Vital capacity

Forced Vital capacity


Force vital capacity is the maximum volume of air that a person can exhale after maximum inhalation. It can also be the maximum volume of air that a person can inhale after maximum exhalation.

A person's vital capacity can be measured by a Spirometers, Diagnostic which can be a wet or regular spirometer. In combination with other physiological measurements, the vital capacity can help make a diagnosis of underlying lung disease. The unit that is used to determine this vital capacity is milliliters.

Vital capacity is the maximum amount of air a person can expel from the lungs after first filling the lungs to their maximum extent and then expiring to the maximum extent. It equals the inspiration reserve volume plus the tidal volume plus the expiratory reserve volume.[1][2]



  1. Vital Capacity". Family Practice Notebook.
  2. Pratt, Joseph H. (1922). "Long-continued observations on the vital capacity in health and in heart disease". Transactions of the Association of American Physicians (W. J. Dornan, Incorporated) 37: 182–197.