Radiobiology > Background > Medical Radiation in Context
Medical Radiation in Context – Background Exposure
Diagnostic medical imaging contributes approximately 11% of the annual, per capita U.S. whole-body radiation exposure, which averages about 3.2 mSv (320 mRem) total (NCRP Report No. 93).
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Natural sources of background radiation: cosmic rays (79% protons, 20% alpha particles, 1% heavy nuclei) and naturally occurring isotope decay |
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