ArticleScientific reports2021
Expiratory aerosol particle escape from surgical masks due to imperfect sealing.
Article in Scientific reports, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers, 2 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
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.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
21 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Masks and respirators for prevention of respiratory infections: a state of the science review.Clinical microbiology reviews · 2024Pooled it
- TFOS lifestyle: Impact of societal challenges on the ocular surface.The ocular surface · 2023Pooled it
- Assessing the generation and dispersal of respiratory particles using upper respiratory commensal bacteria as index organisms for respiratory pathogens.Scientific reports · 2025Article
- Effects of Wind Speed on Water Uptake, Phase State, and Viscosity of Sea Spray Aerosols.ACS earth & space chemistry · 2025Article
- Effects of Wind Speed on Size-Dependent Morphology and Composition of Sea Spray Aerosols.ACS earth & space chemistry · 2024Article
- Article
- Environmental Dissemination of SARS-CoV-2 in a University Hospital during the COVID-19 5th Wave Delta Variant Peak in Castile-León, Spain.International journal of environmental research and public health · 2023Article
- Effects of Atmospheric Aging Processes on Nascent Sea Spray Aerosol Physicochemical Properties.ACS earth & space chemistry · 2022Article
- Risk assessment for long- and short-range airborne transmission of SARS-CoV-2, indoors and outdoors.PNAS nexus · 2022Article
- Experimental and numerical investigation on aerosols emission in musical practice and efficiency of reduction means.Journal of aerosol science · 2022Article
- A critical review on the role of leakages in the facemask protection against SARS-CoV-2 infection with consideration of vaccination and virus variants.Indoor air · 2022Review
- Quantifying the Risk to Health Care Workers of Cough as an Aerosol Generating Event in an Ambulance Setting: A Research Report.Prehospital and disaster medicine · 2022Review
- Evaluation of Respiratory Particle Emission during Otorhinolaryngological Procedures in the Context of the SARS-CoV-2 Pandemic.Diagnostics (Basel, Switzerland) · 2022Article
- A Simple Method to Quantify Outward Leakage of Medical Face Masks and Barrier Face Coverings: Implication for the Overall Filtration Efficiency.International journal of environmental research and public health · 2022Article
- Will the COVID-19 pandemic end with the Delta and Omicron variants?Environmental chemistry letters · 2022Article
- Society organization, not pathogenic viruses, is the fundamental cause of pandemics.Environmental chemistry letters · 2022Article
- International consensus on lung function testing during the COVID-19 pandemic and beyond.ERJ open research · 2022Review
- A comparison of respiratory particle emission rates at rest and while speaking or exercising.Communications medicine · 2022Article
- SARS-CoV-2 Aerosol Transmission Indoors: A Closer Look at Viral Load, Infectivity, the Effectiveness of Preventive Measures and a Simple Approach for Practical Recommendations.International journal of environmental research and public health · 2021Article
- Maintaining mask momentum in transplant recipients.Transplant infectious disease : an official journal of the Transplantation Society · 2021Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors.
Funding
Abstract
Wearing surgical masks or other similar face coverings can reduce the emission of expiratory particles produced via breathing, talking, coughing, or sneezing. Although it is well established that some fraction of the expiratory airflow leaks around the edges of the mask, it is unclear how these leakage airflows affect the overall efficiency with which masks block emission of expiratory aerosol particles. Here, we show experimentally that the aerosol particle concentrations in the leakage airflows around a surgical mask are reduced compared to no mask wearing, with the magnitude of reduction dependent on the direction of escape (out the top, the sides, or the bottom). Because the actual leakage flowrate in each direction is difficult to measure, we use a Monte Carlo approach to estimate flow-corrected particle emission rates for particles having diameters in the range 0.5-20 μm. in all orientations. From these, we derive a flow-weighted overall number-based particle removal efficiency for the mask. The overall mask efficiency, accounting both for air that passes through the mask and for leakage flows, is reduced compared to the through-mask filtration efficiency, from 93 to 70% for talking, but from only 94-90% for coughing. These results demonstrate that leakage flows due to imperfect sealing do decrease mask efficiencies for reducing emission of expiratory particles, but even with such leakage surgical masks provide substantial control.
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Registered trials
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.