CSA N285-0.1:2018 pdf download.Commentary on CSA N285.0-1 7, General requirements for pressure-retaining systems and components in CANDU nuclear power plants
1.1 General
The purpose of this Commentary is to provide background information for specific clauses and requirements in CSA N285.0. This background information can help the user to clarify the context of the CSA N285.0 requirements. Also, this Commentary refers to sources of material that were used during the formulation of some of the requirements in CSA N285.0. With the exception of the Annexes, the main clause headings and the main clause numbers used in this Commentary correspond to those in CSA N285.0-17. The numbering for subclauses in the Commentary does not necessarily correspond to
those in CSA N285.0-17.
This Commentary addresses requirements relating to the design and construction of pressure-retaining systems and components. Standards that relate to periodic inspection of pressure-retaining components are not addressed. Also, the requirements of other interfacing Standards and ASME BPVC, Section 1, Division 1 are not addressed in this Commentary. The discussion provided in this Commentary is directed towards the requirements in CSA N285.0-17 and does not address the amendments released since 2017. Generally, the text is presented in the same sequence used in CSA N285.0, tracing the activities during the design, fabrication, and installation of an item.
Although this Commentary can be read by itself, a better understanding of the Commentary will be obtained if a copy of CSA N285.0-17 is available for reference. Many of the requirements in CSA N285.0-17 are described in this Commentary. However, the Standard must always govern since it provides the formal requirements.
Note: ASME has published a companion guide to the ASME Boiler and Pressure Vessel and Piping Codes, which provides the criteria and a commentary on selected aspects of ASME Boiler and Pressure Vessel and Piping Codes.
1.2 Historical background
The requirements in the Standard are based on provincial and federal regulations, practices developed in the design and construction of CANDU nuclear power plants, and the proven and widely adopted rules of ASME BPVC, Section I, Division 1. Their fundamental goal is to ensure public safety. Since the first Standard in the CSA N285 series was issued, regulations and best practices have evolved as the industry gained design, construction, commissioning, and operational experience. However, the basic pressure boundary requirements have not changed significantly and are based on the long- standing ASME and industrial practices. Where such changes have occurred, they are described in the appropriate sections.CSA N285-0.1 pdf download.