CNSC Design Requirements for Small Reactor Facilities (Focus on Differences from those for NPPs)

The Canadian Nuclear Safety Commission (CNSC) has established the regulatory framework for the efficient and effective licensing of all nuclear reactor facilities. This regulatory framework includes the documentation of the requirements for the design and safety analysis of all nuclear reactor facilities whether they are small reactor facilities or nuclear power plants (NPPs) regardless of size. For this purpose, the CNSC has published the design and safety analysis requirements in the following two sets of regulatory documents: 1. RD-367, Design of Small Reactor Facilities and RD-308, Deterministic Safety Analysis for Small Reactor Facilities; and 2. RD-337, Design of New Nuclear Power Plants and RD-310, Safety Analysis for Nuclear Power Plants. These regulatory documents have been modernized to document past practices and experience, and to be consistent with national and international standards. These regulatory documents provide the requirements for the design and safety analysis at a high level presented in a hierarchical structure. These documents were developed in a technology neutral approach so that they can be applicable for a wide variety of water cooled reactor facilities. This paper focuses on the key differences in the design requirements as applied to small reactor facilities in comparison with those applied to NPPs, in particular: 1) The application of a graded approach to make the documents applicable for a wide variety of designs, power levels and utilization associated with small reactor facilities; and 2) Utilization aspects associated with small reactor facilities. Finally, this paper presents some of the proposed considerations in design requirements to implement specific details of the recommendations of the CNSC Fukushima Task Force Report. Major changes were found unnecessary since the original version of these documents already contained requirements to address most of the lessons learned from the Fukushima event of March 2011