The integration of European railways necessitated a unified set of technical requirements to allow trains to cross borders seamlessly. Directive 2016/797 – railway interoperability, part of the Fourth Railway Package, establishes the framework for the technical and operational coherence of the EU railway system. It outlines the conditions that railway subsystems and components must meet to achieve interoperability within the EU railway network, aligning with other regulations such as Directive 2016/798 on railway safety. The primary goal is to ensure that rolling stock and infrastructure meet uniform essential requirements, including safety, reliability, technical compatibility, environmental protection, and accessibility, enabling harmonious railway operations across the Union. This directive replaced previous regulations, such as Directive 2008/57/EC, and introduced a new approach to vehicle certification, emphasizing the central role of the European Union Agency for Railways in the approval process.
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Conformity Assessment Procedures for Vehicles and Components
Directive 2016/797 – railway interoperability divides the railway system into structural subsystems, including rolling stock, infrastructure, energy, and control systems, both trackside and onboard. It identifies interoperability constituents, which are critical components of these subsystems, such as wheelsets, cab signaling devices, and pantographs. Each subsystem is governed by detailed Technical Specifications for Interoperability (TSI), which contain mandatory technical requirements standardized across the EU. Manufacturers or entities introducing new vehicles or infrastructure elements must demonstrate compliance with the relevant TSI through the EC verification procedure, an independent conformity assessment conducted by a notified body, certified by a member state. The notified body reviews project documentation, oversees tests, and issues an EC verification certificate confirming the subsystem’s compliance with TSI requirements. The tasks of the notified body begin at the project stage and cover the entire construction period, testing, and acceptance, culminating in the subsystem’s market introduction. To facilitate the process, intermediate statements of verification can be issued, covering specific stages or parts of the subsystem, which collectively form the final verification certificate.
For interoperability constituents, such as specific types of bogies, braking systems, or radio communication systems, manufacturers must obtain an EC certificate of conformity or suitability for use, based on an assessment by a notified body, and issue an EC declaration for the component type. Components bearing the CE marking and EC declaration can be freely used in vehicles across the EU without additional national approvals.
Once EC verification certificates are obtained for the subsystems comprising a rail vehicle, the applicant, typically the manufacturer, prepares the technical documentation and EC declaration of verification for the entire vehicle. This declaration certifies that the vehicle, as an integrated set of compliant subsystems, meets all the directive’s essential requirements. With this documentation, the entity applies for authorization to place the vehicle on the market, a concept introduced by Directive 2016/797, defined as the first availability of the vehicle on the EU market in a ready-to-operate state under normal or foreseeable degraded operating conditions. Essentially, it refers to the formal approval for vehicle operation under specified conditions.
Impact of the Directive on Standardization and Approval Processes
Under the new rules, applications for vehicle authorization are now submitted to the EU Agency for Railways (ERA) through a single-window system. Manufacturers must specify the intended area of use (rail networks in specific countries) and provide the necessary compliance evidence. ERA plays a leading role in the assessment, verifying submitted documents, particularly checking that all vehicle subsystems have valid EC declarations and certificates of compliance with the relevant TSI. Simultaneously, the Agency collaborates with national authorities, such as national safety authorities, to confirm the vehicle’s compliance with the network in a given country and any additional national regulations, known as open points not covered by TSI. Directive 2016/797 allows national authorities, like the President of the Office of Rail Transport in Poland, to issue temporary operation permits while verifying network compliance in cooperation with the infrastructure manager, which should occur within three months of notification. The final authorization to place the vehicle on the market, or operation approval, is issued by ERA. For this purpose, ERA evaluates subsystem documents and their TSI compliance, while also seeking national authority confirmation of the vehicle’s compliance with infrastructure and national regulations. The ERA’s authorization procedure remains largely consistent regardless of the number of countries, with the Agency issuing a single administrative decision valid in the specified area of use.
The introduction of uniform TSI and a centralized approval process significantly impacted the standardization of railway technical requirements. Rolling stock manufacturers can design vehicles with the entire EU market in mind, rather than adapting to numerous disparate national requirements. Standardization covers aspects such as vehicle gauge, braking systems, cab signaling systems (ERTMS/ETCS), and noise emission requirements, enabling a new TSI-compliant vehicle to more easily gain approval for operation in various countries. From a safety perspective, the directive ensures that all vehicles approved for the market meet common, high standards, verified by independent notified bodies. The role of these bodies remains crucial as they conduct detailed tests and analyses, forming the basis for certification and administrative decisions. Comprehensive technical documentation is also essential: applicants must provide a complete technical dossier, including design descriptions, schematics, calculation and test results, subsystem certificates, and maintenance condition information. This documentation facilitates authorities’ assessment of vehicle compliance and is vital throughout the lifecycle, such as during modernizations or accident investigations.
Directive 2016/797: Harmonized Standards
A cornerstone of the EU railway interoperability system is the catalog of harmonized standards, which serve as practical extensions of the requirements in Directive 2016/797. Applying such a standard provides a presumption of conformity with the essential requirements, simplifying the assessment and certification process for vehicles or their components. For Directive 2016/797, harmonized standards cover a full range of technical issues, including vehicle structural strength (e.g., EN 12663), dynamic parameters and running tests (EN 14363), fire protection (EN 45545), electronic equipment (EN 50155), welding construction and quality (EN 15085), and safety management systems (e.g., EN 50126 for RAMS aspects). The list of currently harmonized documents is published in the Official Journal of the EU and regularly updated, so manufacturers and component suppliers should routinely verify whether the standards they use are still listed. While using harmonized standards is not mandatory, it significantly accelerates approval procedures and facilitates demonstrating compliance with the directive’s essential requirements, which is particularly important for complex projects, such as new locomotive types or modernizations involving multiple technical areas.
Practical Applications
Directive 2016/797 has transformed railway approval realities. For instance, the modern multi-system Siemens Vectron locomotive received a single authorization to place on the market valid simultaneously in several EU countries, allowing operators to use the same vehicle in international traffic without separate approval procedures in each country. Similarly, standard rolling stock components, such as wagon bogies or ETCS radio devices, after obtaining a European declaration of conformity, can be used by various vehicle manufacturers across the Union. This procedural unification saves time and costs and fosters competition among manufacturers and suppliers. Central registers, such as the European Register of Authorised Types of Vehicles (ERATV), have been established to collect information on issued authorizations and facilitate their mutual recognition by member states.
Directive 2016/797 introduced a unified framework for authorizing railway vehicles and infrastructure on the EU market, marking a milestone in building the Single European Railway Area. Thanks to interoperability, operators can more easily use rolling stock in international traffic, and manufacturers have simplified access to an expanded market. Standardizing technical requirements through TSI has eliminated many barriers, reducing the time and costs needed for train homologation in different countries. At the same time, a high level of safety is maintained through conformity assessment mechanisms, including a common risk assessment method and oversight by independent notified bodies. For manufacturers, the directive necessitates meticulous documentation and confirmation of compliance with European standards, but in return, their products gain acceptance throughout the EU. For infrastructure managers and passengers, interoperability translates into a coherent, safe, and efficient railway network without “artificial” barriers at national borders. Consequently, Directive 2016/797 forms the legal foundation of a modern, unified railway market where technical innovations can spread more rapidly, and railways become more competitive against other transport sectors.
FAQ: Directive 2016/797
The main goal is to ensure the interoperability of the railway system across the European Union. The directive establishes common technical requirements (including Technical Specifications for Interoperability, TSI) that railway vehicles and subsystems must meet to be approved for operation on networks of different member states without additional technical barriers.
Formally, there is no obligation to use harmonized standards, but using them provides a presumption of conformity with the directive’s requirements. In practice, this significantly speeds up the conformity assessment procedure and helps avoid additional verifications or tests, which is particularly important when designing and producing new rolling stock.
The manufacturer or other responsible entity submits the vehicle along with the necessary technical documentation for assessment by an independent notified body. This body verifies whether the vehicle meets TSI requirements and national regulations (open points in TSI). After receiving a positive opinion, the European Union Agency for Railways (ERA) issues the authorization to place the vehicle on the market. It collaborates with the national safety authority (in Poland – the Office of Rail Transport).
If a modernization introduces changes affecting interoperability requirements (e.g., braking systems, safety, network compatibility), it is necessary to re-demonstrate compliance with the relevant TSI and obtain the appropriate certificates. Minor repairs that do not alter the vehicle’s characteristics regarding interoperability usually do not require a full re-assessment procedure.
The directive allows for ‘derogations’ in certain exceptional situations (e.g., historical rolling stock, lines with specific parameters). However, obtaining a derogation requires approval from the relevant authorities and must be supported by an analysis showing that it does not compromise safety or hinder interoperability on the EU railway system scale.