scope:

This specification applies to all signalling schemes and where signals are altered or introduced or where a signaller's diagram is renewed, altered or introduced.

Purpose

This section 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.

This section details Network Rail's policy on identification of the primary signal identity where more than one control device operates a signal and of slotted signals controlled by two signal boxes. This section comprises mandatory sections, statements of good practice (which shall be followed unless an alternative can be demonstrated to be beneficial to the company and no less safe), and guidance on historical practices (which are not to be applied to new works but provide information on previous standards or their interpretation.