Requirements for protection of Nuclear Power Plants against postulated ruptures of High-Energy Piping systems present practically in all National and International Guidelines for NPP Safety Design.

Basically this problem consists of three general parts:

1) location of postulated ruptures;

2) consideration of the pipe rupture’s consequences;

3) realization of the protective measures.

Presented paper describes the evolution and contemporary state of the problem regarding existing WWER NPPs in East Europe and Russia, as well as implementation of the High Energy Line Breaks (HELB) Analysis for the new-designed WWER Units.

Paper presents the analysis of the current Russian National Guides regarding High Energy Line Breaks (HELB) problem. On the basis of this analysis the proposals for entering in Russian National Guide documentation changes and additions are developed.

A special emphasis is given on the formulation of the intermediate rupture’s locations based on the Strength Analysis according to PNAE G-7-002-86 (Russian Code) stress equations. The numerical comparative PNAE-ASME Analysis has been performed to illustrate the main approaches of the proposed methodology.