Updates to National Technical Specification Notices for rail interoperability
Source: gov.uk (2025-03-05)

Following a comprehensive review, the government will publish updates to 7 NTSNs.

The government will shortly publish updates to 7 National Technical Specification Notices (NTSNs) for Great Britain’s (GB) railway. This follows a comprehensive review aimed at improving standards for the safety, reliability, technical compatibility, accessibility and environmental protection of our railway.

NTSNs set mandatory technical requirements and procedures for the design, build, operation and maintenance of rail vehicles, infrastructure and components. NTSNs apply to both passenger rail and freight on both the conventional mainline and high-speed rail networks (HS1 and HS2) as well as the UK section of the Channel Tunnel.

NTSNs replaced EU regulations called Technical Specifications for Interoperability (TSIs). Britain’s railways were built with significant technical differences from those of continental Europe, meaning that full alignment with TSIs was never possible. In several cases, while an EU member state, we had to make use of national specific cases and exemptions from TSI requirements, both of which are permitted within the EU framework.

The European Commission updated these regulations in 2023, prompting the UK to consider the benefits of adopting similar requirements or taking a different approach. This also presented an opportunity to fix many issues within the current NTSN requirements.

Department for Transport (DfT) officials worked closely with industry through working groups and consultations facilitated by the Rail Safety and Standards Board (RSSB) to review the newly published TSIs, so that our decisions on NTSNs could be informed by those who will apply them. RSSB submitted recommendations for change in 2024, reflecting the balance of views of its industry members.

RSSB’s review found benefits in maintaining consistency with TSIs on technical requirements for the design and manufacture of rail products. This will be critical in ensuring that the rail industry continues to benefit from international supply chains and from the deployment of new rail technology being rolled out across Europe. Additionally, the review identified some areas where taking a different approach from TSIs would reduce or avoid costs, improve clarity, and deliver a safer, more interoperable and accessible railway in Great Britain.

The previous government committed to informing Parliament through a written ministerial statement if it planned to diverge substantively from TSIs, and we intend to honour this commitment. However, it is in the interest of Britain’s rail industry that we retain the ability to act quickly to correct problems, for example where requirements prove unworkable, stakeholders find errors or where safety authorities identify an urgent need for change.

I should therefore clarify that, for the purpose of that commitment, we are now defining substantive divergence as any new difference between TSIs and NTSNs that could prevent a product from complying with both sets of standards. We understand that this was Parliament’s concern when this commitment was made, and that Parliament wished to avoid placing additional costs on manufacturers operating in both the UK and EU markets by requiring separate production lines for each market.

Five NTSN specifications will meet the definition of substantive divergence from EU TSIs. Two will maintain higher accessibility requirements for train doors and seats, and one will maintain a higher safety requirement for a key train driving component. This will mean that meeting the TSIs’ specifications will not necessarily mean that the NTSNs’ higher specifications are met. The other 2 changes will set more pragmatic requirements for freight wagon brakes and electric train pantographs, meaning that products meeting the NTSNs’ specifications will not necessarily meet the requirements in the TSI.

We will also make other changes that will differ from TSIs but do not meet our definition of substantive divergence. These changes mainly concern operational requirements, processes and responsibilities for building, enhancing and maintaining the GB mainline railway, or for integrating equipment within the rail system. Differing from the TSIs in these areas will reduce or avoid regulatory burdens and costs. They also concern areas where British technical requirements already differ from TSIs due to the distinct historic legacy of Britain’s railways and take account of differences between the UK and EU regulatory frameworks, for example by referring to UK rather than EU legislation and to UK bodies rather than EU institutions. These changes have unanimous support from the GB rail industry, including manufacturers.

We are satisfied from the evidence of the industry review and consultation that differing from TSIs in these areas will not increase costs and remains consistent with the essential requirements of Britain’s rail interoperability framework.

My officials have thoroughly assessed industry’s proposals in discussion with RSSB, Network Rail and key industry bodies, and we intend to incorporate them within the updated NTSNs, with minor modifications to ensure they work in practice and are legally robust. We have also revised the introductory sections to clarify their intended purpose and scope, to ensure that these standards are applied proportionately, effectively and as intended, for example by clarifying the scope for alternative solutions where there may be better ways of achieving the same outcomes. My officials have prepared a de minimis assessment of the changes, which was cleared by the government’s Better Regulation Unit.

Our approach is fully compliant with our international obligations, which include the EU-UK Trade and Cooperation Agreement, the Convention concerning International Carriage by Rail (COTIF) and the Windsor Framework, which requires continued application of TSIs in Northern Ireland. We are also assured that this approach is consistent with formal arrangements to ensure international rail traffic through the Channel Tunnel.

Publishing these updated NTSNs is an important first step in improving Britain’s rail standards framework, but there remains much more to be done. The public consultation that informed the NTSN revisions identified further areas for NTSN changes that could improve efficiency and reduce cost, including on rail electrification. We are keen to explore these and anticipate further updates to the NTSNs over the coming months and years. We are also considering options for reforming the rail technical standards framework itself to create a system fit for the improved railway this government will deliver through Great British Railways. We will consult on these options in due course.