A peculiarity of the VVER-440/213 design is the extremely large number (over one hundred thousand) of safety-classified SSCs because of the design features and methodology of safety classification.

After screening out the active and short-lived systems from the total safety-classified SSCs, approximately 38 000 mechanical, 6500 electrical and 2000 structural SCs have been identified to be in scope at the plant in Paks, Hungary.

Ageing management of mechanical commodities might be ensured approximately by nine vessel specific, nine pump-specific, 14 valve-specific, 22 heat-exchanger-specific, 15 piping specific, nine filter-specific programmes. There are also 15 special components requiring individual AMP. The num­ber of structural commodities exceeds 25. The AMPs and their hierarchical structure is plant specific, demonstrating that Paks NNP practise an adapta­tion of best international practice to VVER-440/213 instead of a copy-paste approach. At the same time, the Paks NPP is utilizing the ageing experi­ence of other plants and elements of an adequate ageing management pro­gramme are in line with international practice.

The specific approach practicable in the case of the VVER-440/213 plants can be shown in the example of ageing management of civil structures. The VVER-440/213 design differs very much from the usual architecture of PWRs. In the example of the Paks NPP, practically all buildings, earth structures, etc., at the plant are within the scope. Most of these building structures are complex, and heterogeneous from the point of view of struc­tural design, layout, manufacturing and construction of members, material composition and contact with environment (Katona et al, 2009a).

In the case of the Paks NPP, it would be difficult to adopt the AMPs described in the GALL Report (US NRC, 2010), where nine groups of building structures and seven groups of structural components are defined, and ten ageing management programmes cover the whole scope. At the Paks NPP the large number and variety of building structures and struc­tural components requires establishment of a hierarchical structure of age­ing management programmes.

Type A programmes have been developed for foundations, reactor sup­port structures, building movement, reinforced concrete structural members, high temperature concrete, equipment foundations, steel and reinforced con­crete water structures, liners (Carbon-steel), prefabricated panels, masonry walls, earth structures, doors and hatches, steel-structures, cable and pipe supports, paintings and coatings, SS-liners, cable and pipe penetrations, fire protection structures, main building settlement, support structures of cabi­nets, seals and isolation and corrosion in a boric acid environment. These programmes are related to specific structures, that is structural commodities or specific ageing mechanisms (e. g. building settlement due to soft soil con­ditions). An exceptional A-type programme is the control of leak tightness of the containment, which is related to the containment only.

The buildings having identified safety functions are composed from struc­tural commodities. Using these type A programmes for specific structures (commodities), 30 type B programmes have been developed which cover all plant building structures. These AMPs contain the identification of ageing effects and mechanisms to be managed, the lists and details of the proper application of type A AMPs to be applied, while managing the ageing of the given building. The type B AMP also contains logistical type information since the accessibility of certain buildings is limited.