Line side signalling
Following several deviations and a request from Network Rail, we embarked on a full review and update of the requirements for lineside signalling equipment. Working closely with Network Rail and our own signalling, human factors and operating specialists, we looked at how the signalling system is used by train drivers and what needs to be maintained at the IM-RU interfaces. Having identified the three primary interface requirements – to ‘be readable’, ‘be interpretable’ and ’be driveable’ – we set about identifying the technical parameters and assessments that need to be specified. This work led to five new standards, setting out requirements and guidance covering:
- Signalling product parameters and performance assessment
- The signal sighting assessment process
- The appearance and meaning of lineside signalling displays
- Lineside signalling system layouts and signal aspect sequences
- A new method of evaluating whether the proposed signalling system is fit for purpose.
Duty holders can use these standards to confirm that any potential hazards are controlled as part of meeting their legal obligations to control risk as set out in the Railways and Other Guided Transport Systems (Safety) Regulations 2006 (ROGS) and the Common Safety Method for Risk Evaluation and Assessment (CSMRA).
By focusing on the overall intended benefits, the new evaluation method means that the infrastructure manager and operator can assess their plans against their performance objectives as well as their safety ones.
In collaboration with Network Rail and the Rail Delivery Group (RDG) we have so far delivered ten ‘driveability’ workshops aimed at Network Rail routes and TOCs and FOCs. These highlight the new requirements and how they will help them to identify obstacles and realise their business requirements. We are also planning a workshop for the Digital Railway programme.
Feedback from the workshops is informing our work on related standards as well as Network Rail’s own work to update and align their project management systems. A summary of the feedback will be provided to the Train Accident Review Group (TARG), a cross-industry subgroup of the Systems Safety Review Group (SSRG), highlighting any obstacles to putting the new requirements and evaluation process into practice. This way, senior managers in industry will have the information they need to resolve identified issues – such as the need for more collaboration at the project commissioning stage.
Together, the new standards and our work with Network Rail and RDG are raising cross-industry awareness and understanding of 'driveability' as well as safe integration of change affecting lineside signalling systems. By influencing signalling layout design and assessment, the new standards will help industry to realise the benefits of these projects and save the time, money (and energy) associated with rework. As billions of pounds are expected to be invested in signalling system projects over CP6, we are expecting the financial saving across industry to be millions of pounds.