Related Experiment Video
Updated: Aug 13, 2025

Laser-heating and Radiance Spectrometry for the Study of Nuclear Materials in Conditions Simulating a Nuclear Power Plant Accident
Published on: December 14, 2017
Modification in Applying Appendix D of 40 CFR Part 61 to Heated Solid Radionuclide Materials With High Melting and
Linda L Smith, William Bill L McCarter1, J Matthew Barnett2
1Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6113.
Abstract:
Appendix D of Title 40 Part 61 of the US Code of Federal Regulations (CFR) provides a procedure that US Department of Energy (US DOE) facility owners and operators can use to estimate radionuclide emissions to the atmosphere for dose calculations instead of measuring emissions for minor sources under the 40 CFR Part 61, Subpart H, National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities, regulation. The procedure assumes that any radioactive material heated above 100 °C is completely vaporized and emitted to the atmosphere. In 1991, the US DOE Oak Ridge Reservation (ORR) requested approval to use different release fractions (RFs) for uranium because of its high melting and boiling points. In response to the request, the US Environmental Protection Agency (US EPA) Region IV approved the use of modified RFs for elemental uranium provided no reaction had taken place to alter its chemical form. In 2015, the ORR requested approval to use different RFs for tungsten, again because of its high melting and boiling points. EPA Region IV approved the use of modified RFs for heated radioactive tungsten metal. In accordance with the two precedents set for heating uranium and radioactive tungsten metals, in 2016, the ORR requested approval to use modified RFs in a similar fashion for other radioactive solid metals and compounds with melting and boiling points above 500 °C that might be heated above 100 °C in future research projects and experiments. EPA Region IV again granted approval to use modified RFs for the list of compounds. This note discusses the proposed modified RFs and their development.
Related Concept Videos
Nuclear Power
Nuclear Fuels
Nuclear fuel consists of a fissile isotope, such as uranium-235, which must be present in sufficient quantity to provide a...
Nuclear Fission
Heating and Cooling Curves
For instance, the addition of heat raises the temperature of a solid; the amount of heat absorbed depends on the heat capacity of the solid (q = mcsolidΔT). According to thermochemistry, the relation between the amount of heat absorbed or released by a substance, q, and its...
Radical Halogenation: Thermodynamics
Radiation Pressure: Problem Solving
The average value of the rate of momentum transfer divided by the absorbing area represents the average force...
Radiation: Applications
The average...

