NR NR/L2/SIG/30009/E710 ISSUE 1 PDF

This module:

a) defines the safety requirements for the provision of flank protection;

b) provides guidance on a risk-based approach to the application of flank protection.

Excluding ETCS without lineside signals, it applies to all signalling schemes and detailed design whenever:

a) the usage of lines is altered; or

b) alterations are made to the layout.

Wherever reasonable, other opportunities to review and optimise flank protection should also be taken. Such opportunities to update flank protection are likely when any of the following apply:

a) layouts are re-signalled or relocked;

b) additional routes are provided;

c) an overrun or timetable risk assessment (or similar) identifies the need to review protection.

This module does not apply to:

a) minor signalling alterations; or

b) alterations that are only a limited part of a wider junction layout.

This module provides alternative options for the provision of flank protection:

a) non-conditional flank protection;

b) conditional flank protection (various levels).

Purpose

This module:

a) controls the risk of collision between a train on a set route and an overrunning train;

b) formalises the use of conditional and non-conditional flank protection to harness the operational benefit afforded by split point controls coupled with the non-detection of facing points in the overlap;

c) more completely defines how much flank protection should be provided.

This module forms part of the Signalling Principles Handbook (NR/L2/SIG/30009) and is to be read in conjunction with the other modules of the handbook.

NOTE : This approach is consistent with the Common Safety Method for Risk Assessment [CSM] regulations and meets Network Rail’s signalling policy. It also supports Network Rail’s ‘Safe by Design’ commitment that requires the taking of reasonable opportunities to make safety improvement.