Covid study: How to avoid catching virus in a shared car - BBC News
▻https://www.bbc.com/news/uk-wales-58202468
For driving below 30mph (48kph), opening all four windows is most beneficial.
But on faster roads, opening two on a diagonal can have an even bigger impact.
We found that the increased difference in air pressure at high speeds meant that the diagonal opening (eg a front window on the right and a rear window on the left) created a very strong targeted tunnel effect, which was even more efficient at dispersing particles than having all four windows open," said Prof Li.
“The process is so effective that it’s only necessary to do it for 10 seconds at a time, every five to 10 minutes, or whenever somebody coughs or sneezes.”
Prof Li said having the windows open constantly would create its own risks from exhaust fumes and air pollution outside the vehicle, which could potentially be more serious than Covid.
The team’s research also discovered that sitting in the front seats was far safer than being in the back, owing to the prevailing direction of the airflow through the car.
If passengers do have to sit in the rear, Prof Li recommended they sit in the opposite seat to where the window is being opened.