The Pool Test Reactor (PTR) was a 10 kWt reactor moderated by light water of the tank type fed with highly enriched uranium built in the Chalk River in 1957. It used uranium plate type fuel enriched to 93% - aluminum. The reactor was used to measure the ignition of fissile samples of the NRX. The reactor was designed and built by Canadair, which is now a division of Bombardier. History
On November 29, 1957 the reactor reached its criticality for the first time at 12:05 pm and quickly took over the function of ZEEP to measure the effects of reactivity of the materials, especially after irradiation. It was turned off and the fuel was removed in 1990.
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