About Air Circulation in Airplanes

Cabin air is renewed with fresh air every 2-3 minutes.


Fresh external air constantly replaces the cabin air every 2-3 minutes.


Modern aircraft are fitted with highly proficient air filters* keeping the cabin air clean at all times.

  • High-Efficiency Particulate Air (HEPA) filters are 99.97% effective at removing virus, bacteria, and fungi measuring 0.3μm in diameter, including the Coronavirus.


Air in a cabin flows from top to bottom and is fully renewed.

Flow of the air using HEPA filter image

  1. The aircraft receives external air through the engine
    *The Boeing 787 uses electric compressors to feed external air directly into its air-conditioning system, rather than from the engine.
  2. The air-conditioning system adjusts the compressed air to an appropriate temperature and supplies the clean air throughout the cabin.
  3. The differential pressure will push the air inside the cabin toward the belly of the aircraft and is discharged from the cabin pressure control valve.
  4. Increased airflow by cleaning a portion of the air flowing under the floor with a HEPA filter.

January 13, 2023

Japan Airlines