ERA Railway Terminology Collection

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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Latest release: 1 April 2025

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Starting with "O" (176)

Disclaimer
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
Orientation	International Standard	ISO	ISO 5660-1:2015(en) Reaction-to-fire tests — Heat release, smoke production and mass loss rate — Part 1: Heat release rate (cone calorimeter method) and smoke production rate
OS	Operation	TSI	Commission Implementing Regulation (EU) 2019/773 of 16 May 2019 on the technical specification for interoperability relating to the operation and traffic management subsystem of the rail system within the European Union and repealing Decision 2012/757/EU
OS	ERTMS	Technical Document	ERTMS/ETCS - Glossary of Terms and Abbreviations - version : 4.0.0 - date 05/07/2023
OS	ERTMS	ERA Technical Document	Technical Document ERTMS Operational Principles and Rules ERA_ERTMS_OPE_AppA_5 / V 5.0 on 09.04.2019
OSCE	EU Policy	EU Technical Document	Technical document from the Publications Office of the European Union - ‘Style guide’ Coordination Interinstitutional Style Guide - version on 19.04.2022
OSHA	EU Policy	EU Technical Document	Technical document from the Publications Office of the European Union - ‘Style guide’ Coordination Interinstitutional Style Guide - version on 19.04.2022
OSI	EU Policy	EU Technical Document	Technical document from the Publications Office of the European Union - ‘Style guide’ Coordination Interinstitutional Style Guide - version on 19.04.2022
OSJD	Operation	TSI	Commission Implementing Regulation (EU) 2019/773 of 16 May 2019 on the technical specification for interoperability relating to the operation and traffic management subsystem of the rail system within the European Union and repealing Decision 2012/757/EU
OSS	Telematics Applications for Freight	TSI	Commission Regulation (EU) No 1305/2014 of 11 December 2014 on the technical specification for interoperability relating to the telematics applications for freight subsystem of the rail system in the European Union and repealing the Regulation (EC) No 62/2006
OT	EU Policy	EU Technical Document	Technical document from the Publications Office of the European Union - ‘Style guide’ Coordination Interinstitutional Style Guide - version on 19.04.2022
OTD	International Standard	ISO	ISO 22163:2023(en) Railway applications — Railway quality management system — ISO 9001:2015 and specific requirements for application in the railway sector
Other accident	Safety / SSC-SA	Directive	Directive (EU) 2016/798 of the European Parliament and of the Council of 11 May 2016 on railway safety (recast)
Other Cant Deficiency train categories for which the ETCS trackside is configured to provide SSP	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
Other crew members performing safety-critical tasks	Human and Organisational Factor	Directive	Directive 2007/59/EC of the European Parliament and of the Council of 23 October 2007 on the certification of train drivers operating locomotives and trains on the railway system in the Community
Other ETCS requirements (related to existing not interoperable networks)	Interoperability	Decision	Commission Decision of 30 November 2009 on the reference document referred to in Article 27(4) of Directive 2008/57/EC of the European Parliament and of the Council on the interoperability of the rail system within the Community. (2009/965/EC)
Other GSM-R requirements	Interoperability	Decision	Commission Decision of 30 November 2009 on the reference document referred to in Article 27(4) of Directive 2008/57/EC of the European Parliament and of the Council on the interoperability of the rail system within the Community. (2009/965/EC)
Other health and safety requirements	Interoperability	Decision	Commission Decision of 30 November 2009 on the reference document referred to in Article 27(4) of Directive 2008/57/EC of the European Parliament and of the Council on the interoperability of the rail system within the Community. (2009/965/EC)
Other lines	EU Policy	Glossary	Glossary for transport statistics - 5TH EDITION 2019
Other person at a platform	Safety / SSC-SA	Directive	Directive (EU) 2016/798 of the European Parliament and of the Council of 11 May 2016 on railway safety (recast)
Other person not at a platform	Safety / SSC-SA	Directive	Directive (EU) 2016/798 of the European Parliament and of the Council of 11 May 2016 on railway safety (recast)

Certification Scheme
Common Safety Method
Conformity Assessment
Control-Command and Signalling
Data Protection
Energy
Entity in Charge of Maintenance
ERTMS
EU Policy
Freight
Human and Organisational Factor
Infrastructure
International Relations
International Standard
Interoperability
Noise
Operation
Persons with Reduced Mobility
Railway Tunnels
Registers
Regulation
RNE Glossary
Safety / SSC-SA
Sectorial Scheme
Security
SERA_EU Transport
Telematics Applications for Freight
Telematics Applications for Passenger
Vehicles / VA
Withdrawn

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ERA Ontology
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