What are typical adult radiation doses from common imaging exams? Each exam is compared with the length of time it would take for you to receive the same dose as “background radiation” — the type that comes from soil, rocks, food and the atmosphere. It enters your body in the course of everyday life. This content supports the care you receive from your healthcare team. It does not replace medical care or advice. Talk to your doctor or others on your healthcare team before you start any new treatment. Content goes through routine review by experts on our staff.