scope:

This standard does not include the maintenance of the Platform Automatic Train Communications system (PACS). 

The primary user of this standard shall be the Asset Steward. 

This standard supersedes E7709 A5 and TLL-ENG-S7273-A1, which are withdrawn.

Purpose 

This standard defines the minimum requirements for the maintenance of the fixed part of the track/train datalink sub system which forms part of the stand alone correct side door enable system.

The purpose of correct side door enable is to restrict the opening of train doors where it is unsafe to do so. This system is designed to high integrity standards.