- Lowering all four car windows is the best way to decrease the risk of passing on or contracting infectious diseases
- Keeping all four windows closed, even with the aircon on increases the risk of infection
- Choosing the correct seat and window makes a huge difference
A new study has found that the safest way for two people to lower the risk of transmitting Covid-19 while travelling in a car, is with all four windows down and the passenger seated as far as possible from the driver – in the rear seat and on the opposite side to the driver.
The study by research hub Science Advances tested scenarios where a driver or passengers are most likely to be at risk of transmitting or catching highly infectious respiratory diseases, like Covid-19 or influenza.
The vehicle that was used in the test was a sedan that is typically used by e-hailing services in South Africa. The study results do not apply to trucks, trains, minibus taxis and buses.
Three better than two
Researchers investigated the risk of transmission with all four windows up – as well as four other scenarios with either one or two windows closed.
The risk of droplet transmission was highest when all four windows were closed and the car’s air conditioning system was being used.
The findings also show that travelling with three windows open was much better than two. But the study also revealed that choosing the correct windows to be open or closed played a role in the risk of transmission.
Closing the window where the person who is not infected is sitting, involves the lowest risk after the option of all the windows being open.
"These results will have a strong bearing on infection mitigation measures for the hundreds of millions of people driving in passenger cars and taxis worldwide, and potentially yield to safer and lower-risk approaches to personal transportation,” the authors say in a press release.
Public transport guidelines in SA
According to the Uber app services, passengers should sit at the back in order to lower the risk of transmission. However, the e-hailing service does not advise passenger on which side of the car they should be seated.
The study recommends that it should be on the opposite side of the driver.
Everyone should wear a mask to lower the probability of spreading the virus. In government guidelines, minibus taxis and trains should have the windows open for good ventilation in order to decrease the chances of passing on the virus to the next person.