Cover Your Mouth! Coronavirus Study Suggest Cough Droplets Can Reach Farther Than 6 Feet

In the Physics of Fluids journal, researchers recently suggested that the mandated six-feet social distancing may not be enough for those experiencing coughing as a symptom of COVID-19.

“Although the exact transmission mechanism of SARS-CoV-2 remains unclear, it is generally agreed that the airborne transmission route cannot be dismissed,” their research states.

If you are shorter than the person coughing, you are at an even greater risk of contracting the virus.

“Young children may be at greater risk compared to adults based on the typical downward cough trajectory,” they wrote. “Teenagers and short adults are advised to maintain a social distance greater than 2 m (6 feet) from taller persons.”

In the simulation study, “scientists at Singapore’s Agency of Science, Technology, and Research used numerical models to simulate what the trajectory of droplets would be if a person suddenly coughs.”  when outside. Variables included “the size of the droplets, the heights of the two people in the simulation, wind speeds, air temperature, and humidity.”

From the study, there were four key takeaways referenced by the Atlanta Journal-Constitution:

1. Droplets less than 50 micrometers in diameter can remain airborne over long distances. At wind speeds of 2 meters per second, travel distances for droplet sizes 100 micrometers and 1000 micrometers are 21 feet and 4.25 feet, respectively.

2. Large droplets may travel more than 3.28 feet under windless conditions. The travel distance correlates well with the wind speed. For a 100 micrometer droplet, the travel distance increases from 2.62 feet without wind to 19.7 feet at a wind speed of 10 feet per second.

3. Social distancing is generally effective at reducing the droplet volume as well as the viral load deposited on a person nearby.

4. Droplet deposition on skin and clothes may not directly lead to infection. However, secondary transmission modes, including the face, mouth, or nose touching, need to be avoided. Hygiene measures such as the washing of hands and exposed surfaces are highly recommended.