Exempt Quantities of Radioactive Material

The Nuclear Regulatory Commission (NRC) and Wisconsin Department of Health Services Radiation Protection Section (DHS) have determined that exempt quantity sources, which are radioactive sources containing small amounts of radioactivity and used under certain conditions, do not represent a significant health hazard.  These exempt quantity sources of radioactive material are typically small, sealed sources used for meter checks or instructional labs; however, they can be produced in many other forms if the quantity is sufficiently low.

Possession and Storage

The possession and use of this material does not require the user or institution to hold a radioactive material license from the NRC or DHS.  Therefore, a license is not required to order these sources of radioactive material from suppliers.  Exempt sources of radioactive material may be stored without special considerations.  Care should be made to ensure it is differentiated from licensed material to eliminate confusion by untrained individuals.  Simply placing the material in a bag labeled “Exempt Radioactive Material” would be sufficient.  The Office of Radiation Safety (ORS) has produced an Exempt Material Notification Card which can be provided to users to keep with their exempt radioactive material as a more official means of differentiation.

Radiological Hazard

The NRC and DHS have deemed exempt quantity sources to not represent a significant health hazard.  However, they still emit radiation.  With all radioactive material, the hazard is reduced using administrative and engineering controls such as time, distance, and shielding.  Reducing one’s time in the presence of radioactive material, increasing one’s distance from the source of radiation, or installing shielding between oneself and the source of radiation are all methods to reduce the already low health hazard.  However, it should be noted that these precautions are not required for radioactive materials deemed exempt.


Please contact the ORS to dispose of any type or amount of exempt quantity radioactive material.  This will help ensure that there is no confusion between the unlicensed exempt radioactive material and the possibly hazardous licensed radioactive material, both of which are present on our campus.

More Information

For more information on the radiological hazards, please contact the ORS at RadiationSafety@wisc.edu.  Users are welcome to take the Radiation Safety 101: Radiation Safety for Radiation Workers training course if they would like further information and training on radioactive material use and storage even if only for exempt material.

Please see the ORS website for more information – https://ehs.wisc.edu/labs-research/radiation-safety/.