Should Car Anti-Fog Spray Be Applied Inside or Outside?

[DelClayton]

Car anti-fog spray is generally applied inside. Fogging in cars occurs due to the temperature difference between the inside and outside of the vehicle: In winter, when the outside temperature is low and the inside temperature is high, the water vapor inside the car condenses into tiny droplets upon contact with the cold glass, forming a layer of fog. On rainy or foggy days, the high humidity in the air also makes it easy for a layer of fog to form on the car windows. When the windshield or rearview mirror fogs up, it severely obstructs the driver's vision, posing a safety hazard. The function of car anti-fog spray: Spraying a small amount of anti-fog agent on the car glass and then wiping it clean can remove dirt and stains from the window. This not only cleans the glass but also forms a transparent protective film that prevents water vapor from condensing into fog on the glass, making it particularly useful in cold winters.