Client safety assurance of high integrity software-based systems for railway applications
Platform height, platform offset, and platform width
AC electrification and its interface with rolling stock
Lettered Differential Permissible Speeds classification
Trespass risk assessment
A key achievement for CCS SC in September 2022 was the publication of RIS-0745-CCS issue one Client safety assurance of high integrity software-based systems for railway applications. The standard is necessary because of the growing demand for software-based systems in the operational railway, many of which have failure modes that could contribute to hazards or impact on service provision. The Rail Accident Investigation Branch (RAIB) report on the Cambrian Coast Line incident which happened in October 2017 identified the need for the rail industry to 'develop and implement a mandatory safety assurance procedure (and associated guidance) for its client role on projects involving installation and modification of high integrity software-based systems’.
The new standard identifies the activities for client organisations to undertake as part of the safety management of the development, installation, and maintenance of high integrity software-based systems. It covers high integrity software-based systems where the safety functionality of the system is primarily delivered through the execution of software.
The content is applicable to all systems used in railway applications, primarily infrastructure, trains, and their operation to deliver a service.
RIS-0745-CCS issue one is intended for use by organisations when procuring and utilising high integrity software-based systems for railway applications throughout their lifecycle. It is also relevant if organisational ownership changes during the lifecycle. The standard is expected to provide industry a total value of £8.2m over a five-year period.
RIS-0745-CCS issue one
GIRT7020 issue two GB Requirements for Platform Height, Platform Offset and Platform Width was published in June 2022. The standard was revised to incorporate feedback and RSSB research project T1118 Optimising the design and position of platform markings designed to keep people away from the platform edge.
Several deviation requests have been submitted to RSSB (for GIRT7020 issue one) and to Network Rail (for the complementary RSSB standard RIS-7016-INS issue one Interface between Station Platforms, Track, Trains and Buffer Stops).
These were reviewed and considered, as well as recommendation one from RAIB report 01/2021 ‘Person struck by a train at Eden Park station’ which requires the industry to work together for a clear policy and process for provision of tactile surfaces.
RIS-7700-INS issue three Rail Industry Standard for Station Infrastructure has also been reviewed and partially withdrawn to transfer some platform-related clauses to RIS-7016-INS where they are now incorporated for consistency.
The revised GIRT7020 has updated requirements and guidance in platform cross-fall requirements, platform edge markings, platform widths, possible warning signs for platform cross-fall or gradient, and incorporation of the clarification on clearances.
References to TSIs were also updated to reference NTSNs GIRT7020 and RIS-7016-INS are intended for those responsible for designing, installing, managing, modifying, or maintaining station platforms or track adjacent to platforms, and those responsible for buffer stops.
GIRT7020 issue two
GB Requirements for Platform Height, Platform Offset and Platform Width
RIS-7016-INS issue two
Interface between Station Platforms, Track, Trains and Buffer Stops
This collection of standards plays an important role in supporting new, renewed, and upgraded AC electrification infrastructure and its interface with rolling stock. The multi-functional nature of this project has involved a high degree of collaboration to establish consensus and thereby achieve an appropriate and successful outcome.
This revision builds upon the more limited changes undertaken in 2019. It is the first substantial change to this suite of standards since they were published nearly ten years ago and takes place in the new post-EU exit era.
The overhead AC electrification system and the rolling stock using it must be compatible, and the interface between these two subsystems is critical to the safe and successful delivery of passenger and freight services. The main technical requirements are set out principally in the NTSNs for the Energy and Rolling Stock subsystems. The NTSNs permit options and different arrangements in certain circumstances, and these are contained in NTRs, in the form of two revised Railway Group Standards (RGSs). These standards are complemented by two Rail Industry Standards (RISs) which contain those requirements considered by industry to add-value, but to not meet the narrow criteria to be an NTR.
This project has removed any overlap between documents, removed requirements which can be more effectively addressed by alternative means such as within company or project-specific standards and documents, and has led to the withdrawal of two guidance notes from the catalogue. These RSSB documents now present their content in an easier way to assist users’ understanding of the purpose of each requirement. This root and branch revision has resulted in a substantial rationalisation and simplification of requirements within these RSSB documents, such that overall content has reduced by approximately 50%, without any loss of quality.
These updated documents are projected to deliver industry benefits in excess of £27m over a five-year period per 100 single track kilometres of electrification, principally through cost reduction in the design, construction and maintenance of AC electrification infrastructure. Given the scale of these benefits, the programme was also accelerated to enable the industry to take advantage of these changes at the earliest opportunity. This resulted in publication in December 2022, six months ahead of the committed schedule.
GMRT2111 issue three
Rolling Stock Subsystem and Interfaces to AC Energy Subsystem
GLRT1210 issue three
AC Energy Subsystem and Interfaces to Rolling Stock Subsystem
RIS-2715-RST issue one
RIS-1853-ENE issue one
Lettered Differential Permissible Speeds (LDPS) are used to permit certain types of rolling stock with the necessary characteristics to operate at increased speeds on particular sections of the network, without the cost and disruption of modifying the infrastructure to raise the line speed for all rolling stock.
There are different categories of LDPS which are indicated on the network by different combinations of letters. They are set out in RIS-2711-RST Lettered Differential Permissible Speeds Classification and RIS-7706-INS Process for Adding, Removing or Modifying Lettered Differential Permissible Speeds. These standards address infrastructure and rolling stock characteristics for the use of LDPS indicated by the letters ‘SP’ (Sprinter), ‘MU’ (Multiple Unit), and ‘HST’ (High Speed Train).
RIS-2711-RST and RIS-7706-INS take the output from an RSSB research project, T1163 ‘Criteria for assigning differential speed categories’. This developed clear criteria for the categorisation of rolling stock as HST or MU. The project also identified that there is no longer any need to differentiate between MU, EMU, and DMU. This is because a single category ‘MU’ meets the same need.
These new and updated standards enable existing and new vehicles to be deployed to best effect to optimise journey times, route capacity and asset utilisation. By applying RIS-2711-RST, new rolling stock can be designed with a clear understanding of which categories it will, and will not, satisfy. RIS-7706-INS determines the infrastructure characteristics necessary to support the trains designed in accordance with RIS-2711-RST.
The application of these standards will contribute an estimated minimum industry net benefit of £12.5m over a ten-year period. This will simplify the process of categorising infrastructure and rolling stock by the publication of clear and agreed criteria.
RIS-2711-RST issue two
Lettered Differential Permissible Speeds Classification
RIS-7706-INS issue one
Process for Adding, Removing or Modifying Lettered Differential Permissible Speeds
A key output for the Traffic Operations and Management Standards Committee this year was the publication of a new standard, RIS‑3786‑TOM Trespass Risk Assessment, that provides a framework for conducting trespass risk assessments.
The standard was created in response to the continued industry need to effectively mitigate trespass risk. This is currently at a very high level on the GB mainline and does not show clear signs of decreasing. Incidents of trespass have a significant impact on the network, the public, and the whole rail industry. They carry the risk of injury and harm for those trespassing, along with significant delay to the travelling public. They also carry a risk of prosecution and fines for transport operators, with the overall costs to industry of trespass incidents estimated to be around £100m annually.
Previously, methods of assessing and managing trespass risk were disparate and inconsistent across the industry. There was an opportunity to simplify and streamline the risk assessment process so that good practice can be applied consistently across all locations. RSSB research project T1183 Good practice guide to assessing trespass risk developed a system for trespass risk assessment with a suggested framework and methodology with clear and universally applicable parameters.
Following publication of the outputs of this research, the Trespass Risk Group requested that the findings from T1183 be put into a Rail Industry Standard. Accordingly, with considerable input and engagement with key industry groups and stakeholders, the new standard was created.
RIS-3786-TOM is designed to help anyone involved in assessing trespass risk to understand and analyse the risk and risk levels, then select and implement appropriate measures to mitigate the risk of trespass.
The introduction and adoption of a common approach to addressing trespass risk is expected to deliver an overall reduction in incidents, which will, in turn, reduce the
associated harm. Resultant delays (and costs) will reduce, and passenger satisfaction and public safety will improve. It is anticipated that the standard will deliver benefits of £2.97m over five years.
RIS-3786-TOM issue one
Trespass Risk Assessment
