Respiratory Volumes/Capacities

Tidal Volume (V_t)

amount of air that moves in/out of your lungs during a single respiratory cycle @ rest (during normal quiet breathing)

Inspiratory Reserve Volume (IRV)

amount of air you can breathe in BEYOND tidal volume

Expiratory Reserve Volume (ERV)

amount of air you can EXHALE BEYOND tidal volume

Residual Volume

amount of air left in your lungs after maximal exhalation (INCLUDES MINIMAL VOLUME)

Minimal Volume

amount of air in lungs if they collapsed (not measurable in a healthy person)

Inspiratory Capacity

tidal volume + inspiratory reserve

Vital Capacity

maximum amount of air you can move in + out of your lungs per cycle (deep inhale/exhale); Expiratory Reserve Volume (ERV) + Tidal Volume (V_t) + Inspiratory Reserve Volume (IRV)

Functional Residual Capacity (FRC)

Expiratory Reserve Volume (ERV) + Residual Volume (RV); amount of air in lungs after a complete quiet cycle

Total Lung Capacity

Vital Capacity + residual volume; total volume of lungs ~ 6000 mL in males + 4200 mL in females