Reducing Radiation Exposure

At Mass General, radiation dose for CT scans are 30% to 95% lower than national averages. We customize each scan to achieve the lowest radiation dose possible.

We are constantly exposed to radiation from natural sources such as rocks, soil and the atmosphere. Americans receive about 3 millisieverts (mSv) of naturally occurring radiation annually. A mSv is a standard unit of radiation measurement.

Select an exam to find out how our radiation dose compares to the national average.

- 3 mSv is the average American's annual exposure to background radiation
- The mSv for exams at Mass General are estimates that represent the average dose based on population data
- National averages are from the National Radiology Data Registry maintained by the American College of Radiology



Radiation safety

Learn how Mass General Imaging works to increase patient safety by reducing radiation exposure.