scope:

This specification applies to conventional fixed block wayside signalling. This specification and shall be used by all those engaged in system design, application design of fixed block wayside signalling. It shall be used when new or modified designs are being produced.

Note: This specification does not apply to continuous automatic train protection, automatic train control system, non-vital control systems and to depots.

For areas in which multiple aspect signalling is employed to facilitate the operation of other Train Operators, special consideration shall be agreed with LU.

Purpose

The purpose of this specification is to set out the London Underground (LU) functional and performance requirements for the safe system design and application design of conventional fixed block wayside signalling.