National standards bodies NSBs

Each country in ISO and in CEN is represented by its national standards body (NSB), which is usually the organization responsible for setting standards in its country. NSBs play an important role in the implementation of the Eurocodes.

Each country's standards body is responsible for publishing European standards as national standards with the same legal standing. NSBs may translate European standards from the official CEN text (which is produced in English, French, and German), but they must not deviate from or alter any part of that text.

The NSB must retain the prefix EN in the national designation for the relevant European Standard. For example, EN 1990 becomes: BS EN 1990 in the UK NF EN 1990 in France DIN EN 1990 in Germany

The EN designation signifies that the standard's technical content is exactly the same in all countries throughout Europe.

Each country may add a National Title Page, a National Foreword, and a National Annex to each Eurocode part.1 The National Annex provides the missing information in the Eurocode 'jigsaw', as illustrated in Figure 1.7 and discussed below.

Figure 1.7. Information provided in the National Annex to an EN Eurocode

fNational Annexes are only required for 57 of the 58 EN parts. The exception is EN 1998-3 for assessment and retrofitting of buildings.

Nationally Determined Parameters

Nationally Determined Parameters (NDPs) are parameters that are 'left open in the Eurocode for national choice'.17 NDPs include partial factors, correlation factors, combination factors, model factors, and such like.

Country-specific data

Country-specific data refers to information of a geographical nature that only has relevance in a specific country — for example, charts showing wind pressure.

The procedure to be used where a choice is allowed

Some Eurocodes allow a choice of procedures where no single procedure could be agreed by the drafting committee. Eurocode 6 allows a choice between six classes of execution control and Eurocode 7 a choice between three different Design Approaches for the STR and GEO limit states (see Chapter 6).

Guidance on the informative annexes

A country's National Annex may offer guidance on the status of any informative annexes in the relevant Eurocode. Informative annexes may be 'promoted' to normative (i.e. mandatory) status, remain as purely informative, or be dismissed as unsuited for use in that country.

Reference to non-contradictory, complementary information A National Annex can provide references to what is termed 'non-contradictory, complementary information' (NCCI), that is other design guidance that supports the relevant Eurocode without contradicting it. Where contradictions occur, Eurocode provisions take precedence.

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