N290.2-11

1 Scope 1.1 This Standard covers the design, qualification, installation, operation, maintenance, inspection, and documentation of the emergency core cooling (ECC) system for a water-cooled nuclear power plant. 1.2 The ECC system’s primary purpose is to transfer heat from the reactor core following a loss of reactor coolant that exceeds the makeup capability of process systems. This Standard also applies to all support systems required to ensure that the ECC system is able to maintain adequate heat transfer for as long as necessary to maintain the release of radioactive material within reference dose limits by limiting fuel failure. 1.3 This Standard was written as a companion document to CSA N290.0, which outlines general requirements for safety systems. 1.4 This Standard uses the term “ECC system” to refer to either a single system or multiple systems depending on the plant design. 1.5 In CSA standards, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (nonmandatory) to define their application.