Ask Dr KK:How is CT radiation comparable to X ray Chest?

The dose from a single abdominal CT scan is comparable to the collective dose of 400 chest x-rays or natural background radiation for three years. 

About the author: Dr K K Aggarwal is Padmashri and Dr B C Roy National Awardee, President Heart Care Foundation of India, Dean Board of Medical Education Moolchand Medcity, Sr. Physician & Cardiologist, Visiting professor Clinical Research DIPSAR, Past President Delhi Medical Association, Past Academic and Research Wing Head IMA, Chairman Ethics Committee Delhi Medical Council.