Frequent Questions

How much radiation am I exposed to when I have a CT scan?

The total radiation exposure during a CT scan depends on the region of the body under examination. A CT scan may expose the patient to the radiation equivalent of 100-800 chest x-rays. Some examples of CT scans and approximate exposures are:

Head CT: 2.0 mSv (200 mrem)

Chest CT: 8.0 mSv (800 mrem)

Abdomen CT: 10 mSv (1,000 mrem)

Pelvis CT: 10 mSv (1,000 mrem)

Source: National Council on Radiation Protection & Measurements (NCRP), Report No. 160

Don’t know what mSv or mrem means? See EPA’s Radiation Terms and Units webpage.

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