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Radiation Protection

Radiation Terms and Units

Scientists measure radiation in different ways. Sometimes, they measure the dose that a person receives from a radioactive source, and sometimes they measure the amount of radioactivity in water, or in soil, or in the air.  Each measure describes a different aspect of radiation, and each has its own unit.

There are different but interrelated units for measuring radioactivity and its effects:

Use the Radiation Dose Calculator to estimate your yearly dose from sources of ionizing radiation.