Transient Reactor Experiment and Test Facility (TREAT)

Idaho National Laboratory, Idaho

Idaho National Laboratory
Transient Reactor Experiment and Test Facility (TREAT)
Secondary Type
No Secondary Type Defined
Tertiary Type
No Tertiary Type Defined
Core Functions
The Transient Reactor Test Facility (TREAT) provides transient testing of nuclear fuels and materials. The facility is used to study fuel melting behavior, interactions between fuel and coolant, and the potential for propagation of failure to adjacent fuel pins under conditions ranging from mild upsets to severe accidents. TREAT is an air-cooled, thermal-spectrum test facility specifically designed to evaluate the response of reactor fuels and structural materials to accident conditions. The reactor was originally constructed to test fast-reactor fuels, but its flexible design has also enabled its use for testing of light-water-reactor fuels as well as other exotic special-purpose fuels, such as space reactors. TREAT has an open-core design that allows for ease of experiment instrumentation and real-time imaging of fuel motion during irradiation, which also makes TREAT an ideal platform for understanding the irradiation response of materials and fuels on a fundamental level. TREAT was placed on standby in 1994. Operations were resumed in 2018. TREAT will provides a valuable capability to support efforts to develop accident-tolerant fuels for light-water reactors as well as the advanced reactor fuels, both of which will allow nuclear power to remain the primary source of emission-free baseload energy in the future.
Unique Functions
36" full assemblies. High-intensity (20 GW), short-duration (80 ms) neutron pulses for severe accident testing. Shaped transients at intermediate powers and times (flexible power shapes with up to 60 seconds duration). 120 kW steady state operation. Testing capability for static capsules, sodium loops, and water loops. Neutron radiography facility.
Hotwork Facilities
Support Equipment
Radiological Limit
>1R/hr @ 30cm
Materials Allowed
beta/gamma only
Sample Encapsulation
Commissioning Date
Recent Upgrade
RAM License
Department of Energy
License End Date
Docket Number
User Facility
GAIN Partner
NSUF Partner
NE Use Percentage
No NE Use Percentage Defined
Utilization Hours
No Utilization Hours Defined
Number Of Users
No Number Of Users Defined
Number Of Staff
No Number Of Staff Defined
Point Of Contact
Teri Ehresman
Website URL
Date Of Data
July 1, 2015