The volume of air remaining in the lungs even after a forcible expiration is called as residual volume. Additional volume of air, a person can expire by a forcible expiration. This averages 1000 mL to 1100 mL is known as Expiratory Reserve Volume (ERV).
Additional volume of air, a person can inspire by a forcible inspiration. This averages 2500 mL to 3000 mL is known as Inspiratory Reserve Volume (IRV). Volume of air inspired or expired during a normal respiration. It is approx. 500 mL., i.e., a healthy man can inspire or expire approximately 6000 to 8000 mL of air per minute is known as tidal volume.