Preface

This is the fifth edition of CSA N285.4, Periodic inspection of CANDU nuclear power plant components. It supersedes the previous editions, published in 2005, 1994, 1983, and 1978. It is one of the CSA N285 series of Standards on CANDU nuclear power plant components.

Scope

1.1
This Standard defines requirements for the periodic inspection of pressure-retaining systems, components, and supports that form part of a CANDU nuclear power plant.

1.2
This Standard addresses
(a) failure aspects;
(b) classification of areas subject to inspection;
(c) provision for access;
(d) inspection techniques and procedures;
(e) personnel qualifications;
(f) frequency of inspection;
(g) responsibilities;
(h) documentation;
(i) records;
(j) evaluation of inspection results;
(k) dispositioning; and
(l) repair requirements.

1.3
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; "may" is used to express an option or that which is permissible within the limits of the standard; and "can" is used to express possibility or capability. 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 (non-mandatory) to define their application.