What does it do? When driving a car, the driver is exposed to two or three times more pollution than a pedestrian. In fact, the car's ventilation system is in almost direct contact with the exhausts of the vehicles in front and concentrates dust, pollen and soot. Especially for drivers/passengers with allergies this often causes problems. Furthermore, the cabin filter effectively reduces the film of dirt on the windscreen, thus improving night vision. Therefore all major car manufacturers currently produce cars with cabin air filters. To guarantee that the air in the interior is pure at all times, the filter needs to be replaced regularly. When the manufacturer recommends replacement or as soon as the build-up of particles of dust, soot and pollen leads to a pressure drop, incompatible with acceptable performance of the vehicle’s ventilation system. The main signs of clogging up or saturation are: