TRIGA

TRIGA (Training, Research, Isotopes, General Atomics) is a class of small nuclear reactor designed and manufactured by General Atomics. The design team for TRIGA, which included Edward Teller, was led by the physicist Freeman Dyson.

TRIGA is a pool-type reactor that can be installed without a containment building, and is designed for use by scientific institutions and universities for purposes such as undergraduate and graduate education, private commercial research, non-destructive testing and isotope production.

The TRIGA reactor uses uranium zirconium hydride (UZrH) fuel, which has a large, prompt negative fuel temperature coefficient of reactivity, meaning that as the temperature of the core increases, the reactivity rapidly decreases. It is thus highly unlikely, though not impossible for a nuclear meltdown to occur. Because of this unique feature, it can be safely pulsed at a power of 22,000 megawatts, even though it is a low power reactor. TRIGA was originally designed to be fueled with highly enriched uranium, but in 1978 the US Department of Energy launched its Reduced Enrichment for Research Test Reactors program, which promoted reactor conversion to low-enriched uranium fuel.

The TRIGA was developed to be a reactor that, in the words of Frederic de Hoffmann, head of General Atomics, was designed to be "safe even in the hands of a young student."Edward Teller headed a group of young nuclear physicists in San Diego in the summer of 1956 to design a reactor which could not, by its design, suffer from a meltdown. The design was largely the suggestion of Freeman Dyson. The prototype for the TRIGA nuclear reactor (TRIGA Mark I) was commissioned on 3 May 1958 in San Diego and operated until shut down in 1997. It has been designated as a nuclear historic landmark by the American Nuclear Society.

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