Why keeping car air recirculation on too long may affect driver focus

Drivers often use the air recirculation button, usually marked by a curved arrow, to block outside odors or speed up temperature changes inside the vehicle. While useful, keeping this mode active for too long can reduce the quality of the air inside the cabin. How Air Recirculation Works During normal operation, a vehicle's climate control system draws fresh air from outside, filters it and pushes it into the cabin. Activating recirculation closes the external air intake, forcing the system to circulate the existing cabin air repeatedly. While this prevents outside odors and pollutants from entering, prolonged use also reduces the supply of fresh air.