1-17. AIR CAPACITY OF THE LUNGS
The amount of air in the lung of a man of average size who is resting is about 3
liters. When the man breathes in (inspiration or inhalation), he pulls in about 500
milliliters of air. When he deliberately breathes in (forced maximum inspiration), the
amount of air in the lung rises to about 6 liters. When the same man forces the
maximum amount of air out of the lung, the volume of air is down to about 1 liter. Here
are important facts about volume of air and the lungs:
NOTE: 1 milliliter (ml) = 1 cubic centimeter (cc).
a. The total capacity of the lungs is about 6,000cc (maximum).
b. Tidal air volume is the amount of air inhaled or exhaled with each breath,
whether the body is at rest or engaged in an activity. For the average adult male who is
resting, the tidal volume is about 500cc of air.
c. Reserve air is air in the lungs that can be exhaled after normal exhalation.
The amount of this air is about 1,500cc.
d. Residual air is air that is in the lungs after normal, forceful expiration (about
e. Vital capacity (usually 4,800cc) is the volume of air that can be expelled after