NEW YORK (CBSNewYork) — A new study is out that looks into the safest way to ride in a car without spreading COVID-19.

As CBS2’s Natalie Duddridge reported Tuesday, since COVID, taxi drivers changed the number of riders they pick up.

“We used take four like passengers, two in the back, one in the front, but now we don’t take one in the front, just two in the back,” one driver said.

Car sharing services such as Uber and Lyft suspended carpooling features. Parents stopped picking up neighborhood kids and commuters stopped sharing rides.

CORONAVIRUS PANDEMIC

“The only person that gets in this car is my daughter,” said commuter Fernando Racalo.

“Anyone in my household I am of course fine with, but anyone who is out of my household … I just feel like it’s such an unnecessary risk,” said commuter Sophie Scott.

To help those who must ride-share, scientists at the University of Massachusetts studied airflow inside vehicles using a smoke visualization.

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“We look at these tiny particles motion. What we did was we released these particles from one of the occupants, and looked at how much of that gets to the other occupant,” said scientist Varghese Mathai.

Scientists confirmed what most of us already assume: When the heat is on and windows closed, the risk for transmission goes up. So the safest way to drive is with all the windows down. But in winter, when it’s cold, you can be almost as safe with just two specific windows down: The rear driver’s side and front passenger.

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“If the air comes in behind the driver and it kind of sweeps across the back of the car, and then goes past the passenger and out through the front window. And so it generates this predominant air flow that kind of clears the air,” said University of Massachusetts scientist Kenny Breuer.

As for taxis, researchers say clear acrylic barriers inside cabs do help stop spread. But still, you should always crack a window.

The CDC recommends if you’re road tripping with family this holiday, it should be with people from the same household, with all windows down and masks up.

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