Cabin ventilation system for a public transport vehicle

The system has a ventilation unit with distribution ducts (16, 17) arranged at base of air content part (V16). Each duct has an outer sheath (19) elongated and opened along its length such that air evacuated along the sheath is directed towards parts (V16A, V16B) to generate swirling airflows. Each duct has an inner diffuser (18) to homogeneously distribute the air along its length when recirculated air is supplied at its base. Independent claims are also included for the following: (A) a public transport vehicle with a cab interior comprising a ventilation system (B) a method for ventilating a cab interior of a public transport vehicle.