The American Nuclear Society has designated the High Flux Isotope Reactor a Nuclear Historic Landmark.

Located at the Department of Energy’s Oak Ridge National Laboratory, HFIR has been providing neutrons for research and isotope production for 48 years.

The reactor was conceived in the late 1950s as a production reactor to meet anticipated demand for transuranic isotopes. Today the 85 MW reactor, which is on its 455th fuel cycle, is one of the world’s sole sources of the radioisotope californium-252, used in industry and medicine.

HFIR has also been a key contributor to four decades of research into materials for use in all types of nuclear reactors; from basic materials research to the development of advanced alloys for fusion or space reactor applications.

A major upgrade to HFIR in 2007 provided improved beam lines, new instruments and a cold source that expanded its research capabilities by literally chilling, or removing energy from, the neutrons.

The reactor is expected to remain one of the world’s most capable reactor-based neutron science, radioisotope production and materials irradiation facilities for many years.

"The ANS Nuclear Historic Landmark signifies that a nuclear facility has played an important role in nuclear science and engineering," said ANS president Michaele C. Brady Raap. "HFIR, with its preeminent role in isotope production and neutron science, certainly meets that criteria."

HFIR joins the Graphite Reactor, Tower Shielding Reactor, Oak Ridge Electron Linear Accelerator, the Molten Salt Reactor and the Radiochemical Processing Plant as ANS Nuclear Historic Landmarks at ORNL.

The High Flux Isotope Reactor vessel at Oak Ridge National Laboratory