The NRC is modernizing nrc.gov with an updated design and improved navigation to enhance usability. We are committed to a smooth transition and will work to minimize any disruption. The site may be briefly unavailable at times during launch. Thank you for your patience.
Biological half-life
The time required for a biological system, such as that of a human, to eliminate, by natural processes, half of the amount of a substance (such as a radioactive material) that has entered it.
Page Last Reviewed/Updated Tuesday, March 09, 2021
Page Last Reviewed/Updated Tuesday, March 09, 2021