buildings are not properly recognized in safety regulations. Precise investigation of ventilation factors and occupancy rates in each classroom is needed, but most schools lack necessary systems and sensors.

BUILDING AND ENVIRONMENT (2021)

Article Construction & Building Technology

The design of safe classrooms of educational buildings for facing contagions and transmission of diseases: A novel approach combining audits, calibrated energy models, building performance (BPS) and computational fluid dynamic (CFD) simulations

Fabrizio Ascione et al.

Summary: The proposed study aims to provide suggestions for renovating educational buildings to make University classrooms safe and sustainable indoor spaces in response to the 2020 SARS-CoV-2 pandemic. By conducting experimental and numerical investigations, the authors propose a comprehensive retrofit design approach to improve classroom quality and safety, highlighting the importance of HVAC systems and equipment in indoor air quality management.

ENERGY AND BUILDINGS (2021)

Article Engineering, Chemical

Risk assessment of airborne transmission of COVID-19 by asymptomatic individuals under different practical settings

Siyao Shao et al.

Summary: The lack of quantitative risk assessment of airborne transmission of COVID-19 under practical settings leads to uncertainties and inconsistencies in preventive measures. Ventilation design is critical for reducing the risk of particle encounters, inappropriate design can create hot spots with higher risks and enhance particle deposition causing surface contamination. Faceted particles from normal breathing are correlated with breathing depth.

JOURNAL OF AEROSOL SCIENCE (2021)

Review Immunology

Outdoor Transmission of SARS-CoV-2 and Other Respiratory Viruses: A Systematic Review

Tommaso Celeste Bulfone et al.

Summary: Studies have shown that only a small proportion of global SARS-CoV-2 infections have occurred outdoors, with indoor transmission being more likely compared to outdoor transmission. There is considerable heterogeneity in study quality and definitions of outdoor settings, which limits the ability to draw definitive conclusions about outdoor transmission risks.

JOURNAL OF INFECTIOUS DISEASES (2021)

Article Construction & Building Technology

Exploring the potentials of personalized ventilation in mitigating airborne infection risk for two closely ranged occupants with different risk assessment models

Wenbing Liu et al.

Summary: In the context of COVID-19, personalized ventilation (PV) is considered a promising solution to reduce airborne transmission risk. Experimental results showed that PV can effectively reduce infection risk, with different orientations and operation modes affecting its performance significantly. The optimal design of PV for closely ranged occupants was discussed, providing valuable insights for risk assessment and control.

ENERGY AND BUILDINGS (2021)

Article Environmental Sciences

CO2 concentration monitoring inside educational buildings as a strategic tool to reduce the risk of Sars-CoV-2 airborne transmission

Alessia Di Gilio et al.

Summary: The study aimed to assess the risk inside schools by monitoring CO2 levels, finding that implementing detailed ventilation protocols and real-time monitoring of CO2 concentrations can improve air quality in classrooms and reduce the risk of SARS-CoV-2 transmission.

ENVIRONMENTAL RESEARCH (2021)

Article Construction & Building Technology

High energy efficiency ventilation to limit COVID-19 contagion in school environments

Luigi Schibuola et al.

Summary: By increasing ventilation rates, particularly through strong mechanical ventilation, indoor viral concentration and infection risk can be significantly reduced, making masks effective even at 50% usage levels, and bringing the reproduction number down to below 1.

ENERGY AND BUILDINGS (2021)

Article Environmental Sciences

Experimental and simulated evaluations of airborne contaminant exposure in a room with a modified localized laminar airflow system

Zhu Cheng et al.

Summary: The study found that a localized laminar airflow ventilation system can efficiently provide fresh air to the breathing zone without sacrificing the thermal environment around human, making it suitable for areas like bedrooms and living rooms where maintaining good indoor air quality is desired.

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH (2021)

Article Mechanics

SARS-CoV-2 transmission in classroom settings: Effects of mitigation, age, and Delta variant

Aaron Foster et al.

Summary: Traditional classroom settings have been limited during the COVID-19 pandemic due to their potential to transmit the virus. Studies have shown that the most effective mitigation strategies involve using face coverings and ventilation systems combined with air purifiers, while desk shields have proven to be ineffective. Additionally, reduced pulmonary and viral emission rates in small children in elementary school settings drive lower transmission rates than those observed in classrooms with adults, even when considering the Delta variant.

PHYSICS OF FLUIDS (2021)

Article Mechanics

Estimating COVID-19 exposure in a classroom setting: A comparison between mathematical and numerical models

Aaron Foster et al.

Summary: The COVID-19 pandemic has prompted studies of airborne transmission risk using Wells-Riley and computational fluid dynamics (CFD) models. Ventilation with moderate filtration in a classroom setting can reduce infection transmission probability significantly. Individual transmission route infection probabilities vary significantly, with local air patterns being the main driving factor.

PHYSICS OF FLUIDS (2021)

Article Environmental Sciences

The Impact of Large Mobile Air Purifiers on Aerosol Concentration in Classrooms and the Reduction of Airborne Transmission of SARS-CoV-2

Finn F. Duill et al.

Summary: In a primary school in Germany, researchers tested the effectiveness of three large mobile air purifiers with HEPA filters and found that they can significantly reduce aerosol particle concentration. Additionally, differences were observed among the air purifiers in terms of particle decay rate, noise level, and flow velocity.

INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH (2021)

Article Construction & Building Technology

Airborne infection risks of SARS-CoV-2 in US schools and impacts of different intervention strategies

Yifang Xu et al.

Summary: The study estimated the airborne infection risk of SARS-CoV-2 in 111,485 U.S. public and private schools and found that implementing intervention strategies is crucial to reducing the risk. Air filtration was identified as the most effective strategy, and for most schools, it is necessary to adopt combined intervention strategies to ensure the infection risk is below 1%.

SUSTAINABLE CITIES AND SOCIETY (2021)

Review Construction & Building Technology

Recent research on expiratory particles in respiratory viral infection and control strategies: A review

Yunchen Bu et al.

Summary: This study reviews recent research on expiratory particles and flow characteristics, with a focus on different respiratory activities, to guide the reduction of viral infection risk in built environments. Airborne transmission is a significant route of viral transmission, impacted by relative humidity and temperature. Future research and control strategies are needed to better predict infection potential and enhance indoor viral infection control.

SUSTAINABLE CITIES AND SOCIETY (2021)

Article Thermodynamics

Effect of under-floor air distribution system to prevent the spread of airborne pathogens in classrooms

Chang Heon Cheong et al.

Summary: The study found that the UFAD system is more effective in preventing the spread of airborne pathogens compared to the conventional mixed-mode ventilation system, but there are still risks around the exhaust area. Recommendations include installing exhaust vents away from breathing areas and implementing novel methods to reduce infection risks from students to teachers in front of the classroom.

CASE STUDIES IN THERMAL ENGINEERING (2021)

Article Mechanics

Transmission and reduction of aerosols in classrooms using air purifier systems

Sebastian Burgmann et al.

Summary: The study analyzed the transmission of aerosols in a classroom with an air purifier system, showing a significant reduction of airborne particles. Experimental and numerical simulation results validated the importance of air purifier systems in reducing the risk of infection.

PHYSICS OF FLUIDS (2021)

Article Environmental Sciences

Natural ventilation strategy and related issues to prevent coronavirus disease 2019 (COVID-19) airborne transmission in a school building

Sowoo Park et al.

Summary: The World Health Organization warns of airborne transmission of SARS-CoV-2 in poorly ventilated indoor spaces. Ventilation plays a crucial role in reducing the risk of virus transmission. Studies show that opening windows can significantly increase ventilation rates, especially in public buildings and shared spaces.

SCIENCE OF THE TOTAL ENVIRONMENT (2021)

Article Construction & Building Technology

A systematic approach to estimating the effectiveness of multi-scale IAQ strategies for reducing the risk of airborne infection of SARS-CoV-2

Jialei Shen et al.

Summary: This paper presents a systematic approach for evaluating the effectiveness of multi-scale IAQ control strategies in mitigating the infection risk of COVID-19. Various IAQ control strategies are introduced and evaluated for specific indoor spaces to reduce the risk of COVID-19 infection. These strategies can be applied in different scenarios to better prepare for possible future pandemics.

BUILDING AND ENVIRONMENT (2021)

Article Construction & Building Technology

Ventilation procedures to minimize the airborne transmission of viruses in classrooms

L. Stabile et al.

Summary: The key challenge of the COVID-19 pandemic is reducing transmission of SARS-CoV-2 through indoor air. Improved ventilation in crowded indoor environments like schools can help minimize airborne transmission, but there is uncertainty around required ventilation rates and achieving targets efficiently. The study explores using mechanical ventilation and ad-hoc airing procedures to mitigate airborne transmission risk in classrooms, proposing a feedback control strategy for naturally-ventilated classrooms.

BUILDING AND ENVIRONMENT (2021)

Article Construction & Building Technology

Measurements of exhaled airflow velocity through human coughs using particle image velocimetry

Mengtao Han et al.

Summary: This study measured airflow velocity of human coughs using high-frequency PIV technology to provide a detailed validation database for further research on the impact of cough airflow on virus transmission. It found differences in cough characteristics between males and females, as well as variations in average velocity and cough spread angles.

BUILDING AND ENVIRONMENT (2021)

Article Construction & Building Technology

Investigation of potential aerosol transmission and infectivity of SARS-CoV-2 through central ventilation systems

Leonard F. Pease et al.

Summary: This study evaluates the concentrations and probabilities of infection for both building interior and exterior exposure sources using a well-mixed model in a multiroom building served by a central air handling system. It found that slower air change rates reduce infectivity in connected rooms, filtration lowers the concentration and probability of infection the most in connected rooms, and increasing the outdoor air to 33% or using MERV-13 filter can significantly decrease infectivity in connected rooms.

BUILDING AND ENVIRONMENT (2021)

Article Biology

Assessing school-based policy actions for COVID-19: An agent-based analysis of incremental infection risk

Reyhaneh Zafarnejad et al.

Summary: The study proposed a new approach to model the spread of SARS-CoV-2 quanta in a closed classroom environment, taking into account student behavior regarding guideline compliance. The findings showed that traditional transmission models underestimated infection rates compared to the new approach; ventilation changes were effective in reducing transmission risk, but distancing practices had a greater impact; and the duration of the class was a significant factor in determining transmission risk.

COMPUTERS IN BIOLOGY AND MEDICINE (2021)

Review Engineering, Environmental

A critical review of heating, ventilation, and air conditioning (HVAC) systems within the context of a global SARS-CoV-2 epidemic

Ashraf Mimi Elsaid et al.

Summary: The COVID-19 pandemic has caused widespread devastation worldwide, altering human behavior and impacting the global economy. Air conditioning systems, particularly air filters, play a crucial role in preventing the spread of the virus, with researchers working towards improving their design to combat COVID-19 efficiently.

PROCESS SAFETY AND ENVIRONMENTAL PROTECTION (2021)

Article Green & Sustainable Science & Technology

Air Ventilation Performance of School Classrooms with Respect to the Installation Positions of Return Duct

Sungwan Son et al.

Summary: This study conducted three-dimensional numerical analysis to investigate the indoor airflow in elementary school classrooms, finding that floor return system can effectively reduce the risk of cross-infection among students.

SUSTAINABILITY (2021)

Review Thermodynamics

Airborne transmission of SARS-CoV-2 in indoor environments: A comprehensive review

Jialei Shen et al.

Summary: The COVID-19 pandemic has caused millions of deaths and great economic loss globally. There is substantial evidence supporting the airborne transmission of SARS-CoV-2, which can spread the disease over longer distances and times. Various indoor air quality control strategies have been analyzed for mitigating the airborne transmission risk, with a focus on both benefits and costs in designing control strategies.

SCIENCE AND TECHNOLOGY FOR THE BUILT ENVIRONMENT (2021)

Review Infectious Diseases

Review of the 2019 novel coronavirus (SARS-CoV-2) based on current evidence

Lisheng Wang et al.

INTERNATIONAL JOURNAL OF ANTIMICROBIAL AGENTS (2020)

Article Environmental Sciences

Estimation of airborne viral emission: Quanta emission rate of SARS-CoV-2 for infection risk assessment

G. Buonanno et al.

ENVIRONMENT INTERNATIONAL (2020)

Article Environmental Sciences

Airborne transmission of SARS-CoV-2: The world should face the reality

Lidia Morawska et al.

ENVIRONMENT INTERNATIONAL (2020)

Article Medicine, Research & Experimental

Airborne route and bad use of ventilation systems as non-negligible factors in SARS-CoV-2 transmission

G. Correia et al.

MEDICAL HYPOTHESES (2020)

Article Mechanics

Effects of ventilation on the indoor spread of COVID-19

Rajesh K. Bhagat et al.

JOURNAL OF FLUID MECHANICS (2020)

Review Environmental Sciences

Can Air-Conditioning Systems Contribute to the Spread of SARS/MERS/COVID-19 Infection? Insights from a Rapid Review of the Literature

Francesco Chirico et al.

INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH (2020)

Article Public, Environmental & Occupational Health

Decreased Influenza Activity During the COVID-19 Pandemic — United States, Australia, Chile, and South Africa, 2020

Sonja J. Olsen et al.

MMWR-MORBIDITY AND MORTALITY WEEKLY REPORT (2020)

Article Construction & Building Technology

The efficacy of social distance and ventilation effectiveness in preventing COVID-19 transmission

Chanjuan Sun et al.

SUSTAINABLE CITIES AND SOCIETY (2020)

Article Construction & Building Technology

Airborne transmission between room occupants during short-term events: Measurement and evaluation

Zhengtao Ai et al.

INDOOR AIR (2019)

Review Construction & Building Technology

A review of advanced air distribution methods - theory, practice, limitations and solutions

B. Yang et al.

ENERGY AND BUILDINGS (2019)

Article Virology

Transmission routes of respiratory viruses among humans

Jasmin S. Kutter et al.

CURRENT OPINION IN VIROLOGY (2018)

Review Respiratory System

Ventilation control for airborne transmission of human exhaled bio-aerosols in buildings

Hua Qian et al.

JOURNAL OF THORACIC DISEASE (2018)

Review Pediatrics

Influenza in Children

Virendra Kumar

INDIAN JOURNAL OF PEDIATRICS (2017)

Article Engineering, Multidisciplinary

Dynamic properties of fast gas concentration meter with nondispersive infrared detector

Wojciech Kierat et al.

MEASUREMENT (2017)

Article Construction & Building Technology

Human exhalation characterization with the aid of schlieren imaging technique

Chunwen Xu et al.

BUILDING AND ENVIRONMENT (2017)

Article Construction & Building Technology

Fifty years of CFD for room air distribution

Peter V. Nielsen

BUILDING AND ENVIRONMENT (2015)

Article Construction & Building Technology

A review of the performance of different ventilation and airflow distribution systems in buildings

Guangyu Cao et al.

BUILDING AND ENVIRONMENT (2014)

Article Construction & Building Technology

The risk of airborne cross-infection in a room with vertical low-velocity ventilation

I. Olmedo et al.

INDOOR AIR (2013)

Review Construction & Building Technology

Indoor aerosols: from personal exposure to risk assessment

L. Morawska et al.

INDOOR AIR (2013)

Correction Mathematical & Computational Biology

Statistical methods for assessing interchangeability of biosimilars (vol 32, pg 444, 2008)

Aijing Zhang

STATISTICS IN MEDICINE (2013)

Article Construction & Building Technology

Investigation into anti-airborne infection performance of stratum ventilation

Zhang Lin et al.

BUILDING AND ENVIRONMENT (2012)

Article Engineering, Chemical

Particle Image Velocimetry of Human Cough

Meg VanSciver et al.

AEROSOL SCIENCE AND TECHNOLOGY (2011)

Article Construction & Building Technology

Commemorating 20 years of Indoor Air CFD and ventilation research

Y. Li et al.

INDOOR AIR (2011)

Article Engineering, Chemical

Modeling the Fate of Expiratory Aerosols and the Associated Infection Risk in an Aircraft Cabin Environment

M. P. Wan et al.

AEROSOL SCIENCE AND TECHNOLOGY (2009)

Article Construction & Building Technology

Inhalation intake fraction of pollutants from episodic indoor emissions

William W. Nazaroff

BUILDING AND ENVIRONMENT (2008)

Article Immunology

Epidemiology of influenza

Arnold S. Monto

VACCINE (2008)

Article Environmental Sciences

Study of expiratory droplet dispersion and transport using a new Eulerian modeling approach

Alvin C. K. Lai et al.

ATMOSPHERIC ENVIRONMENT (2007)

Review Immunology

Review of aerosol transmission of influenza A virus

Raymond Tellier

EMERGING INFECTIOUS DISEASES (2006)

Article Physiology

Thermal manikin history and applications

I Holmér

EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY (2004)

Article Construction & Building Technology

Risk of indoor airborne infection transmission estimated from carbon dioxide concentration

SN Rudnick et al.

INDOOR AIR (2003)

Article Construction & Building Technology

Dispersal of exhaled air and personal exposure in displacement ventilated rooms

E Bjorn et al.

INDOOR AIR (2002)