The reactor was built in cooperation with the Atoms for Peace program run by the US Dept Of Energy in the 1950s and '60s.

In March 1965 the reactor was commissioned and initially operated at 6.75 MW, a limitation imposed by the capacity of the secondary cooling circuit.

Output was increased to 20 MW in 1968 after the secondary cooling circuit was upgraded.

[5] Initially the reactor was fueled with High Enriched uranium (HEU) supplied by the United States, but in 1975 exports of HEU from the USA to South Africa was suspended in protest of South Africa's nuclear weapons program and the construction of the Valindaba Y-plant.

[9][10] Radio isotopes are distributed through NTP Radioisotopes, a subsidiary company of NECSA