HEPA filter are only in the Medical center. From Princess website...
How have you improved the onboard HVAC system?
Where possible, we’ve increased outside air to the maximum practical level for each HVAC unit.
HVAC units have been upgraded with F7 (MERV 13) filters, and some units also have the latest generation ultraviolet light (UVC/UVGI) treatment systems to facilitate high quality recirculated air, where possible within design limitations.
The Medical Center has HEPA filtration and is maintained under negative pressure, which means the ventilation system removes more air than it allows into the room.
HEPA filter are only in the Medical center. From Princess website... How have you improved the onboard HVAC system? Where possible, we’ve increased outside air to the maximum practical level for each HVAC unit. HVAC units have been upgraded with F7 (MERV 13) filters, and some units also have the latest generation ultraviolet light (UVC/UVGI) treatment systems to facilitate high quality recirculated air, where possible within design limitations. The Medical Center has HEPA filtration and is maintained under negative pressure, which means the ventilation system removes more air than it allows into the room.