Asthma is a chronic inflammatory condition marked by attacks of spasm in the airways. It leads to production of thick mucus and difficulty in breathing. Genetically predisposed people may experience an acute attack on exposure of certain environmental triggers like-animal dander (fur of pets), pollen, dust mites, respiratory infections, air pollution, weather or temperature changes and cigarette smoke. The spirometry (PFT- Pulmonary function test) helps to diagnose asthma and assess its severity.