scope:

This guidance and the procedure that it supports apply to all instances of Product Change whether for use on fixed LU infrastructure or on rolling stock running on LU infrastructure. This includes:

a) new products

b) changes to products currently in use, such as physical modifications and updates to software, firmware or data

c) product-related changes, such as maintenance & overhaul procedures, testing procedures, manufacturing processes, etc

d) new applications of products currently in use

e) trials or temporary deployment of products or changes

f) non-S,C&I changes of the types described above that could impact on S,C&I assets.

Purpose

The purpose of this document is to provide guidance to all those with responsibilities under procedure PR0635 'Signalling product approval'. Also, it provides guidance on when the procedure should be applied and on the execution of each step.