ArticleProceedings of the National Academy of Sciences of the United States of America2021
A guideline to limit indoor airborne transmission of COVID-19.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 183 papers, 3 of them syntheses that pooled it.
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
183 citing papers in PubMed, 3 syntheses or guidelines pooled it.
- Managing infectious aerosols to counter engineered pandemics: Current recommendations and future research.Risk analysis : an official publication of the Society for Risk Analysis · 2025Guideline
- The Risk of Aircraft-Acquired SARS-CoV-2 Transmission during Commercial Flights: A Systematic Review.International journal of environmental research and public health · 2024Pooled it
- Learning from the covid-19 outbreaks in long-term care facilities: a systematic review.BMC geriatrics · 2023Pooled it
- The effect of smaller classes on infection-related school absence: evidence from the Project STAR randomized controlled trial.BMC public health · 2024Trial
- Monitors to improve indoor air carbon dioxide concentrations in the hospital: A randomized crossover trial.The Science of the total environment · 2022Trial
- Uneven Protection at Work During COVID-19: Union Voice, Paid Sick Leave and Safety Regimes in Ontario.Labor studies journal · 2026Article
- Beyond Infection-Indoor Airborne Pathogens as Contributors to Respiratory Inflammation and Immune Dysregulation: A Narrative Review.Pathogens (Basel, Switzerland) · 2026Review
- The Wells-Riley Model Revisited II: Parameter Uncertainty and Population Heterogeneity.Risk analysis : an official publication of the Society for Risk Analysis · 2026Article
- Implications for distancing measures on in-person school and work attendance from Italian post-pandemic social contact data.Communications medicine · 2026Article
- Heterogeneity of Airborne Virus Transmission in the Built Environment: A Narrative Review.Pathogens & immunity · 2026Review
- Electrospun biodegradable polycaprolactone filter media for filtering facepiece respirators.Journal of materials science. Polymers · 2026Article
- SARS-CoV-2 Surface Contamination and Viable Virus in High-Ventilation Single Rooms: Implications for Fomite Transmission.Juntendo medical journal · 2026Article
- Timing and type of personal protective equipment adherence lapses in pediatric trauma resuscitation: A retrospective video study.American journal of infection control · 2025Article
- Review
- Article
- Web-based real-time risk assessment of coronavirus disease 2019 infection in schools and social dining settings.New microbes and new infections · 2025Article
- Methodology of Epidemic Risk Analysis in the Naval Military.International journal of environmental research and public health · 2025Review
- Viral Transmission in Sea Food Systems: Strategies for Control and Emerging Challenges.Foods (Basel, Switzerland) · 2025Review
- Pathogenesis and transmission of SARS-CoV-2 D614G, Alpha, Gamma, Delta, and Omicron variants in golden hamsters.Npj viruses · 2025Article
- CO2 and aerosol concentration during manual and mechanical chest compression while cardiopulmonary resuscitation.Medicine · 2025Article
123 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
2 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The current revival of the American economy is being predicated on social distancing, specifically the Six-Foot Rule, a guideline that offers little protection from pathogen-bearing aerosol droplets sufficiently small to be continuously mixed through an indoor space. The importance of airborne transmission of COVID-19 is now widely recognized. While tools for risk assessment have recently been developed, no safety guideline has been proposed to protect against it. We here build on models of airborne disease transmission in order to derive an indoor safety guideline that would impose an upper bound on the "cumulative exposure time," the product of the number of occupants and their time in an enclosed space. We demonstrate how this bound depends on the rates of ventilation and air filtration, dimensions of the room, breathing rate, respiratory activity and face mask use of its occupants, and infectiousness of the respiratory aerosols. By synthesizing available data from the best-characterized indoor spreading events with respiratory drop size distributions, we estimate an infectious dose on the order of 10 aerosol-borne virions. The new virus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) is thus inferred to be an order of magnitude more infectious than its forerunner (SARS-CoV), consistent with the pandemic status achieved by COVID-19. Case studies are presented for classrooms and nursing homes, and a spreadsheet and online app are provided to facilitate use of our guideline. Implications for contact tracing and quarantining are considered, and appropriate caveats enumerated. Particular consideration is given to respiratory jets, which may substantially elevate risk when face masks are not worn.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.