Block System Interface Requirements Synopsis This document mandates the requirements for block systems interfaces between signalling infrastructure and railway operations. Copyright in the s is owned by Rail Safety and Standards Board Limited. All rights are hereby reserved. No (in whole or in part) may be reproduced, stored in a retrieval system, or transmitted, in any form or means, without the prior written permission of Rail Safety and Standards Board Limited, or as expressly permitted by law. Members are granted copyright licence in accordance with the Constitution Agreement relating to Rail Safety and Standards Board Limited. Content approved by: Control Command and Signalling (CCS) Standards Committee on 08 April 2010 and reconfirmed on 13 June 2013 Authorised by on 29 July 2013 In circumstances where Rail Safety and Standards Board Limited has granted a particular person or organisation permission to copy extracts from Railway Group Standards, Rail Safety and Standards Board Limited accepts no responsibility for, and excludes all liability in connection with, the use of such extracts, or any claims arising therefrom. This disclaimer applies to all forms of media in which extracts from s may be reproduced. Published by: Block 2 Angel Square 1 Torrens Street London EC1V 1NY Copyright 2013 Rail Safety and Standards Board Limited
Issue record Issue Date Comments One 07 September 2013 Original document Superseded documents Supply The following Railway Group documents are superseded, in part as indicated: Superseded documents Sections superseded Date when sections are superseded GK/RT0041issue one Track Circuit Block GK/RT0042 issue one Absolute Block GK/RT0051 issue one Single Line Control GK/RT0054 issue one Radio Electronic Token Block GK/RT0060 issue four Block Systems Interface Requirements GK/RT0063 issue one Approach Locking and Train Operated Route Release GK/RT0064 issue one Provision of Overlaps, Flank Protection and Trapping 4 para 1, 7, 5 para 2 07 Dec 2013 5 para 2 sentence 1, 6.4 para 1 & 2, 7 Various refer to impact assessment for details Various refer to impact assessment for details 07 Dec 2013 07 Dec 2013 07 Dec 2013 C5.1.9 Para 1 and C2.3 07 Dec 2013 4.2 para 5 bullet point 2 07 Dec 2013 4.6, 4.9.2a) 07 Dec 2013 Other parts of GK/RT0041 issue one, GK/RT0042 issue one, GK/RT0051 issue one, GK/RT0054 issue one, GK/RT0060 issue four, GK/RT0063 issue one, are superseded by GK/RT0077 issue one, Ground Frames and Shunters Releases. Remaining parts of the superseded documents are withdrawn and cease to be in force as of 07 December 2013. The authoritative version of this document is available at www.rgsonline.co.uk. Uncontrolled copies of this document can be obtained from Communications,, Block 2 Angel Square, 1 Torrens Street, London, EC1V 1NY, telephone 020 3142 5400 or e-mail enquirydesk@rssb.co.uk. Other Standards and associated documents can also be viewed at www.rgsonline.co.uk. Page 2 of 21
Contents Section Description Page Part 1 Purpose and Introduction 4 1.1 Purpose 4 1.2 Introduction 4 Part 2 Block System Requirements 6 2.1 Compatibility requirements for block systems 6 2.2 Requirements for movement authorities 8 2.3 Requirements for single line instruments, single line tokens and one-train staffs 12 2.4 Requirements for radio electronic token block (RETB) cab display units and tokens 13 Part 3 Application of this Document 16 3.1 Application infrastructure managers 16 3.2 Application railway undertakings 17 3.3 Health and safety responsibilities 17 Definitions 18 References 21 Page 3 of 21
Part 1 Purpose and Introduction 1.1 Purpose 1.1.1 This document mandates the requirements for block systems interfaces between signalling system infrastructure and railway operations. 1.1.2 The requirements are applicable to routes signalled using lineside signalling in accordance with GK/RT0045: Lineside Signals, Indicators and Layout of Signals, and are not applicable to routes solely operated using the European Rail Traffic Management System (ERTMS). 1.2 Introduction 1.2.1 Background 1.2.1.1 Signalled movement authorities are generated by the infrastructure manager and displayed to railway undertakings at the signalling system interface by lineside signals and indicators (see GK/RT0045 Lineside Signals, Indicators and Layout of Signals). 1.2.1.2 Block systems are the means by which the signalling system regulates the generation of movement authorities so that only one train is authorised in a block section at a time (with some specific exceptions where shunting or permissive working is allowed). 1.2.1.3 Depending on the type of block system used, movement authorities at some locations can include additional signalling system interfaces (for example, single line tokens). 1.2.1.4 The railway between two adjacent block sections may be designated as station limits, which may comprise one or more signal sections controlled by the same signal box as the adjacent block sections. Guidance on station limits is set out in Appendix A of GK/GN0655 Guidance on. 1.2.1.5 Signallers are responsible for authorising train movements in accordance with the GK/RT8000 Rule Book. This includes the rules for: a) Operation of block systems in accordance with the relevant block signalling regulations and any local operating instructions. b) Controlling train movements within station limits. c) Operation of the signalling control and display system. d) Communication with train crew. 1.2.1.6 Train crew are responsible for controlling train operations in accordance with the GE/RT8000 Rule Book. This includes the rules for: a) Controlling train movements in accordance with the movement authorities received, using their route knowledge and traction knowledge. b) Operating signalling equipment where it is specifically provided for use by train crew. c) Communication with signallers. Page 4 of 21
1.2.2 Principles 1.2.2.1 Irrespective of the type of block system used, there are two key block principles associated with the interface between the infrastructure manager and railway undertakings: a) Except where permissive working or shunting is specifically permitted, each block section is reserved for one train at a time, and b) Where permissive working is permitted, a train may only enter an occupied block or signal section under the authority of a position light signal, semaphore subsidiary signal or semaphore shunting signal. 1.2.3 Related requirements in other documents 1.2.3.1 The following s contain requirements that are relevant to the scope of this document: GE/RT8075 GI/RT7033 GK/RT0044 GK/RT0045 GK/RT0077 GK/RT0192 AWS and TPWS Interface Requirements Lineside Operational Safety Signs Permissive Working Lineside Signals, Indicators and Layout of Signals Ground Frames and Shunters Releases Level Crossing Interface Requirements 1.2.4 Supporting document 1.2.4.1 The following Railway Group document supports this : GK/GN0655 Guidance on Page 5 of 21
Part 2 Block System Requirements 2.1 Compatibility requirements for block systems 2.1.1 Compatibility between block systems and train operations 2.1.1.1 Before any new or changed infrastructure or rolling stock (including lineside and / or on-board control, command and signalling equipment) is brought into use, it is necessary to check that it is compatible with the infrastructure and rolling stock assets and operations on the routes on which it is to be used. 2.1.1.2 GE/RT8270 sets out the requirements and responsibilities for the assessment of compatibility between rolling stock and infrastructure assets, including control, command and signalling equipment and their operations. It sets out the arrangements by which the assessment of compatibility is undertaken and identifies those responsible for managing that assessment. 2.1.1.3 This document mandates the specific requirements for the assessment of compatibility for the different types of block systems. 2.1.1.4 The assessment shall check that the block system is compatible with the movement authorities required by railway undertakings, including: a) Passenger and non-passenger movements. b) Permissive working. c) Shunting. 2.1.1.5 The assessment shall check that the signalling system is compatible with the risk mitigation measures that will be put in place by railway undertakings, including: a) Compatibility between the omission of opposing route locking on shunt class routes and the shunting that will take place. b) Compatibility between approach locking release times and the time required for trains to stop when a movement authority is shortened or withdrawn. c) Compatibility between the length of overlaps (including reduced and restricted overlaps), and the overrun risk that needs to be controlled. 2.1.1.6 The assessment shall check the method of displaying movement authorities at the lineside using: a) Worked signals (see GK/RT0045). b) Lineside signs and buffer stops used as signals (see GK/RT0045). c) Lineside operational signs (see GI/RT7033). 2.1.1.7 The assessment shall check the risk of driver misunderstanding where AWS equipment is not suppressed on bi-directional lines (see GE/RT8075 and GI/RT7033). 2.1.1.8 The assessment shall check that, where required, facilities are provided for authorised railway personnel to either: a) Verify and report train completeness to the signaller at the end of block sections and at token control points, or Page 6 of 21
b) On lines fitted with radio electronic token block (RETB), report train location to the signaller. 2.1.1.9 The assessment shall check that, where token or one-train staff systems are used, the requirement for token or one-train staff exchange on single lines is compatible with train operations: a) Using direct transfer of the single line token / one-train staff between the signaller and the driver. b) Where an auxiliary token instrument or one-train staff instrument is provided for drivers to obtain and / or return tokens without requiring direct transfer between the signaller and the driver. c) Where a no signaller token instrument is provided as part of a no signaller token block or no signaller token block remote system. 2.1.1.10 The assessment shall check that, where a signal box controlling two adjacent single line sections can be switched out: a) The applicability of each long section token / one-train staff and short section token / one-train staff is compatible with train operations, and b) The different arrangements for token exchange / one-train staff exchange when an intermediate signal box is opening and closing is compatible with train operations. 2.1.1.11 The assessment shall check that the risk mitigation measures are sufficient to reduce risk to an acceptable level: a) At the transition between lines worked in accordance with different block regulations. b) When either a token or one-train staff is carried beyond the end of the applicable single line section. c) To prevent the insertion of a token or one-train staff in the wrong single line instrument. d) To manage a discrepancy between the number of trains in each direction and the number of available tokens. 2.1.1.12 The assessment shall check that the facilities required to support voice communication between the driver and the signaller are in accordance with the GE/RT8000 Rule Book at the following locations: a) Stop signals. b) Token control points. c) At other locations where there is an anticipated or known requirement for communication. 2.1.1.13 The assessment shall check that the risk mitigation measures necessary to control the risk accruing from secondary hazards introduced by the fail-safe design of the interlocking that result in degraded situations (for example, hand signalling), are sufficient to reduce risk to an acceptable level. Page 7 of 21
2.1.1.14 The assessment shall check, for RETB systems: a) The functionality of voice and data radio communication systems, including coverage. b) The means of train identification that is compatible with the train reporting system. c) The procedures for testing the on-train equipment prior to a train operating over a route signalled using the RETB system. 2.2 Requirements for movement authorities 2.2.1 Track circuit block 2.2.1.1 Except where signalling facilities are specifically provided to facilitate permissive working, as set out in GK/RT0044, the track circuit block system shall only permit one train in a signal section at a time. 2.2.1.2 The requirements for provision of signals on lines operated in accordance with the track circuit block regulations are set out in GK/RT0045. 2.2.2 Absolute block (including interlocked absolute block) 2.2.2.1 The signalling system shall only permit one train in an absolute block section, intermediate block section or station limits signal section at a time, except where signalling facilities are specifically provided to facilitate permissive working, as set out in GK/RT0044. 2.2.2.2 The requirements for provision of signals on lines operated in accordance with the absolute block regulations are set out in GK/RT0045, including signals associated with: 2.2.3 Tokenless block a) Absolute block sections, and b) Station limits. 2.2.3.1 The signalling system shall: a) Only permit one train in a tokenless block section at a time, and b) Only permit one train in each station limits signal section at a time, except where signalling facilities are specifically provided to facilitate permissive working, as set out in GK/RT0044. 2.2.3.2 The requirements for provision of signals on lines operated in accordance with the tokenless block regulations are set out in GK/RT0045, including signals associated with: a) Tokenless block sections, and b) Station limits. 2.2.4 Electric token block (excluding no signaller token systems) 2.2.4.1 The signalling system shall: a) Only permit one train in an electric token block section at a time, and Page 8 of 21
b) Only permit one train in each station limits signal section at a time, except where signalling facilities are specifically provided to facilitate permissive working, as set out in GK/RT0044. 2.2.4.2 There shall be a signal box at each end of the token section to facilitate token exchange. 2.2.4.3 The commencement of electric token block working shall be indicated using either one of the following: a) A section signal and, where the previous block section is operated by a nontoken method, a lineside sign which displays the words Commencement of token working. b) A stop board which includes the words Obtain token before proceeding. c) A lineside operational sign which displays the words Commencement of token section. 2.2.4.4 The termination of electric token block working shall be indicated using either: a) A home signal and, where the previous block section is operated by a nontoken method, a lineside sign which displays the words End of token section, or b) A stop board which includes the words End of token section. 2.2.4.5 Where a stop board is provided to protect station limits, the wording on the stop board shall describe the requirements for passing the stop board. 2.2.4.6 Where a lineside operational sign is provided to protect station limits, the wording on the sign shall describe the method of working beyond the sign, including any provision for permissive working within station limits. 2.2.4.7 The requirements for provision of signals on lines operated in accordance with the electric token block regulations are set out in GK/RT0045, including signals associated with: a) Electric token block sections, and b) Station limits. 2.2.5 No signaller token block 2.2.5.1 The signalling system shall only permit one train in each no signaller token block section and station limits signal section at a time. 2.2.5.2 Each no signaller token block section shall include a signal box to facilitate token exchange at one end of the single line section, and a token control point to facilitate token exchange at the remote end of the single line section. 2.2.5.3 The commencement of no signaller token block working shall be indicated using either one of the following: a) A section signal in combination with a lineside operational sign which displays the words Commencement of token section. b) A stop board which displays the words Obtain token before proceeding. c) A lineside operational sign which displays the words Commencement of token section. Page 9 of 21
2.2.5.4 The termination of no signaller token block working shall be indicated using a lineside operational sign which displays the words End of token section. 2.2.5.5 Where a stop board is provided to protect station limits, the wording on the stop board shall describe the requirements for passing the stop board. 2.2.5.6 Where a lineside operational sign is provided to protect station limits, the wording on the sign shall describe the method of working beyond the sign, including any provision for permissive working within station limits. 2.2.5.7 The requirements for provision of signals on lines operated in accordance with the no signaller token block regulations are set out in GK/RT0045, including signals associated with: a) No signaller token block sections, and b) Station limits. 2.2.6 No signaller token block remote 2.2.6.1 The signalling system shall only permit one train in each no signaller token block remote section at a time. 2.2.6.2 There shall be a token control point to facilitate token exchange at each end of the no signaller token block remote section. 2.2.6.3 The signaller shall supervise the correct operation of the no signaller token block remote section. 2.2.6.4 The commencement of no signaller token block remote working shall be indicated using either one of the following: a) A section signal in combination with a lineside operational sign which displays the words Commencement of token section. b) A stop board which displays the words Obtain token before proceeding. c) A lineside operational sign which displays the words Commencement of token section. 2.2.6.5 The termination of no signaller token block remote working shall be indicated using a lineside operational sign which displays the words End of token section. 2.2.6.6 The requirements for provision of signals on lines operated in accordance with the no signaller token block remote regulations are set out in GK/RT0045. 2.2.7 One-train system with staff 2.2.7.1 The one-train system with staff shall only permit one train in a one-train staff section at a time. 2.2.7.2 There shall be a signal box or token control point at one end of the one-train system with staff section to facilitate exchange of the one-train staff. 2.2.7.3 Where a token control point is provided, one of the following one-train staff instruments shall be provided for use by authorised railway undertaking personnel, either: a) A one-train staff receptacle located at a secure token control point, or b) A one-train staff controller that is released by the signaller. Page 10 of 21
2.2.7.4 In the outward direction, the commencement of one-train staff working shall be indicated using either one of the following: a) A section signal in combination with a lineside operational sign which displays the words Commencement of staff section. b) A stop board which includes the words Obtain staff before proceeding. c) A lineside operational sign which displays the words Commencement of staff section. 2.2.7.5 In the outward direction, the termination of one-train staff working shall be indicated using a lineside operational sign which displays the words End of staff section. 2.2.7.6 In the return direction, the commencement of one-train staff working shall be indicated using a lineside operational sign which displays the words Commencement of staff section. 2.2.7.7 In the return direction, the termination of one-train staff working shall be indicated by a home signal in combination with a lineside operational sign which displays the words End of staff section. 2.2.7.8 Further requirements for provision of signals on lines operated in accordance with the one-train working regulations are set out in GK/RT0045. 2.2.8 One-train system without staff 2.2.8.1 The one-train system without staff shall only permit one train in a one-train staff section at a time. 2.2.8.2 In the outward direction the termination of one-train system without staff working shall be indicated using a lineside operational sign which displays the words End of One-train section. 2.2.8.3 In the return direction, the commencement of one-train section without staff working shall be indicated using a lineside operational sign which displays the words Commencement of One-train section. 2.2.8.4 Further requirements for provision of signals on lines operated in accordance with the one-train working regulations (without staff) are set out in GK/RT0045. 2.2.9 Radio electronic token block (RETB) 2.2.9.1 Except where permissive working is allowed, as set out in GK/RT0044, the RETB system shall only permit one train in a token section at a time. 2.2.9.2 The commencement and termination of RETB working shall be indicated using either: a) A stop board, or b) A stop signal associated with a lineside operational sign. 2.2.9.3 The stop board or lineside operational sign shall display the place name and the following wording Stop Obtain token and permission to proceed. 2.2.9.4 Where a long-section token covers more than one token section, a yellow coloured lineside operational sign shall be provided beneath the stop board(s) at the end of intermediate token exchange points located within the long section token section. The lineside operational sign shall display the following wording, Drivers in Possession of Long Section Token May Proceed. Page 11 of 21
2.2.9.5 A train clear marker sign shall be provided a train length beyond each token exchange point. 2.2.9.6 Channel change markers shall be provided to indicate where the driver is required to change radio channel. The number displayed on the channel change marker shall correspond with the radio channel that the driver is required to select to maintain optimum radio coverage. 2.2.9.7 Determination of train position shall be by spoken messages between the driver and the signaller supported by the issue and return of electronic tokens to and from trains. 2.3 Requirements for single line instruments, single line tokens and onetrain staffs 2.3.1 Token sections: requirements for single line instruments and tokens 2.3.1.1 Regardless of the number of single line instruments associated with a single line section, it shall only be possible to release one token at a time. 2.3.1.2 Where a worked signal is provided at the commencement of the single line section, the signal OFF aspect shall only be displayed when a token has been removed from the single line instrument associated with that signal. 2.3.1.3 For each single line section, tokens (including long section and short section tokens) shall be: a) Permanently marked with the name of the single line section that they apply to, and b) Distinctly configured for the single line section that they apply to. 2.3.1.4 All single line instruments and associated mechanical locks shall be configured to prevent the insertion of a token or one-train staff that belongs to an adjacent single line section. 2.3.1.5 Where a token control point is provided to exchange tokens other than at a signal box, an auxiliary token instrument shall be provided for operation by authorised railway undertaking personnel. 2.3.1.6 Where a token control point is provided to exchange tokens at the end of a single line where there is no signal box, a no signaller token instrument shall be provided for operation by authorised railway personnel. 2.3.2 One-train staff sections: requirements for one-train staff instruments and staffs 2.3.2.1 For each one-train staff section, the one-train staff (including long section and short section staffs) shall be: a) Permanently marked with the name of the single line section that it applies to, and b) Distinctly configured for the single line section it applies to. 2.3.2.2 All one-train staff instruments and associated mechanical locks shall be configured to prevent the insertion of a one-train staff or token that belongs to an adjacent single line section. Page 12 of 21
2.4 Requirements for radio electronic token block (RETB) cab display units and tokens 2.4.1 Cab display units 2.4.1.1 Trainborne cab display units shall: a) Be identified by a unique number, allocated by the infrastructure manager, and which is clearly visible to the driver. b) Only respond to incoming data communications containing the unique number. c) Include the unique number in all outgoing radio communications. d) Incorporate an alphanumeric display on which the identity of the electronic token currently held (and, if required, the token for the next section) is clearly visible. e) Incorporate a secure key switch so that the receipt and return of tokens is only possible if the key is inserted in the operating position. The key shall be captive within the cab display unit when turned to the operating position. f) Have a receive function that, when operated, allows an electronic token to be received from the signalling control centre. g) Have a send function that, when operated, allows either: i) An electronic token to be returned to the signalling control centre, or ii) The cab display unit identity to be entered into the interlocking 2.4.2 Radio system requirements h) Have an audible indication of token exchange taking place. i) Have a voice communications facility that permits the audio level of incoming voice communications to be adjusted. 2.4.2.1 The radio system shall: a) Be capable of carrying voice and data communications between the signalling control unit and cab display units and any other radios provided for operational purposes within the RETB area. b) Be free from interference with other systems. c) Provide sufficient coverage for voice and data communications for the safe movement of trains at the following locations: i) At token exchange points. ii) iii) iv) At, and on the approach to, automatic level crossings that are remotely monitored by the signaller (see GK/RT0192). At other locations where communication is required between the signaller and driver. At channel change points. d) Be capable of use in emergencies. Page 13 of 21
2.4.3 Tokens e) Be compatible with the radio infrastructure for train radio on the route. f) Be configurable to permit the signaller to disable any part of the radio system that becomes defective. 2.4.3.1 The infrastructure manager shall only issue the following types of tokens to railway undertakings: a) Test token. b) Short section token. c) Long section token for movements associated with two or more successive token sections. d) Shunting token for shunting purposes. e) Permissive token for permissive working. 2.4.3.2 The issue of the following tokens shall initiate a distinctive display on the cab display unit: a) A token for a wrong direction move on a double line. b) A token for a wrong direction move at a passing loop on a single line. c) A token for a movement into a siding at a token control point. d) A token for a calling-on movement into an occupied section. 2.4.3.3 Location names used in token displays shall be chosen to avoid ambiguity and to guard against misinterpretation. 2.4.4 Token issue, token return and token exchange functions 2.4.4.1 Token issue shall require all of the following: a) Co-operation between the signaller and the driver. b) Take place only when the cab display unit is in an operational condition. c) The exchange of securely coded data between the signalling control centre and the train, and the transmission of a securely coded electronic token from the signalling control centre to the train. 2.4.4.2 On completion of token issue: a) The cab display unit shall display the token held and the name of the token section to which the token applies, and b) The signaller s display system shall display the issue of the electronic token. 2.4.4.3 Token return shall require all of the following: a) Co-operation between the signaller and the driver, and b) Take place only when the cab display unit is in an operational condition. Page 14 of 21
2.4.4.4 On completion of token return: a) The cab display unit shall be blank after a token is returned and before the next token is received, and b) The signaller s display system shall only show the train identity. 2.4.4.5 Token exchange shall: a) Combine the functions of token return and token issue into one single function. All the requirements applicable to token return and token issue shall be satisfied in order for token exchange to be performed, and b) Require the exchange of securely coded data between the signalling control centre and the train, and the transmission of the securely coded electronic token from the signalling control centre to the train. 2.4.4.6 On completion of token exchange: 2.4.5 Train clear function a) The cab display unit shall display the token held and the name of the token section to which the token applies, and b) The signaller s display system shall display the issue of the electronic token. 2.4.5.1 Train clear shall take place: a) When the rear of the train has cleared the limit of the passing loop, station area, or other location where token issue has taken place, and b) In response to a verbal message from the driver. 2.4.5.2 Train clear shall be indicated on the signaller s display, but the electronic token on the cab display unit shall remain unchanged. 2.4.6 Radio number clear 2.4.6.1 Radio number clear shall remove a radio number from the RETB interlocking: 2.4.7 Train identities a) When a train is cleared from the running line (for example, at a siding), and b) Automatically by the token return procedure when a train on a running line returns a token prior to leaving the RETB controlled area. 2.4.7.1 Entry of train identity (the unique number of the cab display unit) into the interlocking shall require the co-operation of the driver and signaller. 2.4.8 System performance 2.4.8.1 The RETB system shall be designed so that no credible infrastructure sub-system failure or rolling stock sub-system failure results in the irregular issue or return of a token. Page 15 of 21
Part 3 Application of this Document 3.1 Application infrastructure managers 3.1.1 Scope 3.1.1.1 The requirements in Parts 2 and 3 of this document applies to all work that affects block systems, whether new or alteration, except that action to bring existing block systems into compliance with this standard is not required, provided that they were compliant with the standards applicable at the time that they were brought into service. 3.1.1.2 When it is known, or becomes known, that existing block systems do not comply with the requirements of this document, action to bring them into compliance is required when the block system is upgraded. Otherwise it is permissible for the block system equipment to be renewed on a like-for-like basis, commensurate with the standards that were in force at the time of their original installation. 3.1.1.3 It is permissible for the infrastructure manager to designate specific infrastructure projects, ongoing when this document comes into force, for which compliance with the requirements of this document applicable to the design, construction and commissioning of new or altered infrastructure is not mandatory. When designating such projects, the infrastructure manager shall consider: a) Its responsibilities under its current safety authorisation. b) The stage reached by the project at the time this document comes into force (for example, approval in principle). c) Whether compliance is necessary to ensure compatibility with other parts of the infrastructure. d) Whether compliance is necessary to facilitate safe interworking having regard to changes to related requirements mandated on another infrastructure manager or a railway undertaking. e) The economic impact of compliance, but subject to its current safety authorisation in relation to the infrastructure in question. 3.1.1.4 Action to bring existing block systems into compliance with the requirements of this document is not required. 3.1.2 Exclusions from scope 3.1.2.1 There are no exclusions from the scope specified in 3.1.1 for infrastructure managers. 3.1.3 General compliance date for infrastructure managers 3.1.3.1 This comes into force and is to be complied with from 07 December 2013. 3.1.3.2 After the compliance dates or the date by which compliance is achieved if earlier, infrastructure managers are to maintain compliance with the requirements set out in this. Where it is considered not reasonably practicable to comply with the requirements, authorisation not to comply should be sought in accordance with the s Code. 3.1.4 Exceptions to general compliance date 3.1.4.1 There are no exceptions to the general compliance date specified in 3.1.3 for infrastructure managers. Page 16 of 21
3.2 Application railway undertakings 3.2.1 Scope 3.2.1.1 The requirements of this document apply to all work that affects radio electronic token block (RETB) equipment on vehicles, whether new or modified. 3.2.1.2 The requirements of this document apply to all new and existing equipment used for RETB. 3.2.1.3 When vehicles are undergoing major modification in an unrelated subject area, then the requirements of this document are applicable. 3.2.1.4 Action to bring existing RETB equipment into compliance with the requirements of this document is not required. 3.2.1.5 Where it is known, or becomes known, that existing RETB equipment does not comply with the requirements of this document action to bring them into compliance is required as follows: 3.2.2 Exclusions from scope a) When a block system is modified, and b) When a block system is renewed as a whole. 3.2.2.1 There are no exclusions from the scope specified in 3.2.1 for railway undertakings. 3.2.2.2 The requirements in the document are not applicable to the following types of vehicles: a) Possession-only rail vehicles, and b) General Contract of Use (GCU) wagons. 3.2.3 General compliance date for railway undertakings 3.2.3.1 This comes into force and is to be complied with from 07 December 2013. 3.2.3.2 After the compliance dates or the date by which compliance is achieved if earlier, railway undertakings are to maintain compliance with the requirements set out in this. Where it is considered not reasonably practicable to comply with the requirements, authorisation not to comply should be sought in accordance with the s Code. 3.2.4 Exceptions to general compliance date 3.2.4.1 There are no exceptions to the general compliance date specified in 3.2.3 for railway undertakings. 3.3 Health and safety responsibilities 3.3.1 Users of documents published by are reminded of the need to consider their own responsibilities to ensure health and safety at work and their own duties under health and safety legislation. does not warrant that compliance with all or any documents published by is sufficient in itself to ensure safe systems of work or operation or to satisfy such responsibilities or duties. Page 17 of 21
Definitions Absolute block section The line between the last stop signal (that is to say, the section signal or intermediate block home signal) controlled from one signal box to the first stop signal (that is to say, the home signal) controlled by the next signal box in the same direction of travel. The section signal OFF aspect is the authority to enter the block section. Approach locking The locking of any route from a signal, when the driver may have seen an OFF aspect at the signal, or has seen an aspect at a previous signal that would indicate to the driver that the former signal is displaying a proceed aspect. If the signal is replaced to danger, the approach locking prevents the immediate release of the route because it is possible that an approaching train may be unable to stop. Authorised railway personnel A person employed by a railway undertaking or infrastructure manager who is specifically authorised to operate signalling equipment. Auxiliary token instrument A supplementary token instrument located outside the signal box and used by authorised railway personnel to facilitate prompt token exchange. Block section The term block section describes a section of line that is operated in accordance with the relevant block regulations, either between two signal boxes, between a signal box and a token control point worked by train crew, or by one signal box (intermediate block section only). A block section extends from the section signal of the sending signal box or token control point to the first home signal of the next signal box or token control point. Cab display unit A device in the driving cabs of traction units, which is used to receive and return coded electronic tokens and display electronic tokens issued to it. Electric token block section A section of single line extending, in each direction of travel, between the last stop signal (that is to say, the section signal) controlled from one signal box to the first stop signal (that is to say, the home signal) controlled by the next signal box. The electric token is the prime authority to enter the block section. Electronic token A token that is issued to and returned from a cab display unit in the form of securely encoded data transmitted over a data system, which has no physical representation. ETCS European Train Control System. Home signal A stop signal that controls the exit from a block section. Interlocked absolute block section A section of single line extending, in each direction of travel, between the last stop signal (that is to say, the section signal) controlled from one signal box to the first stop signal (that is to say, the home signal) controlled by the next signal box. The section signal OFF aspect is the authority to enter the block section. Page 18 of 21
Intermediate block home signal A stop signal that controls the exit from an intermediate block section. Intermediate block section The line between the section signal and the intermediate block home signal controlled from one signal box in the same direction of travel. The section signal OFF aspect is the authority to enter the block section. Intermediate token instrument A mid-section token instrument, usually located at a ground frame with a shutting-in facility (see GK/RT0077) and used by authorised railway personnel to facilitate token exchange. Material change Any change to an asset or the use of an asset that has the potential to affect physical or operational interfaces. Movement authority The authority given by a signaller, issued via the signalling system to the driver, which is the authority to move the train within defined limits. No signaller token block section A section of single line directly controlled from one signal box and extending in each direction of travel from the section signal or equivalent lineside operational sign at one end, to the home signal or equivalent lineside operational sign at the other end of the section. The electric token is the prime authority to enter the block section. No signaller token block remote section A section of single line which is supervised but not directly controlled from a signal box and extending in each direction of travel from the stop board, lineside operational sign or buffer stop at one end to the stop board, lineside operational sign or stop block at the other end of the section. The electric token is the prime authority to enter the block section. No signaller token instrument A token instrument located at the remote end of a no signaller token block section and used by authorised railway personnel to facilitate token exchange. One-train staff instrument / controller / receptacle A type of single line instrument which comprises a designated container for the safe storage of one-train staff at a signal box or token control point. The one-train staff controller is an active instrument that can detect the presence of the one-train staff and control its extraction. The one-train staff receptacle is a passive instrument. One-train staff or token A physical object which may be issued to the driver to provide the authority to enter a single line. One-train working A method of signalling on a single line, with or without a one-train staff, where only one train at a time is permitted on an out-and-back basis. Opposing locking Locking applied to a signal route by a route set in an opposing direction. Overlap The distance that must be clear beyond a stop signal (and, where necessary, locked) before the preceding stop signal can display an OFF aspect. Page 19 of 21
Radio electronic token block (RETB) section A designated section of running line between and including token exchange points, operated under the radio electronic token block (RETB) system of signalling. Reduced overlap An overlap that is shorter than a full overlap, where the minimum permitted approach speed is below a specified level which still allows an unrestricted approach to a stop signal displaying the stop aspect. Restricted overlap An overlap that is shorter than a full overlap, which is available only when the preceding signal is subject to approach control by selection of a warning class route. Section signal A stop signal controlling the entrance to a block section or intermediate block section. Signal box The building in which the signaller(s) is situated, together with the signalling control and indication system. This includes any manned block post. Single line A bi-directional line which is the only line that carries running movements between two locations. Single line instrument An instrument which can contain one or more tokens or a one-train staff and controls their release. Station limits The term station limits is used to describe a section of line between two adjacent block sections that is under the control of one signal box or token control point. Station limits extends on each signalled line from the first home signal to the section signal. Token control point A location other than a signal box where a token or one-train staff may be obtained, returned or exchanged. Token exchange The process of transferring a single line token or one-train staff between the signaller or single line instrument and the driver. Token exchange point A passing loop, station area, siding or portion of line on a railway signalled using the radio electronic token block (RETB) system where trains are permitted to receive, return or exchange electronic tokens. Tokenless block section A section of single line extending, in each direction of travel, between the last stop signal (that is to say, the section signal) controlled from one signal box to the first stop signal (that is to say, the home signal) controlled by the next signal box. The section signal OFF aspect is the authority to enter the block section. Track circuit block A method of signalling trains in a section of line using track circuits or other means of automatic train absence detection and without using block instruments. The signal OFF aspect is the authority to enter the signal section. Train completeness Confirmation that the train is complete after it has arrived at the end of a block section. Page 20 of 21
References The Catalogue of s gives the current issue number and status of documents published by. This information is also available from www.rgsonline.co.uk. Documents referenced in the text RGSC 01 s Code RGSC 02 Standards Manual s GE/RT8000 GE/RT8075 GE/RT8270 GI/RT7033 GK/RT0044 GK/RT0045 GK/RT0077 GK/RT0192 documents GK/GN0655 Rule Book AWS and TPWS Interface Requirements Assessment of Compatibility of Rolling Stock and Infrastructure Lineside Operational Safety Signs Permissive Working Lineside Signals, Indicators and Layout of Signals Ground Frames and Shunters Releases Level Crossing Interface Requirements Guidance on Page 21 of 21