Cabin air is supplied through overhead ventilation outlets and flows downward through the occupied space. Air is then extracted near the floor and routed through the aircraft’s environmental control and recirculation system before being redistributed.

A portion of cabin air is recirculated as part of the aircraft’s environmental control system. Before reuse, this air passes through a filtration section and is then combined with outside supply air prior to returning to the cabin.

Cabin air filters are installed within the recirculation ducting of the aircraft ventilation system, upstream of the point where recirculated air is mixed with outside air.

Cabin air is refreshed multiple times per hour through a controlled combination of outside supply air and filtered recirculated air managed by the environmental control system.

Filtration functions as one component of the overall ventilation and environmental control architecture, supporting continuous airflow management throughout all phases of flight.