This rulemaking would revise the NRC's regulations to update the requirements to allow for the inclusion of emerging medical technologies. The purpose of the rulemaking is primarily to bring established modalities currently licensed as emerging medical technologies and allow them to be licensed under other subsections of the regulations to improve licensing consistency across the country. The regulated entities affected would include all NRC, Agreement State, and Master Materials License medical licensees and permittees using microspheres and gamma stereotactic radiosurgery. This rulemaking will also add requirements to address calibration and dosage measurement for rubidium-82 generators.