Lung Capacity:

  • about 500cm3 of air enters the lungs under each normal and quiet breathing cycle
  • same amount of air lungs while breathing out
  • this volume is known as tidal air
  • additional volume of air taken in on top of tidal air - during deep breath - is known as complemental air. (1500cm3)
  • supplemental air (1500cm3) is the amount of air forced out after normal expiration
  • vital capacity of lung 3500-4000 cm3 is the amount of air one can take by taking in the deepest breath
  • residual air the amount of air left in the lungs no matter how hard one tries to force out (1500cm3)

vital air = tidal air + complemental air + supplemental air.