Argonne National Laboratory
Reduced Enrichment for Research and Test Reactors
Nuclear Science and Engineering Division at Argonne
U.S. Department of Energy


RERTR FUEL TESTS  As part of the advanced fuel development program for RERTR, fuel samples are being tested in Department of Energy's Advanced Test Reactor at Idaho National Laboratory.

The Reduced Enrichment for Research and Test Reactors (RERTR) Program develops technology necessary to enable the conversion of civilian facilities using high enriched uranium (HEU) to low enriched uranium (LEU) fuels and targets. The RERTR Program was initiated by the U.S. Department of Energy in 1978. During the Program's existence, more than 70 research reactors have been converted from HEU (= or >20% U-235) to LEU (< 20% U-235) fuels, nearly 30 additional reactors that used HEU have been verified as shutdown, and processes have been developed for producing radioisotopes with LEU targets. The RERTR Program is managed by the Office of Material Management and Minimization in the National Nuclear Security Administration (NNSA). The main technology components of the program are:

  1. the development of advanced LEU fuels,
  2. design and safety analysis for research reactor conversion, and
  3. development of targets and processes for the production of the medical isotope Molybdenum-99 with LEU.

Fuels for Research and Test Reactors

Design and Safety Analyses for Research and Test Reactors

Radioisotope Production

Reference Documents concerning the RERTR Program

RERTR International Meetings

2023 RERTR Meeting

RERTR-2022 International Meeting

The United States Department of Energy / National Nuclear Security Administration's Office of Material Management and Minimization (M3) will host the RERTR-2023 International Meeting on Reduced Enrichment for Research and Test Reactors in Denver, Colorado, USA on November 5-8, 2023.

Past RERTR International Meetings



RERTR Meeting Archive (1995-2004)

For the complete list of RERTR International Meetings, see RERTR International Meetings


See list of RERTR Program contacts


Mission Statement

The RERTR program mission supports the minimization and, to the extent possible, elimination of the use of HEU in civil nuclear applications by working to convert research reactors and radioisotope production processes to the use of LEU fuel and targets throughout the world.

2023 RERTR Meeting

The 2023 RERTR International Meeting (RERTR-2023) will be held November 5-8, 2023 in Denver, Colorado, USA.
For more information visit RERTR-2023.


Useful Links


ARGONNE NATIONAL LABORATORY, Nuclear Engineering Division, RERTR Department
9700 South Cass Ave., Argonne, IL 60439-4814
A U.S. Department of Energy laboratory managed by UChicago Argonne, LLC

Last modified on May 18, 2020