Requirements on track side Control Command and Signalling system

Definitions and rules

When developing a new safety critical Control Command and Signalling system (CCS-system) e.g. interlocking, train protection or automatic level crossing, the system has to be safe. To demonstrate the safety the applicant can use the standards EN 50126, EN 50128 and EN50129. This means that the system is developed according to a specified process, the safety demonstration will be reported in a "safety case". An independent safety assessor (ISA) shall assess the safety demonstration and make an assessment report.

The Swedish Transport Agency guide "Requirement on the content of an assessment report" sets the requirements on the content and structure of the assessment report. The ISA and his/her task has to be approved by the Swedish Transport Agency for each project. To avoid unnecessary work the applicant should ask for the Swedish Transport Agency's approval of the ISA and his/her task early in the project. The requirement on the ISA is that he/she must be independent, both personally and organizational, to the project that will be assessed. Also the ISA must have good knowledge in the process and techniques of developing safety critical systems.

Radio Communication

All infrastructure for railway, metro and trams shall have a radio system installed for communication with the vehicles. For railway networks a GSM-R system has to be installed. This requirement is not applicable to suburban networks, networks only for the infrastructure managers with their own gods and for historical networks.

Train protection system (ATP)

When infrastructures with ATP installed are extended or modified ATP must be installed also on the new or modified part of the infrastructure.

The Swedish railway net has a common national train protection system, ATC2 (also called class B-system). During the next decades the ATC2-system will be replaced by ERTMS, which is the new common system to be used in the European Union

The European Union has designated corridors where the nations have to install ERTMS. The corridor in Sweden is  a part of the Scandinavian - Mediterranean Corridor. This corridor is required to have ERTMS installed by 2030 (according to 1315/2013), but more detailed requirements are presented in the implementing regulation 2017/6 on the European Rail Traffic Management System European deployment plan. When installing the train protection part of a CCS-system on a high speed line or sometimes when a system is uppgraded ERTMS is mandatory.

Sweden has has a National Implementation plan of when the Swedish railways will be replaced by ERTMS.

There are no direct requirements to install a train protection (ATP) system on new networks for trams, metros, suburban trains or networks only for the infrastructure managers own goods. However there is a generic requirement to keep the level of safety when we authorise a new or modified infrastructure. When extend, upgrade or renew an infrastructure which has an ATP-system you should install ATP also on the modified part of the infrastructure. If the network to be modified has no ATP-system the operational rules of the modified network may be affected by the modification.

Applied TSIs

The following TSI is valid for the subsystems control command and signalling. It states the requirements of ERTMS and GSM-R:

When a sub system, partly or fully covered by TSI:s, are authorised the applicant must engage a notified body (NoBo). The NoBo must assess the fullfillment of the requirements in the relevant TSI:s. An application should also be sent to the Swedish Transport Agency that can decide which national rules that has to be applied. When modifying an existing sub system the Swedish Transport Agency will decide which functions that will be assessed and if a new authorisation is needed.

The authorisation may also be done in different phases, see page for authorisation of infrastructure for railway, metro and tram.

The Swedish Transport Agency and the European Rail Agency (ERA) have issued a number of technical documents and guide lines to facilitate the application of the TSIs and authorisation of rail infrastructure. Below you find the guidelines regarding Command Control and Signalling subsystems.

The European Union Agency for Railways (ERA) has made a guideline and template for Notified Body to use when indicating restrictions, conditions and added functions in their certificates: Restrictions and conditions and added functions

National requirements

A TSI-compliant subsystem shall fulfill the TSI requirements and notified national requirements. The national requirements shall be assessed by a Designated body (DeBo), the applicant also has to engage the Debo in the authorisation process. The Debo shall write a certificate saying that the subsystem fulfills the requirements.

At the moment the Swedish Transport Agency does not see the need to notify any national requirements.

Safe integration on the on board to the track side Control Command and signalling subsystems

When the Swedish Transport Agency makes an authorisation of an infrastructure we will check that the network including the CCS-system fulfills the essential requirements. We will check the safe integration between the track side and the on board CCS-system. The integration between the track side and the on board systems shall be assessed for all types of on board system operating on the network. All functions which are set according to the essential requirements are assessed according to both TSI and national requirements. The assessor (ISA) shall be approved by the Swedish Transport Agency.

The vehicles operating on a network have some types and versions of on board CCS-systems. To make the authorisation of the infrastructure with a new or upgraded CCS-system the applicant shall demonstrate both safety and safe integration to these on board CCS-systems operating on the infrastructure. This is handled with ETCS System Compatibillity (ESC) and Radio System Compatibility (RSC)

ETCS System Compability/ Radio System Comnpability

Infrastructure managers are responsible to develop parameters and test cases for ESC and RSC but also get these parameters and test cases authorized  by ERA. More information about system compatibility and wich parameters that have been authorized by ERA can be seen on the ERA website. If the system has to be changed or modified the infrastructure manager has to make sure that the change or modification does not affect the parameters and the test cases.

The Swedish Transport Agency used to approve the compatibility between a trackside system and the onboard system. Which combinations of trackside and onboard systems that have been authorized before the procedure with ESC and RSC can be seen here: Sammanställning av godkänd integration mellan ERTMS mark- och ombordsystem (link in Swedish)

How ESC/RSC are affecting the authorization of rail vehicles are described at: Requirements on On Board Control Command and Signaling systems (CCS)

ERA trackside approval

Before an applicant begins any call for tender of a track side ERTMS system the relevant documentation has to be sent to ERA for approval. This has to be done since ERA has to control that all of the planned technical solutions fullfills the requirements in all of the relevant TSI:s. In that way the interoperabillity are controlled in the planned system. More detailed information can be found at ERA:s web site: ERTMS trackside approval