14.7 - Fault and Protection Schedule - EDF Hinkley Point

PRE-CONSTRUCTION SAFETY REPORT
CHAPTER 14: DESIGN BASIS ANALYSIS
SUB-CHAPTER : 14.7
PAGE : 47 / 48
Document ID.No.
UKEPR-0002-149 Issue 02
Action Defence line System
RCP [RCS] depressurisation
First line Normal and auxiliary spray
Second line Pressuriser safety valves
RCP [RCS] boration to ensure core First line Chemical and volume control system
sub criticality
Second line Extra boration system
RCP [RCS] cooldown
First line Main steam bypass
Second line Main steam relief trains
First line Residual heat removal system
Long term residual heat removal
Containment heat removal system
Second line
and direct safety injection
Due to the absence of detailed EOPs, no additional detailed actions are presented (e.g.
accumulator isolation, heaters cut-off, etc). The present analysis assumes that these actions are
safely carried out. The containment of radioactive material is performed and ensured
automatically, when necessary, while reaching the controlled state.
The procedures use the available systems to perform these actions and the diverse means to
reach the safe shutdown state is presented at the system level. Sub-chapter 3.2 provides
information on the classification of the systems credited in the current analysis.
Note: Class 1 manual actions with F1A architecture requirements are not required for the safe
state. If they are provided to reach the safe state, it is due to their implementation in order to
reach the controlled state in the following PCCs: Steam Line Break, Feedwater Line Break, and
pipework failure on a main cooling train (states A to F).