TSI Control-Command and Signalling

Scope

Technical Specification for Interoperability covering the trackside and on-board control-command and signalling subsystems of the EU rail system, setting the mandatory requirements for ERTMS/ETCS, RMR/GSM-R and the applicable ERA specification sets. It is the legal basis for CCS subsystem and vehicle authorisation, used by infrastructure managers, railway undertakings, suppliers and notified bodies. Repeals Regulation (EU) 2016/919; amended by Implementing Regulation (EU) 2026/693 (new testing specifications and transitional measures, applicable from 5 May 2026).

The Technical Specification for Interoperability for Control-Command and Signalling, Regulation (EU) 2023/1695, sets the mandatory technical requirements for the trackside and on-board control-command and signalling subsystems of the EU rail system, centred on the European Rail Traffic Management System (ERTMS). It requires conformity with the European Train Control System (ETCS) and Radio Mobile Communication (currently GSM-R, migrating to FRMCS), referencing the detailed UNISIG/ERA SUBSET specifications and the EIRENE and FRMCS functional requirement specifications listed in its Annex A as the single set of specifications applicable at each baseline. As the legal basis for CCS subsystem and vehicle authorisation, it is applied by infrastructure managers when authorising trackside ERTMS installations, by manufacturers and railway undertakings when authorising on-board units, and by notified bodies performing EC verification. It repealed the earlier Regulation (EU) 2016/919 and was itself amended by Implementing Regulation (EU) 2026/693, which introduced new testing specifications and transitional measures applicable from 5 May 2026. Because ERTMS specifications evolve through defined baselines, the TSI's Annex A specification set is periodically updated, and current and prior baselines coexist during transition periods managed through the Regulation's transitional provisions.