+44 (1732) 833111
+1 (732) 333 8853Signal Overrun Risk Assessment Tool (SORAT)
As part of Network Rail’s on-going safety and performance improvement commitments and in compliance with the requirements of RSSB’s Railway Industry Standard Reference RIS-0386-CCS, Network Rail developed a bespoke web based tool to quantify, mitigate and manage risk associated with overrun risk within UK infrastructure. The resultant software package was the Signal Overrun Risk Assessment Tool (SORAT).
Project Scope
The key driver for this project was assessing and reducing the risk and consequential impact of a train to train collision following a SPAD. The core functionality of the system can be split into 3 areas and this is carried out for both existing railway and for all infrastructure change projects:
Quantitative Risk Assessment
- A risk engine consisting of mathematical algorithms that quantify the overrun risk on a signal by signal basis.
- Desktop exercise using known parameters that are fed into the software and used in the calculations.
- Output is a number of risk scores in units FWI/yr which can be used as a filtering exercise to take the higher risk signals to a qualitative review.
Qualitative Risk Assessment
- The higher scoring signals and those with other concern (SPAD History) are taken through an expert judgement workshop to discuss the risk in more detail.
- The SPAD Probability is varied for local conditions and distractions using 16 questions within the VariSPAD protocol developed by RSSB.
- Multiple mitigation measures can be suggested and their benefits assessed through the Cost Benefit Analysis module
Management and Audit
- Full audit trail of decision making and process. Each and every change in the system is logged and is searchable by the administrator.
- Inbuilt commissioning process for handover from new schemes to the existing railway
- Inbuilt checking and acceptance processes
- All algorithm parameters are available to the administrator and the system can be calibrated without the need to update the system
- Four levels of user with allocation to project folders managed by super users and administrator within the system.
- Algorithms were validated and checked by an individual third party and the output verified by the RSSB.
- Ongoing development of the system is directed by the SORAT steering group which meet monthly and is made up of Network Rail, RSK Business Solutions and RSSB.
Methodologies Used
SORAT is a truly innovative solution, taking a novel approach to the measurement of this specific operational risk. SORAT sets the worldwide benchmark for managing overrun risk.
Our powerful risk management tool - which was written from scratch and uses a large amount of complex mathematical algorithms - helps Network Rail to improve performance and more importantly the on-going safety across the whole rail network.
To deliver the system, we worked with the Research and Development team within RSSB in order to understand the bespoke nature of the risks and mitigations.
Network Rail have nominated SORAT for the national partnership awards and updated releases of the system are already planned which will build in other risk assessment methodology such as SPAD into Level Crossing and an assessment of risk for trackside workers.
Final Deliverable
Technical Specification
SORAT is a fully web based tool which is hosted within Network Rail environment but is available to users both internal and external to Network Rail. SORAT is designed using enterprise level architecture using Java J2EE and Oracle 11g as the relational database management system. The solution has been deployed on WebSphere Application Server v7.0.
Go Live and System Support
SORAT has been live for 3 years and has been received exceptionally well by the industry. There are currently 300 risk assessors with access to the system and over 13000 risk assessments have been completed since go live.
SORAT is ready to be implemented elsewhere and may be available within 6 weeks of sign up. The solution on offer will be hosted and supported by RSK Business Solutions Ltd or we can configure the system to work within the client’s network.
The system can be calibrated to fit with any infrastructure environment with possible guidance from RSSB research.
System training is carried out by RSK Business Solutions Ltd or we can offer train the trainer guidance to get trainers up to speed with the system, the process and the algorithms. RSK Business Solutions also offer technical support on the SORAT process and manage the part 2 competence assessments for newly trained assessors.
