This is the safest way to travel during the pandemic

Although health officials advise against domestic travel right now, many have made a point to publish and update guidance instructing the public on how to do so safely.

The latest was featured in the journal, Science Advances. In it, researchers from the University of Massachusetts Amherst and Brown University determined that in order to reduce one’s risk of coronavirus transmission while transporting passengers, parties should travel with the windows farthest from where they are seated down. This is recommended for those occupying a vehicle with family, friends, and ride-share services.

“Transmission of highly infectious respiratory diseases, including SARS-CoV-2, is facilitated by the transport of exhaled droplets and aerosols that can remain suspended in air for extended periods of time. A passenger car cabin represents one such situation with an elevated risk of pathogen transmission,” the authors wrote in the new paper.

“Here, we present results from numerical simulations to assess how the in-cabin microclimate of a car can potentially spread pathogenic species between occupants for a variety of open and closed window configurations. We estimate relative concentrations and residence times of a noninteracting, passive scalar—a proxy for infectious particles—being advected and diffused by turbulent airflows inside the cabin.

The authors used a simulated car (modeled after a Toyota Prius) that held two people inside—with the second passenger sitting in the back seat on the opposite side from the driver.

This particular seating arrangement was initially employed because it was theorized to be the safest way to travel, as it allows the maximum amount of physical distance between two people sharing a cabin.

The computer model-simulated airflow around and inside the model car moving at 50 miles per hour, in addition to the movement of viral particles coming from both the driver and the passenger at varying concentrations.

The researchers subsequently assessed air changes every hour in six different windows-open-hypotheticals with the air-conditioning on in all of them.

A review of the results indicated that open windows facilitate airflow patterns that reduce the concentration of airborne viral debris disbursed between a driver and a single passenger. This worked much better than standard car ventilation systems.

The worst thing a driver can do, according to the researchers (with respect to coronavirus transmission risk) is operate their vehicle with the windows up and the air conditioning or heat on.

“An airflow pattern that travels across the cabin, farthest from the occupants, can potentially reduce the transmission risk. Our findings reveal the complex fluid dynamics during everyday commutes and nonintuitive ways in which open windows can either increase or suppress airborne transmission,” the author continued.

The Centers for Disease Control and Prevention provide additional materials about safe ways to choreograph extended ventures while outbreaks are appearing around the country. Be sure to check them out if you plan on hopping in your car in the near future.

“Making stops along the way for gas, food, or bathroom breaks can put you and your traveling companions in close contact with other people and frequently touched surfaces. Use disinfecting wipes on handles and buttons at the gas pumps before you touch them (if available),” the agency reports.

“After fueling, use a hand sanitizer with at least 60% alcohol. When you get to your destination, wash your hands with soap and water for at least 20 seconds. The safest option is to bring your own food. If you don’t bring your own food, use drive-through, delivery, take-out, and curbside pick-up options.”