ArticleJournal of the Royal Society, Interface2009
A schlieren optical study of the human cough with and without wearing masks for aerosol infection control.
Article in Journal of the Royal Society, Interface, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 151 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
151 citing papers in PubMed, 2 syntheses or guidelines pooled it, 318 citations in OpenAlex.
- Aerosol-generating behaviours in speech pathology clinical practice: A systematic literature review.PloS one · 2021Pooled it
- Pooled it
- Article
- Fluid dynamical pathways of airborne transmission while waiting in a line.Science advances · 2025Article
- Creating respiratory pathogen-free environments in healthcare and nursing-care settings: a comprehensive review.GeroScience · 2025Review
- An integrated airborne transmission risk assessment model for respiratory viruses: short- and long-range contributions.Journal of the Royal Society, Interface · 2025Article
- Population Behavior Regarding the Use of Face Masks to Prevent the Transmission of Respiratory Infections: Lessons to Be Learned from the COVID-19 Pandemic.International journal of environmental research and public health · 2025Article
- 3D modelling and simulation of thermal effects and dispersion of particles carrying infectious respiratory agents in a railway transport coach.Scientific reports · 2025Article
- Identifying the effectiveness of face mask in a large population with a network-based fluid model.PloS one · 2025Article
- Development of Technology for Providing Antimicrobial Properties to Medical Disposable Masks.Polymers · 2024Article
- Droplet Micro-Sensor and Detection of Respiratory Droplet Transmission.Advanced science (Weinheim, Baden-Wurttemberg, Germany) · 2024Article
- Article
- Understanding lifetime and dispersion of cough-emitted droplets in air.Indoor + built environment : the journal of the International Society of the Built Environment · 2023Article
- The Effectiveness of a Novel Air-Barrier Device for Aerosol Reduction in a Dental Environment: Computational Fluid Dynamics Simulation.Bioengineering (Basel, Switzerland) · 2023Article
- Characterizing Aerosol Generating Procedures With Background Oriented Schlieren.Journal of biomechanical engineering · 2023Article
- 3D modelling and simulation of the impact of wearing a mask on the dispersion of particles carrying the SARS-CoV-2 virus in a railway transport coach.Scientific reports · 2023Article
- Face masks for respiratory viral illness prevention in healthcare settings: a concise systemic review and meta-analysis.Iranian journal of microbiology · 2023Review
- Perceptions, Knowledge, and Experiences of Using Face Masks among Egyptian Healthcare Workers during the COVID-19 Pandemic: A Cross-Sectional Study.Healthcare (Basel, Switzerland) · 2023Article
- Article
- The Spread of Exhaled Air and Aerosols during Physical Exercise.Journal of clinical medicine · 2023Article
91 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
4 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Various infectious agents are known to be transmitted naturally via respiratory aerosols produced by infected patients. Such aerosols may be produced during normal activities by breathing, talking, coughing and sneezing. The schlieren optical method, previously applied mostly in engineering and physics, can be effectively used here to visualize airflows around human subjects in such indoor situations, non-intrusively and without the need for either tracer gas or airborne particles. It accomplishes this by rendering visible the optical phase gradients owing to real-time changes in air temperature. In this study, schlieren video records are obtained of human volunteers coughing with and without wearing standard surgical and N95 masks. The object is to characterize the exhaled airflows and evaluate the effect of these commonly used masks on the fluid-dynamic mechanisms that spread infection by coughing. Further, a high-speed schlieren video of a single cough is analysed by a computerized method of tracking individual turbulent eddies, demonstrating the non-intrusive velocimetry of the expelled airflow. Results show that human coughing projects a rapid turbulent jet into the surrounding air, but that wearing a surgical or N95 mask thwarts this natural mechanism of transmitting airborne infection, either by blocking the formation of the jet (N95 mask), or by redirecting it in a less harmful direction (surgical mask).
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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.