Which is better for breathing quality air in your car, the recycle button or letting new air in through the vents? I’d think that recycle is better when you’re in the town and getting new air is better when you’re in the country as long as you aren’t behind another vehicle.
At work we had just purchased a new CO2 meter. It is used to test ventilation in building to be sure enough fresh air is being brought in. We were traveling in his company van and turned it on to see what kind of reading we would get. Because of the heat and we were driving in rush hour traffic we had the recycle button on. When I turned on the meter on and it went straight into the red zone.
WE turned the recycle off and opened the windows to check the new meter. The meter went down into the green. Rolled the windows with the recycle off. The meter stayed in the green. Hit the recycle button and the meter started climb in a short time. We both did not believe the readings so we repeated the test. I now seldom close the recycle when traveling.
We were on the 880 in San Jose traveling about 3 to 5 miles per hour. 4 lanes both ways.
I usually only use the recycle when I’m first warming up or cooling down the car. Or in particularly dusty/smelly areas.
If the road ahead is clear, I open the vents. But have to be quick with the button when I see a vehicle ahead of me belching noxious fumes.
Air ‘quality’ is an almost completely subjective thing. The biggest thing the recirculate vs fresh air setting will effect is the humidity. Although they’ve finally stopped pushing them, for the last 20 years or so car dealerships and quick oil change places made a cottage industry out of trying to up-sell customers on ridiculously expensive and practically useless ‘cabin air filters’. They are a scam as bad as bottled water…