Pulmonary Function test is a diagnostic and management tool for assessing the functional status of lungs of an individual. The primary function of PFT is to identify the severity of pulmonary impairment. This test is performed on a computerised machine wherein the patient takes a deep breath and blows out into the mouth piece of the machine and the machine calculates various parameters to assess the functional status of lungs. It is a safe procedure and is done by respiratory therapist.