Dr. Rai has worked at various apex institutes of Armed Forces (Army Hospital R & R Delhi, Kolkata, Ranchi and Cardio-Thoracic Centre of Armed Forces Medical College Pune) as Pulmonologist, and was PG Lecturer and Examiner for MUHS and West Bengal University of Health Sciences with more than 25 years of teaching experience. He is a member of Editorial Board of Indian Journal of Tuberculosis and referee for Medical Journal Armed Forces India and Lung India.