Recirculation of air within a vehicle is an excellent approach to limit particle pollution and enhance air conditioner cooling efficiency. Nevertheless, prolonged use of recirculation air within a vehicle may result in high accumulation of carbon dioxide (CO2) in the vehicle�s cabin due to human exhalation and the lack of fresh air. On the other hand, allowing outside air to enter into the cabin would expose the passengers to roadway contaminants. Since the contaminants in outdoor air may not be noticeable by humans, the vehicle drivers would not be able to know if the air quality in the car cabin is a healthy one. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.