This document applies to all staff that perform preventative or corrective maintenance to signalling assets on Network Rail managed infrastructure.

The intervals relate to the maintenance tasks defined in the Signal Maintenance Specifications, or that need to be applied for Reliability-Centred Maintenance.

Purpose

The purpose of this document is to set the safety and performance intervals applicable for carrying out signalling maintenance tasks and tests.

The intervals shown are intended to maintain the designed safety and reliability, by detecting and correcting deficiencies to signalling equipment before there is deterioration or failure.