scope:

This document summaries all SSI related hardware problems discovered following incidents and failures investigated by WS Atkins Rail, Field Support and Investigation Services (formally Opal Engineering). This will also include problems which relate to both hardware and software elements.

This document incorporates brief details of identified problems and provides the following for each situation:

• When the identified problem arose

• What the problem was/is

• What actions were taken to overcome the problem in terms of modifications/or specification changes

• Relevant references

Where further or more detailed information is required, reference should be made to TI Reports and other identified reference material.

Note: For the purposes of this document, all failures have been reduced to their root cause and categorised as such. The root cause often has little to do with the technical investigation report title, as this is invariably based on the location and end effect of the problem in question.

Guidance on whether any solutions should be applied retrospectively is outside the scope of this document.

Purpose

This Code of Practice has been prepared to summarise significant SSI hardware problems that have been previously identified within Technical Investigation Reports.