US and Canadian regulators complete joint review of Terrestrial’s IMSR

Wednesday, 8 June 2022

The Canadian Nuclear Safety Commission (CNSC) and the US Nuclear Regulatory Commission (NRC) have had agreements since 2017 to cooperate in reviewing advanced reactor and small modular reactor (SMR) technologies.

As part of a Memorandum of Cooperation between the CNSC and NRC from 2019 they carried out the joint review of Terrestrial Energy’s Postulated Initiating Events analysis and methodology for the IMSR, which Terrestrial said was "foundational for further regulatory safety reviews" and supports its "regulatory programme to prepare licence applications required to operate IMSR plants in Canada and the USA".

Simon Irish, CEO of Terrestrial Energy, said: "This review by the Canadian and US regulators is a joint examination of the fundamentals of IMSR safety and is a cornerstone technical nuclear safety review that builds further confidence in IMSR technology and supports our national regulatory programmes. Completing this joint review is an important step forward in the commercialisation of the IMSR and paves the way for further cross-border collaboration."

Former President of the CNSC, Michael Binder, said the joint review provided "clear evidence that international regulatory harmonisation is possible. Reviews by independent national regulators provide confidence and credibility to the technologies involved as well as build momentum for global roll out".

And Jeff Merrifield, a former NRC commissioner, said the joint review "represents a milestone in efforts of the CNSC and NRC to reduce regulatory duplication and is an important step in harmonising the regulatory reviews of the two regulators".

Terrestrial Energy’s IMSR is a 4th generation reactor that uses molten salt as both fuel and coolant, with integrated components, that can supply heat directly to industrial facilities or use it to generate electrical power. It aims to commission the first power plants based on the small modular reactor within a decade. Its IMSR400 configuration, with twin reactors and generators, will mean an overall power plant design with a potential output of up to 390 MWe.