This Old Photo Technique Shows How Masks Help Prevent the Spread of COVID-19

Advanced imaging company LaVision has released a new video that shows just how effective a face mask can be at preventing the spread of infections like COVID-19. The video lends visual support to the CDC’s recent recommendation that everyone wear a mask in any situation where it is difficult to maintain social distance.

The video uses an age old photographic technique called “Schlieren” imaging. We’ve previously featured Schlieren imaging to show supersonic shockwaves, sound waves, and even heat. Basically, anything the causes the displacement of air can be visualized in this way, and you don’t even need expensive equipment to do it.

As evidence mounts that the novel coronavirus can spread from person to person in tiny droplets (AKA aerosols) that can hang in the air much longer than the large droplets expelled when coughing or sneezing, visualizations like this help to explain why the CDC is now recommending that all people wear cloth face masks whenever they will be in a situation where social distance is hard to maintain, such as grocery stores or a trip to the pharmacy.

Schlieren imaging shows the airflow produced by simply speaking with (right) and without (left) a face mask.

“The primary way of person-to-person corona virus transmission is via aerosols or small droplets created by breathing, sneezing or coughing,” explains the video’s description. “The reach of exhaled air can be effectively reduced using a face mask as shown in the video.”

While the technique used in the video above is not quite as advanced or scientifically informative as this high-sensitivity footage of microdroplets captured by Japan’s NHK, both demonstrations use imaging to highlight the importance and effectiveness of wearing masks to help stop the community spread of a virus like SARS-CoV-2.

Check out the short demo above to see for yourself.

(via Fstoppers)