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ERA Railway Terminology visual v0 featured

ERA Railway Terminology Collection

Last updated: 5 December 2025.

The ERA Railway Terminology Collection gathers terms and abbreviations that are contained in the EU legal framework for railway, technical documents produced by bodies which are engaged in the development of important evolution in the railway system and other relevant glossaries.

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The file you will get by clicking the "Download the full Terminology" button below is in CSV format. To convert it to a readable Excel file:

1. Download the CSV file
2. Open a blank Excel sheet
3. Go to Data → Get Data from CSV → select the CSV file you just downloaded
4. The Excel file will be generated (without any encoding issues)

Starting with "U" (165)

ERA Railway Terminology Collection is a consultation tool, developed to support the sharing of information through the actors involved in running the Single European Railway Area (SERA). The responsibility for the correctness, completeness, accuracy, or reliability of the information in ERA RTC lays upon the authors of the definitions, as they derive from reference documents having their own preparation and approval flow. Users cannot call ERA liable for the use they make of the content. Please consider that when the collection is exported (.csv) and then printed or converted, it becomes uncontrolled.
Term Context Document Type Origin document

Unilateral Approval

International Relations

Convention

Convention concerning International Carriage by Rail (COTIF) Appendix C – Regulations concerning the International Carriage of Dangerous Goods by Rail (RID)

Union

EU Policy

Regulation

Regulation (EU, Euratom) 2024/2509 of the European Parliament and of the Council of 23 September 2024 on the financial rules applicable to the general budget of the Union (recast)

Union entities

Interoperability

Regulation

Regulation EU) 2024/903 of the European Parliament and of the Concil of 13 March 2024 laying down measures for a high level of public sector interoperability across the Union.

Union harmonisation legislation

Single Market Mutual Recognition Conformity Assessment

Regulation

Regulation (EU) 2023/988 of the European Parliament and of the Council of 10 May 2023 on general product safety, amending Regulation (EU) No 1025/2012 of the European Parliament and of the Council and Directive (EU) 2020/1828 of the European Parliament and the Council, and repealing Directive 2001/95/EC of the European Parliament and of the Council and Council Directive 87/357/EEC

Latest release

Union harmonisation legislation

ERTMS

Directive

Directive 2014/53/EU of the European Parliament and of the Council of 16 April 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of radio equipment and repealing Directive 1999/5/EC

Union institution

EU Policy

Regulation

Regulation (EU, Euratom) 2024/2509 of the European Parliament and of the Council of 23 September 2024 on the financial rules applicable to the general budget of the Union (recast)

Union institutions and bodies

Data Protection

Regulation

Regulation (EU) 2018/1725 of the European Parliament and of the Council of 23 October 2018 on the protection of natural persons with regard to the processing of personal data by the Union institutions, bodies, offices and agencies and on the free movement of such data, and repealing Regulation (EC) No 45/2001 and Decision No 1247/2002/EC

Union law

Vehicles / VA

Application Guide

Guidelines for the practical arrangements for the vehicle authorisation process - v. 2.1 on 14/02/2024

Latest release

Union rail system

Interoperability

Directive

Directive (EU) 2016/797 of the European Parliament and of the Council of 11 May 2016 on the interoperability of the rail system within the European Union (recast)

Union rail system

Safety / SSC-SA

Directive

Directive (EU) 2016/798 of the European Parliament and of the Council of 11 May 2016 on railway safety (recast)

Unique identifier

EU Policy

Decision

Commission Decision (EU) 2021/2121 of 6 July 2020 on records management and archives

Unique OP ID

Infrastructure

Regulation

Commission Implementing Regulation (EU) 2019/777 of 16 May 2019 on the common specifications for the register of railway infrastructure and repealing Implementing Decision 2014/880/EU

UNISIG

ERTMS

Glossary

ERTMS Glossary

UNISIG

ERTMS

Technical Document

ERTMS/ETCS - Glossary of Terms and Abbreviations - version : 4.0.0 - date 05/07/2023

UNISIG

Control-Command and Signalling

Application Guide

GUI/CCS TSI/2023 Version 1.0 17/06/2024 Guide for the application of the CCS TSI 2023/1695 In accordance with Article 19(3) of Regulation (EU) 2016/796 of the European Parliament and of the Council of 11 May 2016

Unit

Freight

Glossary

Handbook of scenarios for assessing major chemical accident risks JRC106029 - Ed. 2017

Unit

Vehicles / VA

TSI

Commission Regulation (EU) No 1302/2014 of 18 November 2014 concerning a technical specification for interoperability relating to the rolling stock — locomotives and passenger rolling stock subsystem of the rail system in the European Union

Unit

Noise

TSI

Commission Regulation (EU) No 1302/2014 of 18 November 2014 concerning a technical specification for interoperability relating to the rolling stock — locomotives and passenger rolling stock subsystem of the rail system in the European Union

Unit

Freight

TSI

Commission Regulation (EU) No 321/2013 of 13 March 2013 concerning the technical specification for interoperability relating to the subsystem ‘rolling stock — freight wagons’ of the rail system in the European Union and repealing Decision 2006/861/EC

Unit

International Standard

ISO

ISO 3381:2021(en) Railway applications — Acoustics — Noise measurement inside railbound vehicles