PTAN 2018 Dimensional Reference N1*N2 N3

The purpose of this guide is to serve as a dimensional reference standard assisting the nuclear pressure equipment Manufacturer, of category I to IV and subject to Appendix II or III of the ESPN order [2] (level N1*1, N2, or N3), in the design and manufacture of equipment, taking these requirements into consideration.

This guide describes the principles enabling the Manufacturer :

• during the design, to define the so-called “main” dimensions including the dimensions necessary for the respect of the French regulatory requirements (DNRE),
• to define the DNREs (Dimensions Necessary to Respect the Requirements) that are part of the main dimensions and that are taken from:
  • the requirements mentioned in Appendix II or III of the ESPN order [2],
  • radiation protection requirements defined by the professional guide, taking into account the requirements mentioned in Appendix IV of the ESPN order [2];
• during the manufacture, to follow a documented process of dimensional inspection and traceability of these main dimensions.

When this document uses the term “Manufacturer”, this term should be understood in the sense of Article 6 of directive 2014/68/EU[1].

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1 NPE level N1* are the pipes of the main primary circuit of nuclear water boilers DN less than or equal to 50 and other category I to III and level N1 piping with DN less or equal to 100 as well as the pressure accesories of the same DN which are connected to them (see article 5. 1.b) of the NPE order [2]).

[1] Directive 2014/68/EU of 15 May 2014, on the harmonisation of the laws of the Member States relating to the making available on the market of pressure equipment

[2] The order of 30 December 2015, as amended, relating to nuclear pressure equipment.