Lung volumes
There are several different measures of lung volumes, some of which can be taken by Spirometry. They are;
1. Tidal Volume
The volume of air inspired and expired over the course of a normal breath. This is around 500 mls
2. Inspiratory Reserve Volume
The volume of air that can be inspired over and above that of a normal (tidal volume) breath. This is around 3100 mls
3. Expiratory Reserve Volume
The Volume of air that can be expired over and above that of a normal breath. This is around 1200 mls
4. Residual volume
The volume of air that is left in the lungs after maximal expiration; that is after the expiratory reserve volume. It is around 1200 mls but cannot be measured by spirometry.