NR NB 173 ISSUE 1 PDF

Consideration of derailment risk is to be undertaken by projects that change the derailment risk. The following are examples of scope that could change the derailment risk:

• Introducing HPSS to the network,

• Modifying Signals or Controls protecting and/or reading over HPSS,

• Relocating Switch and Crossings controlled by HPSS.

Note – consideration of derailment risk is part of RIS-0386-CCS.

Purpose

This Notice Board sets out guidance on a process for Derailment Risk Assessment for the High Performance Switch System (HPSS) utilising the Signal Overrun Risk Assessment Tool (SORAT) and provision of TPWS to current standards.