T Hr Sc 02000 St

T HR SC 02000 ST

Standard

Mandatory Requirements for Signalling Safeworking Procedures

Version 3.0

02000 ST v4.0, 04/05/2021 Issued date: 30 September 2016

Important Warning

This document is one of a set of standards developed solely and specifically for use on Transport Assets (as defined in the Asset Standards Authority Charter). It is not suitable for any other purpose.

You must not use or adapt it or rely upon it in any way unless you are authorised in writing to do so by a relevant NSW Government agency. If this document forms part of a contract with, or is a condition of approval by a NSW Government agency, use of the document is subject to the terms of the contract or approval.

This document is uncontrolled when printed or downloaded. Users should exercise their own skill and care in the use of the document.

This document may not be current. Current standards may be accessed from the Asset Standards Authority website at www.asa.transport.nsw.gov.au.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Standard governance

Owner: Lead Signals and Control Systems Engineer, Asset Standards Authority Authoriser: Chief Engineer, Asset Standards Authority Approver: Executive Director, Asset Standards Authority on behalf of the ASA Configuration Control Board

Document history

Version Summary of changes 1.0 First issue. 2.0 Minor technical changes to the following topics: • treatment of trainstop failures in Section 12.2.2 • provision of trainstop suppression during re-railing in Section 17.3 • testing of points open-switch position in Section 24 • testing of points open-switch detection in Section 24.5 • requirements for removal of lock slides and provision of wide cut notch point lock in Section 24.6.2 • correction of dc relay types for track circuit minimum shunt resistance in Table 2 • testing of earth leakage detectors following trip-reset in Section 28.5

02000 ST v4.0, 04/05/2021 • insulation testing of track circuit cables and wires in Section 28.6.2 and 28.7.2 Relocated requirements for momentary bridging to Section 15.2 Document formatting changes.

For queries regarding this document, please email the ASA at [email protected] or visit www.asa.transport.nsw.gov.au

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Version Summary of changes 3.0 • Updated Section 11 in relation to signalling irregularities: o excluded the incident of one broken level crossing road boom from the category of signalling irregularity, subject to conditions (LX remains activated) o excluded a signal displaying no lights from the category of signalling irregularity o improved the definition of signalling irregularities (wrong side vs not wrong side) o clarified the example of level crossing protection failures that are deemed wrong side o clarified the example of a level crossing protection failures that are deemed not wrong side o clarified the definition and examples of effective elements of a safe condition o removed reference to 'phantom signal indication' from the example of effective elements of a safe condition to make the example relevant to all irregular signal indications • Updated Section 12 in relation to the protection of signalling failures: o included the requirement to obtain details of failure from signaller and to inform signaller of intended actions o clarified the requirement to provide protection for signalling failures (for signalling irregularity, the protecting signals may be booked back into use after the investigation has identified the cause and subsequently been rectified or addressed) o updated the treatment of signal failures displaying no lights at all (requirement to restrict the higher indications of the signal in rear if delays to rectify failure are incurred) o clarified the note pertaining to less restrictive signal indications and irregular signal indications (to be treated as a signalling irregularity) o clarified the temporary bridging requirement of a trainstop that has failed in the lowered position o clarified the requirement to protect signalling for trainstop failures 02000 ST v4.0, 04/05/2021 o updated the requirement to protect signalling for point failures • Updated Section 13.2 in relation to the intermediate level of securing signalling out of use o permitted the temporary disconnection of signal lights and level crossing protection equipment, and disarrangement of trackside apparatus such as points, releasing switches and ground frames for the purpose of signalling maintenance o clarified the requirement of signalling personnel remaining in attendance during the application of the intermediate method of securing signalling out of use • Updated Section 13.4.1 to clarify the requirement for disconnection of trainstops • Updated Section 13.4.2 in relation to disconnection of points, to clarify the typical situations where the points are disarranged

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Version Summary of changes 3.0 (cont'd) • Updated Sections 16.2.2 & 16.2.3 in relation to elaborate on causes of unreliable track circuits • Updated Section 19.4 in relation to like for like renewals: o removed the mandatory requirement for the use of the actual scope and authorisation form and work instructions contained in SPG 0711, and allow the operator/maintainer to produce forms that convey the same intent and contain the same key elements o clarified the requirement of work instructions where used for multiple equipment o clarified the intent of work instruction such to initial completion of tasks progressively throughout the work • Updated Section 21.3.3 in relation to Q type BRB 930 relays, to include inspection for evidence of overheating • Updated Section 21.3.5 in relation to Q type BRB 930 relays, to ensure adequate inspection coverage is achieved • Updated Section 22.1 to clarify the requirement for active and passive level crossing signals and signs • Updated Section 24.2 to include the requirement to check point lock and detection components as part of prerequisite tasks • Updated Sections 24.3.1, 24.4.2, 24.4.3 & 24.5.4 in relation to clarifying the requirements for HLM style detectors • Updated Section 24.5 in relation to the open-switch detection specification, to align the specification with adjustments available in existing point mechanisms • Updated Section 24.5.2 in relation to operating bar detection, to clarify the specification arrangements. Removed the ASA methodology allowing operator/maintainer RIM to state own methods in signalling safeworking procedures to comply with specified requirements

02000 ST v4.0, 04/05/2021 • Updated Table 2 and Table 3 to include new values for ET 200 track circuits • Updated Section 25.3.7 to include inspection of traction bonding for areas not associated with track circuits • Updated Section 26 to clarify the requirements for passive level crossings • Updated Section 27.1 in relation to testing interlockings, to clarify the authority levels for interlocking testers • Updated Section 28.6.2 in relation to periodic insulation testing of cable conductors, to clarify the requirements for conducting core to core test of spare cores in external main cables • Updated Section 28.7.1 in relation to insulation testing exemptions, to consolidate the exemptions applicable to computer based interlockings thus show them generically rather than type-specific (Sections 28.7.2 & 28.7.3 deleted) • Updated Section 29 in relation to specific requirements of computer based interlockings, to consolidate the requirements thus show them generically rather than type specific and include requirements introduced by Smartlock systems

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Preface

The Asset Standards Authority (ASA) is an independent unit within Transport for NSW (TfNSW) and is the network design and standards authority for defined NSW transport assets.

The ASA is responsible for developing engineering governance frameworks to support industry delivery in the assurance of design, safety, integrity, construction, and commissioning of transport assets for the whole asset life cycle. In order to achieve this, the ASA effectively discharges obligations as the authority for various technical, process, and planning matters across the asset life cycle.

The ASA collaborates with industry using stakeholder engagement activities to assist in achieving its mission. These activities help align the ASA to broader government expectations of making it clearer, simpler, and more attractive to do business within the NSW transport industry, allowing the supply chain to deliver safe, efficient, and competent transport services.

The ASA develops, maintains, controls, and publishes a suite of standards and other documentation for transport assets of TfNSW. Further, the ASA ensures that these standards are performance-based to create opportunities for innovation and improve access to a broader competitive supply chain.

The Mandatory Requirements for Signalling Safeworking Procedures standard has been

02000 ST v4.0, 04/05/2021 developed by the ASA from TMG J000 Signalling Safeworking Procedures (known as Manual J). It specifies the principles of signalling safeworking and the minimum mandatory requirements for operator/maintainer signalling safeworking procedures.

This document has been revised to provide clarity of content and consolidation of requirements to accommodate emerging technologies and changes in the signalling environment.

This document has been approved by the ASA Configuration Control Board (CCB) and is a third issue.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Table of contents

Table of contents ...... 6 1. Introduction ...... 10 2. Purpose ...... 10 2.1. Scope ...... 10 2.2. Application ...... 10 3. Reference documents ...... 10 4. Terms and definitions ...... 11 5. Network rules and procedures ...... 13 6. Principles of signalling safeworking ...... 13 7. Authority to work on the operational signalling system ...... 14 7.1. Signalling permit to work ...... 15 8. Authority to operate signalling controls ...... 16 9. Testing equipment, tools and radio transmitter devices...... 16 9.1. Calibration requirements ...... 17 9.2. Radio transmitter devices ...... 18 10. Derailments and collisions ...... 19 10.1. Licensed signalling personnel attendance ...... 19 10.2. Signal engineer attendance ...... 19 02000 ST v4.0, 04/05/2021 11. Signalling irregularities and wrong side failures ...... 20 11.1. Examples of signalling irregularities that are deemed- wrong side failures ...... 20 11.2. Examples of signalling irregularities that are deemed not wrong side failures ...... 21 11.3. Examples of effective elements of a safe condition ...... 22 11.4. Treatment of signalling irregularities ...... 22 11.5. Investigating signalling irregularities ...... 23 11.6. Signalling irregularity certification requirements ...... 24 11.7. Signalling irregularity reporting requirements ...... 25 12. Signalling failures (fail safe) ...... 25 12.1. Analysis of signalling failures ...... 26 12.2. Protection of signalling failures ...... 26 12.3. Temporary repairs ...... 31 13. Securing signalling apparatus out of use ...... 32 13.1. Disconnection from interlocking ...... 33 13.2. Requirements for securing signalling apparatus out of use ...... 33 13.3. Infrastructure booking authority ...... 35 13.4. Signalling disconnection requirements ...... 35 14. Temporary bridging of signalling circuits ...... 39 14.1. Booking protecting signals into use ...... 40 14.2. Approval for temporary bridging ...... 41

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

14.3. Jumper wires for temporary bridging ...... 42 14.4. Testing of temporary bridging ...... 43 14.5. Temporary bridging left unattended ...... 43 14.6. Reinstatement advice for temporary bridging ...... 43 14.7. Non-vital signalling circuits ...... 44 15. Release of track and indication locking ...... 44 15.1. Rules and types of releases ...... 44 15.2. Momentary bridging ...... 46 15.3. Requesting a release ...... 46 15.4. Precautions before releasing normal indication locks on signal levers ...... 47 15.5. Precautions before releasing normal/reverse locks on point or facing point lock levers ...... 47 15.6. Precautions before releasing normal/reverse indication locks on point levers ...... 47 15.7. Precautions before releasing point lock relays at standard relay interlockings ...... 48 15.8. Precautions before releasing signal normal indication relays at standard interlockings ...... 49 15.9. Precautions before releasing approach stick relays ...... 49 15.10. Precautions before releasing signal route normal relays at route control interlockings ...... 49 15.11. Process for releasing route holding in point lock relay circuits at route control interlockings ...... 50 15.12. Providing releases for other situations including computer based interlocking ...... 51 16. Management of seldom used signalling apparatus ...... 51 16.1. Point configurations at risk ...... 52 16.2. Track circuits at risk ...... 54 02000 ST v4.0, 04/05/2021 17. Requirements for re-railing and associated trackwork ...... 57 17.1. Licensed signalling personnel attendance ...... 58 17.2. Infrastructure booking authority requirements ...... 59 17.3. Protection of rail traffic ...... 59 17.4. Traction return arrangements ...... 60 17.5. Requirements for newly installed rails ...... 61 17.6. Reinstatement of signalling...... 62 17.7. Control and issue of temporary rail bonds ...... 63 18. Requirements for providing adequate traction return ...... 64 18.1. Exemption to providing alternative traction arrangements ...... 65 18.2. Work affecting negative return at substations or section huts ...... 65 18.3. Work affecting impedance bonds ...... 66 18.4. Temporary rail connections for overhead wiring...... 66 19. Minor signalling additions, alterations and renewals work ...... 66 19.1. Risk mitigation requirements for minor additions, alterations or renewals ...... 67 19.2. Involvement of signal engineer for risk mitigation requirements ...... 68 19.3. Work not affecting the design principle ...... 69 19.4. Like for like renewal work ...... 70 19.5. Work affecting the design principle ...... 74 19.6. Rewiring and wire repair requirements ...... 74 19.7. Documents used for the certification of signalling ...... 76

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

19.8. Paralleling of contacts in trackside apparatus ...... 76 20. Requirements and scheduling of signalling maintenance ...... 77 20.1. Maintaining operational signalling equipment ...... 77 20.2. Safety related examinations ...... 78 20.3. Maintenance scheduling, reporting and recording ...... 80 21. Inspection and testing of vital signalling relays ...... 81 21.1. Precautions and requirements for vital signalling relays ...... 81 21.2. Storage and reuse of vital signalling relays ...... 82 21.3. Maintenance and overhaul of vital signalling relays ...... 83 22. Inspection and testing of signals and signs ...... 87 22.1. Requirements for periodic and responsive signal sighting ...... 87 22.2. Maintenance and inspection of signals ...... 88 23. Gauging of trainstops ...... 92 24. Inspection and testing of points ...... 93 24.1. Objective of point testing ...... 94 24.2. Prerequisite tasks for point testing ...... 94 24.3. Requirements for point lock testing mechanically operated points ...... 95 24.4. Requirements for point lock testing power operated points ...... 96 24.5. Requirements for point detection testing ...... 97 24.6. Provision for lock slide removal and wide cut notch point lock ...... 101

02000 ST v4.0, 04/05/2021 24.7. Provision to extend point detection limits ...... 103 25. Inspection and testing of track circuits ...... 103 25.1. Objective of track circuit inspection, testing and maintenance ...... 104 25.2. Track circuit records ...... 105 25.3. Track circuit inspection and tests ...... 105 25.4. Track circuit precautions ...... 111 25.5. Safety critical and safety significant track circuit tasks ...... 114 26. Inspection and testing of level crossing protection ...... 116 26.1. Maintenance and inspection of level crossing protection equipment ...... 117 26.2. Treating reports of level crossing failure ...... 119 27. Inspection and testing of signalling interlockings ...... 119 27.1. Authority to test signalling interlockings ...... 120 27.2. Testing altered locking on interlocking frames greater than eight levers ...... 121 27.3. Interlocking test certificates ...... 121 27.4. Periodic testing of mechanical interlockings ...... 121 27.5. Periodic testing of relay interlockings ...... 122 27.6. Periodic testing of computer based interlockings ...... 123 28. Inspection and testing of electrical insulation ...... 123 28.1. Detecting earth leakage ...... 125 28.2. Minimum acceptable values ...... 125 28.3. Determination for further testing ...... 125

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

28.4. Analysis and test records ...... 126 28.5. Inspection and testing of power supply busbars...... 126 28.6. Inspection and testing of electrical conductor insulation ...... 127 28.7. Circuits exempt from periodic insulation testing ...... 132 29. Specific requirements for computer based interlocking systems ...... 134 29.1. Security of interlocking data ...... 134 29.2. Handling and storage of interlocking modules and equipment...... 135 29.3. Interlocking system time setting ...... 135 29.4. Interlocking system site records ...... 135 29.5. Interfering with operational computer based interlocking equipment ...... 136 29.6. Authority to upload or program interlocking data ...... 139 29.7. Tools and test equipment used on computer based interlocking systems ...... 140 30. Surveillance inspections ...... 142 30.1. Scope of surveillance inspections ...... 142 30.2. Scheduling of periodic inspections ...... 143 30.3. Surveillance inspection reports and action requirements ...... 143 31. Housekeeping and protection of signalling assets ...... 144 31.1. Prevention of water ingress to signalling equipment ...... 145 31.2. Prevention of fire around signalling equipment ...... 145 32. Control of signalling documentation ...... 145 32.1. Requirements for signalling documentation control ...... 146 02000 ST v4.0, 04/05/2021 33. Control of signalling security locks and keys ...... 147 33.1. Lock types in use ...... 148 33.2. Major signal boxes and control centres ...... 149 33.3. Configuration and key cutting ...... 150 34. Storage and dispatch of operational safeworking keys ...... 151 34.1. Temporary storage of operational safeworking keys ...... 151 34.2. Dispatching operational safeworking keys for repair, replacement or cancellation ...... 152

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

1. Introduction

Signalling safeworking procedures are owned and operated by the operator/maintainer in accordance with their obligations to the rail regulator as rail infrastructure managers.

This standard sets out the minimum mandatory requirements to be included in the operator/maintainer signalling safeworking procedures.

Additionally this standard specifies the authority levels required of signalling personnel when working on the operational or potentially operational signalling system.

It forms the basis for the operator/maintainer to develop the procedures for signalling safeworking relevant to their domain rail environment.

2. Purpose

The purpose of this document is to provide a coherent regime of work practices that aim to ensure the continued safety and reliability of the operational signalling system. It also aims to safely bring into use new or altered signalling systems, equipment and wiring within the heavy rail network, as governed by TfNSW.

2.1. Scope 02000 ST v4.0, 04/05/2021 This standard covers information on signalling safeworking which can affect the safe operation and reliability of the signalling system and all its components, including the effect on rail traffic and users at level crossings, when worked on by signalling personnel.

This standard does not include matters relating to work health and safety or worksite protection.

2.2. Application

This standard applies to the signalling systems within the heavy rail network, as governed by TfNSW.

3. Reference documents

The following documents are cited in the text. For dated references, only the cited edition applies. For undated references, the latest edition of the referenced document applies.

Australian standards

AS 4292.1 Railway Safety Management Part 1: General Requirements

AS 4292.4 Railway Safety Management Part 4: Signalling and Telecommunications Systems and Equipment

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Transport for NSW standards

ESG 100 Signal Design Principles

ESG 007 Glossary of Signalling Terms

SPG 0711 Inspection and Testing of Signalling

Train Operating Conditions (TOC) Manual

Other reference documents

Operator Network Rules and Network Procedures

4. Terms and definitions

The terms defined in ESG 007 Glossary of Signalling Terms and the following definitions apply in this standard and shall be incorporated in signalling safeworking procedures:

AEO Authorised Engineering Organisation; a legal entity (which may include a Transport Agency as applicable) to whom the ASA has issued an ASA Authorisation

ASA Asset Standards Authority

ASA Authorisation an authorisation issued by the ASA to a legal entity (which may include a Transport Agency as applicable) which verifies that it has the relevant systems in place to carry

02000 ST v4.0, 04/05/2021 out the class of asset life cycle work specified in the authorisation, subject to any conditions of the authorisation. The issue of ASA Authorisation confers the status of ‘Authorised Engineering Organisation’ or ‘AEO’ on the entity.

ATP automatic train protection

authorised signalling personnel signalling personnel who are not licensed, but have been assessed and authorised to perform specific unsupervised work within a signalling environment in accordance with ASA's signalling competency standard and the operator/maintainer’s competency management system, the AEO's competency management system; and hold suitable competency for the intended task

CBI computer based interlocking

certification of signalling apparatus documentary evidence provided for the purpose of booking specific signalling apparatus into operational use, following satisfactory testing in accordance with the relevant requirements, by signalling personnel

EMR master emergency facility

EOL emergency operation lock

EPROM erasable programmable read-only memory

EEPROM electrically erasable programmable read-only memory

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

ESML emergency switch machine lock

interlocking an electrical, electronic or mechanical means of making the operation of one piece of apparatus dependent upon certain predetermined conditions being fulfilled by other apparatus. The logic by which routes that conflict are prevented from being set at the same time.

licensed signalling personnel signalling personnel who hold a valid licence for either signal engineer, signal electrical or signal mechanical, attained in accordance with ASA's signalling competency standard and the operator/maintainer’s competency management system; and hold suitable competency for the intended task

like for like renewal the renewal, or temporary removal and subsequent reinstatement of signalling equipment that may be performed without a signalling design authority

operator/maintainer the entity accredited by the rail regulator, to act as rail infrastructure manager for the operation and maintenance of railway infrastructure

responsible signal engineer a licensed signal engineer (field) who acts in the interest of the operator/maintainer for the continuous integrity of signalling infrastructure within an assigned area of accountability (for example, a maintenance signal engineer or asset signal engineer)

signalling commissioner (also known as commissioning engineer) a licensed signal engineer (field) who acts in the interest of TfNSW and the relevant rail infrastructure managers, to bring

02000 ST v4.0, 04/05/2021 into use new or altered, safe and reliable, signalling systems in accordance with the specific signalling design and ASA requirements

signal engineer a signalling person who is licensed to the level of signal engineer (field)

signalling irregularity a failure of a signalling unit or its subsystem which is contrary to the intended design requirement; is not fail-safe and which in combination with other failures or circumstances may bring the system to an unsafe condition. Additionally, the definition of a signalling irregularity is extended to items of signalling that are found with errors, where these errors have the potential to falsely energise a vital relay or other vital function.

signalling permit to work a documented authority issued to signalling personnel by the AEO acting on behalf of the operator/maintainer to enable work within an operating signalling environment or signalling commissioning environment

signalling personnel (for the purpose of signalling safeworking) the persons who are either licensed signalling personnel or authorised signalling personnel

signalling safeworking procedures the operator/maintainer’s document for their domain signalling safeworking procedures

SPAD signal passed at danger (stop)

TfNSW Transport for New South Wales

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

5. Network rules and procedures

Signalling safeworking procedures shall complement the applicable network rules and network procedures and shall not supersede them.

Signalling safeworking procedures shall reference the applicable network rule/procedure as pertinent to the related paragraph.

Signalling personnel shall comply with the requirements stated in both network rules and network procedures, and signalling safeworking procedures.

6. Principles of signalling safeworking

Signalling safeworking procedures shall incorporate the following principles of signalling safeworking:

• Signalling work shall be managed and performed to meet the relevant requirements of AS 4292 Part 1 General Requirements and Part 4 Signalling and Telecommunications Systems and Equipment.

• The movement of trains shall be protected in the following circumstances:

o when signalling equipment has failed in an unsafe manner or becomes unreliable

02000 ST v4.0, 04/05/2021 o when any signalling work or other work impairs or can impair the protection afforded by the signalling system

• Signalling irregularities shall be promptly attended and thoroughly investigated. The defect shall be rectified or addressed, and the equipment tested and certified as operating safely before being restored for operational use.

• Signalling failures shall be recorded and analysed to determine trends and the necessary corrective actions required to provide a safe and reliable signalling system.

• Where the interlocking is disarranged or vital signalling equipment is disconnected from the interlocking or is disarranged, renewed or has safety critical adjustments altered, the safe operation of the interlocking shall be certified fit before restoring it back into use.

• Risks associated with the signalling apparatus that are seldom used shall be managed and controlled to minimise the level of risk. Human factors shall be considered when mitigating such risks.

• Alterations or additions to the signalling system or changes to its configuration shall not be made unless properly approved by the designated person within the contracted AEO that provides the design assurance accountability. This includes alterations or additions to signalling trackside equipment, train control systems, automatic train protection (ATP) equipment, vital communication links and power supplies. Alterations or additions shall

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

comply with SPG 0711 Inspection and Testing of Signalling and signalling safeworking procedures.

• New or experimental equipment intended for use on the signalling system shall meet the ASA requirements for type approval before being installed in operational areas.

• Like for like renewal determinations and performed work shall be in accordance with the operator/maintainer's like for like work instructions and signalling safeworking procedures.

• The protection defeated by contacts of vital signalling apparatus temporarily bridged shall be provided by an effective alternative means.

• Temporary repairs of vital signalling equipment shall be done to a safe and secure standard. Any temporary repair made shall be brought up to a permanent standard before the temporary work presents an unacceptable risk.

• Sound asset management methods shall be applied to ensure the signalling system and its components are maintained to provide the inherent safety and reliability aspects of the signalling system throughout its operational life.

• Signalling equipment shall be suitably secured to minimise risks associated with unauthorised access and vandalism.

• Signalling plans, track insulation plans, circuit books, control tables, diagrams, interlocking

02000 ST v4.0, 04/05/2021 data and the like shall be maintained up to date and be available to those who need them in order to carry out their duties.

• Testing equipment, tools and items used to maintain the signalling system shall be in proper working order and comply with ASA requirements, as applicable. Testing and measuring equipment used for certifying the safety and reliability parameters of the signalling system shall be suitably calibrated.

• Where line pole routes are still in use, they shall be maintained by persons holding appropriate competency to do the work. However, licensed signalling personnel shall retain accountability for the signalling elements of the work.

• Off-site repair and overhaul of vital signalling equipment shall be controlled in order to ensure the equipment is restored to the relevant specification and standard before being re-used.

7. Authority to work on the operational signalling system

Only licensed signalling personnel shall work on the operational signalling system and its associated equipment and wiring. They shall perform signalling work only as prescribed on their certificate of competency and signalling permit to work.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Persons who are not licensed in signalling shall not interfere with the operational signalling system, including its equipment and wiring. They shall not perform any task that can affect the adjustment of operational signalling equipment. An exception is permitted in the following situations:

• when persons are specifically instructed by licensed signalling personnel

• when persons are supervised directly and closely by a licensed signalling person who shall take responsibility for the work being performed by the non-licensed person

Authorised signalling personnel are permitted to perform specific unsupervised work within a live signalling environment. They shall perform work only as prescribed on their certificate of competency and signalling permit to work. Such work may include the supervision of non-signalling personnel during specific non-invasive tasks such as installation work, cabling, wiring, mechanical and civil works as prescribed on the signalling permit to work.

Authorised signalling personnel may also perform or lead testing and certification of signalling apparatus in accordance with their certificate of competency and signalling permit to work. The affected signalling shall be first booked out of use and disconnected from the interlocking by a licensed signalling person before the testing work can proceed.

7.1. Signalling permit to work

02000 ST v4.0, 04/05/2021 The signalling permit to work is a documented authority granted by the operator/maintainer to signalling personnel for work that can affect the safety and reliability of operational signalling. The process aligns with other signalling requirements such as interface coordination meetings and site integrity agreements.

Additionally, the signalling permit to work is a process which establishes each signalling person's capability to perform the tasks intended for the work. The signalling personnel's work shall be limited to their licence/authority level and competency, taking into account their experience and the site specific circumstance and conditions.

The signalling permit to work shall only pertain to the operator/maintainer's network.

A signalling permit to work shall be required before work can proceed within an operating signalling location or on operational signalling equipment, which includes the following:

• signalling interlocking equipment

• vital and non-vital signalling systems and links

• train control systems

• signalling trackside equipment

• signalling power supplies

• communication equipment used for signalling

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• signalling air systems

• signalling mechanical equipment

• signalling cables, wires, routes and pits

A signalling permit to work shall also be required before work can proceed on new (green-field) signalling installations that involve inspection, testing and certification of the operational interface during the commissioning phase of a project.

The signalling permit to work shall be issued to signalling personnel by the AEO acting on behalf of the operator/maintainer. The AEO acting on behalf of the operator/maintainer may also grant overall permission to another contracted AEO to administer the permit to work arrangements on their behalf for the duration of permitted work.

The actual granting of signalling permits to signalling personnel shall be done by a signal engineer holding accountability.

8. Authority to operate signalling controls

The operation of controls by signalling personnel for the purpose of testing signalling apparatus shall be done only in the following conditions:

• with the signaller’s consent 02000 ST v4.0, 04/05/2021 • only where the operation has no potential to endanger the movement of trains or other rail vehicles or users at level crossings

• only when the affected signalling has been booked out of use

Signalling personnel shall attain an understanding of the controls that are permitted to be operated by them, the extent of the test area and the agreed time frame for the testing.

Signalling personnel shall not operate signalling controls for operational purposes.

Where devices such as releasing switches or token keys are provided for ground operated signalling, and the work does not disconnect or disarrange the equipment from the interlocking, there is no requirement to book out the equipment before its operation for testing purposes; however the signaller's permission shall still be obtained.

9. Testing equipment, tools and radio transmitter devices

Only testing equipment that complies with ASA requirements shall be connected to signalling circuits and equipment.

This requirement applies to portable monitoring, chart recording and logging devices when directly connected to working circuits and equipment. When these devices are used, the

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

installation of their associated wiring shall be in accordance with temporary repair requirements stated in Section 12.3 of this standard.

Temporary repair requirements that pertain to the connection of testing equipment may be exempt in situations where the persons remain in attendance. Disconnections of wiring in this case shall be avoided. However, any disconnections made shall be suitably tested.

Under no circumstances shall the feed/transmitter and the relay/receiver of the same track circuit be fed into the same recording or logging device, even if the recorder or logger channels are isolated. This requirement avoids the risk of the track circuit train detection being electrically bypassed by the recorder or logger.

Test probes used for testing live signalling circuits shall be appropriately insulated and suitable for attaching to the terminals required for test.

Test lamps or test LEDs shall not be used as they can provide a significant leakage path for circuit currents.

Tools used for specific purposes, such as crimping tools, shall be suitable for the task and shall comply with ASA requirements, as applicable.

9.1. Calibration requirements

Testing and measuring equipment used to certify the safety and reliability parameters of the 02000 ST v4.0, 04/05/2021 signalling system shall require on-going calibration.

The following are examples of testing and measuring equipment that require on-going calibration:

• multimeters

• inductive type ammeters (clamp, tong meters)

• insulation resistance testers (meggers)

• track circuit frequency adaptors and selective frequency meters

• track shunt boxes

• lightning arrestor testers

• point and trainstop gauges

• measuring wheels

Specific tools, when used on safety critical work, shall require on-going calibration.

The following are examples of specific tools that require on-going calibration:

• lug crimping tools

• torque wrenches

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

All calibrations shall be in accordance with manufacturer's specification unless other relevant specifications apply.

9.2. Radio transmitter devices

Radio transmitter devices emit electro-magnetic energy that can interfere with electronic signalling and testing equipment.

The following are examples of radio transmitter devices that emit electro-magnetic energy:

• handheld two-way radios such as Government Radio Network (GRN) and Citizen Band (CB) radio

• mobile phones

• cordless phones

• Wi-Fi enabled devices

• ATP programming and testing equipment

To minimise the likelihood of interference, these devices shall not be used close to electronic vital and non-vital signalling equipment or when using some testing equipment.

The following are examples of electronic signalling equipment and testing equipment that can be affected by radio transmitter devices: 02000 ST v4.0, 04/05/2021

• computer based interlocking equipment

• audio frequency track circuits

• electronic power supplies and electronic changeover units

• clamp and tong meters

• digital multimeters

When testing equipment is affected by radio interference, error readings can display on devices such as clamp meters, tong meters and digital multimeters. When these devices are affected by radio interference, any measurements taken shall not be used for the purpose of certification.

Most radio transmitter devices shall not be used within three metres of affected signalling and testing equipment. Calls from mobile or cordless phones shall not be made or answered within three metres of affected signalling or testing equipment; however, the phone may be used up to one metre of affected signalling or testing equipment, once the call is established. Wi-Fi enabled devices and ATP programming and testing equipment shall not be used within one metre of affected signalling and testing equipment.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

10. Derailments and collisions

Derailments and collisions shall be promptly attended in order to provide appropriate protection for trains by booking out of use the protecting signalling, including signalling on adjacent or obstructed lines. Signalling shall be protected in accordance with signalling safeworking procedures, and network rules and network procedures. Signalling suspected of contributing to the cause of the incident shall be booked out of use, but not disconnected. In these cases, the protecting signals in the rear of the incident shall be booked out of use and disconnected.

Any derailment or collision where the signalling is thought to be the cause shall be treated as a signalling irregularity and a signal engineer shall attend to the incident.

For incidents involving emergency services or otherwise where the incident has the potential to become a crime scene, signalling personnel when attending the incident shall consider aspects of interference, independence and access for emergency services. In these cases, signalling personnel shall coordinate their actions in conjunction with the relevant authorities and senior rail management.

10.1. Licensed signalling personnel attendance

Licensed signalling personnel shall attend to all derailments or collisions, unless the affected lines where the incident occurred have no signalling provided (for example, non-signalled

02000 ST v4.0, 04/05/2021 yards). They shall ensure appropriate signalling protection, gather information and evidence and perform other tasks as instructed by the investigating signal engineer. Care shall be taken not to disturb any evidence.

The position of levers/controls, indications, signals, points, relays and other trackside apparatus that are applicable to the circumstances shall be noted.

10.2. Signal engineer attendance

When signal engineers are required to attend a derailment or collision, they shall perform the following functions:

• ensure signalling safeworking protection arrangements are appropriate

• gather evidence and investigate the incident where signalling is suspected to be the cause

• provide safe alternative signal engineering arrangements to facilitate train running as necessary

• facilitate incident recovery and restoration works

• lead testing and certification requirements, including the provision of an inspection and test plan

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• compile a detailed report

• make recommendations to prevent recurrence of this incident

11. Signalling irregularities and wrong side failures

All signalling irregularities shall be immediately attended to, protected and investigated in accordance with signalling safeworking procedures.

Note: Not all signalling irregularities result in immediate failure. Some can remain in the system as latent defects or errors to the intended design requirement, which can later emerge, adversely affecting the safe running of trains.

Predictable, common failure modes such as a lamp and LED unit failures on a signal or level crossing, or a trainstop that is falsely in the lowered position due to a mechanical problem are not deemed signalling irregularities. Additionally, a single broken road boom at a level crossing is not deemed a signalling irregularity, on condition that the level crossing remains in an activated state.

Signalling irregularities vary in the level of danger they present to trains and people. This is essentially dependent on the level of protection that is inherently available during the prevailing conditions. Such protection can be afforded by the system's design or the presence of effective elements of a safe condition. These safe provisions potentially reduce the risk caused by the

02000 ST v4.0, 04/05/2021 failure and as such, this type of signalling irregularity is deemed 'not wrong side'. Refer Section 11.2 for examples of signalling irregularities that are deemed not wrong side failures. Refer Section 11.3 for examples of effective elements of a safe condition.

A wrong side failure is neither protected by the system design, nor has sufficient effective elements of a safe condition for the particular circumstance; this can directly endanger the safe running of trains or people. Refer Section 11.1 for examples of signalling irregularities that are deemed wrong side.

11.1. Examples of signalling irregularities that are deemed wrong side failures

Following are examples of signalling irregularities that are deemed wrong side failures:

• point locking: if points are released under conditions when they should be locked

• point detection: if point detection is made when the points are not in their correct position

• facing points: if a signal can be cleared over facing points when the points are not locked or correctly detected

• signal indication: if a less restrictive indication is displayed by a signal than is correct for the conditions allowed

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• rail vehicle detection: if a track circuit or axle counter fails to detect the presence of a rail vehicle

• level crossing protection: if level crossing protection equipment fails to operate for approaching trains and the protecting signals are not automatically replaced or held at stop in order to protect the failure

Note: This example does not pertain to a level crossing having an insignificant amount of lights out, one broken boom, or one failed bell or siren, or when the level crossing is in manual operation.

• interlocking: if a release can be incorrectly obtained from the locked position

• vital signalling relay: if a vital signalling relay is falsely energised due to internal or external interference or defect, which subsequently causes a reduction in system safety

• electric lock: if an electric lock is incorrectly free

• dual control: if the restoration of any one control fails to return the signal to the stop

11.2. Examples of signalling irregularities that are deemed not wrong side failures

Following are examples of signalling irregularities that are deemed not wrong side failures: 02000 ST v4.0, 04/05/2021 • signal indication: if a signal displays an irregular combination of lights that is obviously seen as an invalid indication

• level crossing protection: if level crossing protection equipment fails to operate for approaching trains and the system design causes the protecting signals to be replaced or held at stop in order to protect the failure

Note: This example does not pertain to the level crossing having an insignificant amount of lights out, one broken boom, or one failed bell or siren, or when the level crossing is in manual operation.

• level crossing pedestrian gate: if only one pedestrian gate remains partially open due to a mechanical problem – conditional that the remaining elements of the level crossing have activated correctly and it is evident that trains are approaching

Refer Section 11.3 for examples of effective elements of a safe condition.

• vital signalling relay: if a vital signalling relay is falsely energised due to internal or external interference or defect, and the system design provides proving of the relay's de-energised position (back contact proving) and thus protecting the system

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

11.3. Examples of effective elements of a safe condition

In some cases of signalling irregularity, where it is clearly evident that the system has failed, there can still remain sufficient effective elements to provide a safe condition.

These safe elements can alert people such as signallers, drivers, and users at level crossings of the prevailing conditions.

Examples of effective elements of a safe condition include the following:

• a pedestrian gate not closing when required

The possible effective elements can include the following:

o the obvious activation of the level crossing protection

o the detection of the gate not closing (XNR) and protecting signal held at stop

• a signal indication which has an irregular combination of lights that is obviously seen as an invalid indication

The possible effective elements can include the following:

o the driver recognising the irregular signal indication

o the signal in rear correctly indicated the proceed-authority for the signal ahead (for example, caution if the failed signal was at stop) 02000 ST v4.0, 04/05/2021

11.4. Treatment of signalling irregularities

All reports of signalling irregularity shall be treated as factual and promptly attended to.

Signalling equipment suspected of causing an irregularity shall be protected by arranging protecting signals to stop.

The suspected signalling equipment shall only be booked out of use and not initially disturbed or disconnected, unless instructed by the investigating signal engineer.

The immediate failed signal may be disconnected in conjunction with being booked out of use, if it is clearly evident that the cause of irregularity is not within the signal operating circuit or its controlling relay/module.

Where a failed signal is not disconnected (booked out of use only), the protecting signals in the rear of the failed signal shall be booked out of use and disconnected.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The protecting signals in the rear may be restored in the intervening period until the signalling irregularity is rectified on the following conditions:

• the actual cause of the signalling irregularity is positively determined by the investigating signal engineer

• rail traffic can safely operate using the signals in accordance with network rules and network procedures

• the failed signal is disconnected in conjunction with being booked out of use

• the immediate protecting signal is deemed sufficient protection for the signalling irregularity

The immediate protecting signal shall remain booked out until the defect is rectified or addressed.

11.4.1. Signalling data logs

Data logs from vital and non-vital signalling systems, used for the purpose of providing information and evidence following a serious incident (such as signalling irregularity, derailment, collision and so on) shall be reviewed by a signal engineer first before being passed on to other parties.

Data logging systems include computer based interlockings, train control systems, vital and non-vital data recorders, and level crossing monitors. Productions from replay facilities, asset 02000 ST v4.0, 04/05/2021 monitoring facilities, as well as video and still footage are also included in this requirement.

The log information provided shall be an unaltered download, separately interpreted and attested. The information shall be a true representation of the actual event, supported by accurate commentary to describe the event in plain language. The logger time shall be checked against real time to determine the difference.

The critical inputs and outputs used in logger events, supplied as evidence for serious or major incidents shall be verified to be correct in accordance with the design requirements.

11.5. Investigating signalling irregularities

All signalling irregularities shall be investigated by a signal engineer.

A suitable independent person is required to witness the investigation, except for simple cases. Refer Section 11.5.1 for simple cases.

In case of serious consequences or implications, the investigation shall be conducted by a senior, experienced signal engineer, independent of the pertaining circumstances.

The investigating signal engineer is responsible to determine the signalling system is safe to restore for normal operational use. The investigating signal engineer shall be satisfied that upon completion, the investigation has been properly and thoroughly conducted.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Where the cause of signalling irregularity is not immediately known, the investigating signal engineer shall compile an inspection and test plan as part of the investigation strategy to determine the causal factors.

Where the testing has the potential to impair the safety provided by the signalling system, or otherwise interferes with train operations, the signalling affected by the testing shall be booked out of use.

11.5.1. Simple cases of signalling irregularity

The term simple case refers to a signalling irregularity which includes the following:

• an incident which is not a collision, derailment or near miss

• there is no injury or damage

• there are no extraordinary circumstances pertaining

• there remained sufficient effective elements of a safe condition

• the cause found is non-contentious and obvious to the signalling personnel attending

In simple cases of signalling irregularity, the investigating signal engineer is not required to attend on site in order to conduct the investigation. However, the investigating signal engineer is still the person responsible to determine if the signalling system is safe to restore and shall be

02000 ST v4.0, 04/05/2021 satisfied that the identified cause satisfactorily explains the situation.

11.6. Signalling irregularity certification requirements

Certification of the signalling system shall be made only when the investigation has concluded, and upon any of the following conditions:

• a genuine cause has been found or determined and the affected apparatus has been rectified or otherwise addressed

• the alleged report is proven to be unsubstantiated by thorough testing which has verified the signalling to be working safely and in accordance with the signalling design

The investigating signal engineer shall refer the incident to another signal engineer who holds accountability, for instruction in any of the following cases:

• a significant incident occurs (main-line or passenger occupied train derailment, collision or near miss) and the signalling system is suspected to be at fault

• a recurrence of the irregularity cannot be ruled out, which can potentially result in serious consequences

• the alleged report or confirmed irregularity cannot be satisfactorily explained and the investigating signal engineer has deemed the apparatus to remain booked out of use

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Note: The signal engineers involved need to have suitable experience relative to the complexity of the subject matter.

11.7. Signalling irregularity reporting requirements

A comprehensive report shall be compiled by the investigating signal engineer for all incidents of signalling irregularity. The report shall contain the events and details of the incident, details of the technical investigation conducted, test results and applicable evidence such as logs, photos, statements, and so on. The report shall also include rectification measures, either completed or proposed, including further investigations if appropriate, and any recommendations.

12. Signalling failures (fail safe)

All signalling functional failures shall be attended and subsequently reported, recorded and analysed so that trends can be identified and appropriate measures be taken to reduce failures to a minimum. A failure management system shall be used for this purpose.

Repairable items with unique serial numbers that have failed, such as vital signalling relays, track transmitters/receivers, CBI equipment and the like, shall be identified in the failure management system so that the performance can be tracked once they are returned to service.

Signalling conditional failures which do not have an impact on functional failures or rail

02000 ST v4.0, 04/05/2021 operations need not be recorded in the failure management system, but shall be prioritised and managed using a defect management system.

During a failure, the best possible arrangements shall be made in accordance with signalling safeworking procedures, and network rules and network procedures. This is done in order to maximise the safe use of the signalling system and minimise train delays, while still retaining an appropriate level of protection for trains. Human factors leading to error shall be considered when determining the course of action to be taken in this regard.

Licensed signalling personnel shall obtain details from the signaller about the circumstances of the failure and any symptoms or indications that can assist in providing diagnoses of the cause. Licensed signalling personnel shall advise the signaller of any intended actions that can disrupt the operation of trains; for example, the requirement to disable or book out of use any signalling, or testing that can interfere with signal indications.

Under no circumstances shall signalling personnel cause a signal to display a less restrictive indication. A signal shall not be made to clear by means of manipulation, interference, bridging of contacts or by other similar actions except as specifically laid down in signalling safeworking procedures.

When temporary repairs are made to correct a failure condition the responsible signal engineer shall be advised and the temporary repair treated in accordance with Section 12.3.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

12.1. Analysis of signalling failures

The signal engineer responsible for handling signalling failures shall regularly analyse signalling failure data and make recommendations as applicable.

The following list describes the analysis for the different types of signalling failures:

• Repeat and no cause found failures shall be thoroughly investigated and if required, escalated to a higher level for investigation to determine appropriate courses of action in preventing recurrence. A file shall be retained for these failures.

• Failures caused by vandalism shall be analysed to determine appropriate measures of security in an attempt to minimise recurrence of these types of failures.

• Rail lines or signalling apparatus seldom used shall be analysed to minimise failures associated with seldom use, including assessment and mitigation of associated risks.

• Failures caused by persons performing work shall be analysed to ensure the interference caused by workers is addressed to prevent recurrence and thus not impair the safety and reliability of the signalling system caused by these failures.

• Failures caused by signalling component defects shall be analysed to determine appropriate measures to minimise recurrence of these failures. This analysis shall include identification of equipment used at other locations that can be impacted by similar failure

02000 ST v4.0, 04/05/2021 modes.

12.2. Protection of signalling failures

In the event of a signalling failure, it may not always be necessary to book out and disconnect signalling apparatus. The risks associated with removal of the normal operation of signals, points and so on shall be assessed and considered in order to maximise the safe use of the signalling system.

However, signalling shall be made to provide protection in any of the following situations:

• signalling irregularity, until the investigation has determined the cause and the defect subsequently rectified or addressed

• the safety of the signalling can be impaired by an intervening action (for example, signalling equipment is disarranged or disconnected from the interlocking)

• the signalling equipment is unreliable and can result in signals inadvertently returning to stop on approaching trains

• the failure condition remains unrectified and routes become unavailable for a considerable amount of time

• if requested by the network operator

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

12.2.1. Failure of signals

The loss of signal indications whether caused by a defective lamp or LED unit, or caused by other electrical or mechanical defect shall be promptly rectified.

Where colour light signals have failed such that they display no lights at all, these shall be treated as a high priority. Where delays to rectify such defect are incurred, the higher indications of the signal in rear shall be restricted to indicate the most restrictive proceed-aspect for the running signal (for example, 'caution' or 'low-speed').

Note: Signals displaying a less restrictive indication or an indication containing an irregular combination of lights that is obviously seen as an invalid indication (for example, top green with top red over lower red), is deemed a signalling irregularity and treated in accordance with Section 11 of this standard.

Refer Section 22 of this standard for other procedures associated with signals and signs.

12.2.2. Failure of trainstops

A trainstop that falsely indicates a raised position, or due to an irregular circuit operation (and not a mechanical problem) is falsely in the lowered position, shall be deemed a signalling irregularity. These instances shall be treated in accordance with Section 11 of this standard.

Where a trainstop has failed such that it no longer provides protection, an attempt to enable the 02000 ST v4.0, 04/05/2021 trainstop to the raised position shall be made. Where a trainstop cannot be enabled in the raised position, the associated signal shall be booked out of use and a fixed mechanical trainstop fitted in place. If a fixed mechanical trainstop is not available, then the signal in the rear of the failed trainstop shall also be booked out of use. In this case, the failed trainstop may have its Normal contacts temporarily bridged. A temporary bridging authority shall be issued for this purpose. The jumper wires shall be installed inside the trainstop. Temporary bridges shall be removed before the signal is booked back into use.

Note: Trainstops fitted with VCSR functionality may be left in the lowered position without the need for temporary bridging and the signals may be left operational.

Where a trainstop has failed to operate to the lowered position, the trainstop shall not be manipulated to the lowered position. However, where it is necessary to allow trains to progress past the affected signal, an exemption to this requirement is permissible only on meeting all of the following conditions:

• the signal associated with the failed trainstop is not protecting points

• a VCSR function is in operation on the failed trainstop

• the failure is independent of the signal controls failing

• the integrity of the trainstop Normal contacts and their circuits are not compromised or in doubt

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

In these cases, there is no need to apply temporary bridging and the signal may be left operational.

Signals, affected by trainstops that have failed in the raised position, may be left operational provided a proceed-aspect is available from the signal when the trainstop is in the raised position (as provided by the intended circuit design); for example, a low speed or shunt indication.

Notwithstanding the above requirements, protecting signals associated with a failed trainstop shall be booked out of use during any of the following situations:

• when the trainstop is removed

• when cabling to the trainstop is disconnected

• when the trainstop detection wiring is interfered with

Signallers shall be advised of the operational impacts caused by failed trainstops.

Trainstop suppression during signalling system failures

Events such as signalling system failures, train control system failures, power supply failures and so on can affect signals and retain the trainstops in the raised position. In such cases, network operators may choose to institute manual block working in accordance with network rules and network procedures. Subsequently, network operators can request that affected 02000 ST v4.0, 04/05/2021 trainstops be suppressed to facilitate this operation.

In these situations trainstops may be suppressed, subject to a licensed signal engineer assessing and mitigating the risks that apply in each situation.

The associated signal shall be booked out of use before a trainstop is suppressed.

The signal engineer shall determine whether to apply temporary bridging or not. If temporary bridging is required, a temporary bridging authority to bridge-out the trainstop Normal contacts shall be issued. The jumper wires shall be installed inside the trainstop. The temporary bridges shall be removed before the signal is booked back into use.

Trainstops at entry block posts shall not be suppressed.

12.2.3. Failure of points

When points have failed, no attempt shall be made to unlock or move the points other than from the signalling control unless the affected points and protecting signals have been booked out of use.

Emergency switch machine locks (ESML) and emergency operation locks (EOL) are facilities which are interlocked with the signalling. Licensed signalling personnel may use ESML and EOL as permitted by the signaller to manually operate points for the purpose of diagnosing and rectifying a failure. This may be done without booking the affected points and signals out of use.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Where electro-pneumatic points are not fitted with emergency facilities, the point control unit's internal actuator arrangements may be utilised for this purpose.

In all cases, the signaller shall be notified first to place the affected signals to stop. Licensed signalling personnel shall be assured that there are no approaching trains before the emergency facilities are used. Upon reinstatement of the emergency facility, the position of the points shall be left in correspondence with the signalling control and interlocking.

Where the point lock mechanism has failed such that it does not effectively lock the points, the affected points and protecting signals shall be booked out of use. The affected points and protecting signals shall also be booked out of use when the point detection is not in correct adjustment or is unreliable (for example, causing signals to inadvertently return to stop on approaching trains). Facing points shall be clipped and SL locked.

Protecting signals may be left operational on failed points only where the following conditions are met:

• the points are not disarranged or disconnected from the interlocking

• the point lock (if applicable) remains in correct adjustment and is secure

• the point detection remains in correct adjustment and working order

• the point switches remain secured in correct position

02000 ST v4.0, 04/05/2021 • the detector indications on the signaller's diagram correctly show the points in their set position

• any impending work will not cause the points to become disarranged or disconnected from the interlocking

In this case, the points need not be clipped and locked provided licensed signalling personnel remain in attendance. The prevention of point creep, which can cause loss of detection and potential unlocking of points, shall be considered.

Where the failure is a result of damaged or defective electrical point detection components, which can cause severe train disruption, a temporary bridging authority to bridge-out the failed detector contacts, may be issued.

12.2.4. Failure of ESML or EOL detection

Where there is a failure of detection or there is a missing point handle or key pertaining to an ESML or EOL cabinet which results in severe disruption to trains, a temporary bridging authority to bridge-out the detector contacts of the ESML or EOL may be issued. The ESML or EOL cabinet including the manual operation facility at the points shall be secured using signalling Falcon 8 locks.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The points' manual operation facility shall be booked out of use; however the points and signals may be left operational using the signalling controls.

12.2.5. Failure of plunger locks or isolating relays

A failed plunger lock on electro-pneumatic points or an isolating relay on electric points may be momentarily released as requested by the signaller to enable the points to be operated from the signalling control. A separate request shall me made by the signaller for each release.

If the plunger lock or isolating relay is not effectively locking the points, the points shall be deemed defective and the affected points and protecting signals shall be booked out of use. Facing points shall be clipped and SL locked.

12.2.6. Failure of track circuits

In the event of a track circuit failure, no attempt shall be made to clear affected signals by manipulating the track circuit relay or by bridging across the track circuit relay contacts or terminals.

A release of track or indication locking affected by a failed track circuit may be provided but only as prescribed in signalling safeworking procedures. Refer Section 15 of this standard for requirements associated with the release of track and indication locking.

02000 ST v4.0, 04/05/2021 Where a track circuit does not provide an effective track shunt, the protecting signals and any associated points shall be booked out of use. This is done until adequate measures are implemented to address the risks associated with the loss of effective track shunt. Facing points shall be clipped and SL locked. The responsible signal engineer shall be advised of the situation and shall subsequently implement adequate measures.

Where a track circuit failure is caused by a broken rail the immediate protecting signals shall be made to remain at stop. Alterative traction return arrangements shall be provided.

Signals shall be made operational on the following conditions:

• certification of the affected rail by a competent person

• satisfactory testing of the track circuit following remedial work

12.2.7. Failure of level crossing protection equipment

Failures of level crossing protection equipment shall be protected in accordance with network rules and network procedures.

Signals interlocked with failed level crossings shall also be booked out of use whenever the level crossing is booked out of use.

Level crossings fitted with master emergency facilities or other approved level crossing manual override arrangements shall not be disconnected, provided they are in correct working order.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The level crossing battery supply shall be checked to ensure that it has sufficient charge following periods of prolonged power supply loss.

12.2.8. Failure of electric locks on signal levers

When the Normal electric lever lock fails on a signal lever, the lever shall be kept in the normal position until the failure has been rectified. The associated signal shall be observed to display a stop indication.

12.2.9. Failure of interlocking relays

At standard relay interlockings, relays such as signal reverse relays, point normal/reverse relays and releasing switch normal/reverse relays shall not be lifted or falsely energised or released.

At route control interlockings, relays such as route reverse lock relays, point normal/reverse lock relays and releasing switch normal/reverse lock relays shall not be lifted, or falsely energised or released.

There is an exception in the case of route holding in point lock relays as stated in Section 15.11 of this standard.

12.2.10. Failure of section control relays in single line track control sections 02000 ST v4.0, 04/05/2021 In the event of failure of a section control relay in track controlled areas with pilot working, it may be permissible to temporarily bridge-out the half pilot staff contacts. This can be done at one or both ends of the section for testing purposes provided the starting signals at both ends of the section are booked out of use. A temporary bridging authority shall be issued for this purpose.

12.2.11. Failure or damage to signalling cables and wires

When failures are caused by broken or damaged signalling cables and wires, no attempt shall be made to manipulate any relay or equipment affected by the defect. The affected signalling shall be booked out of use until the items are effectively repaired.

The work of repairing or replacing signalling cables and wires shall be done in accordance with Section 19.6 of this standard.

12.3. Temporary repairs

Temporary repairs shall be done only where the work does not affect the design principle. The work shall be done in accordance with Section 19 of this standard, which outlines the specific requirements for additions, alterations and renewals work, and the level of authority required to undertake such work. The requirement also outlines the associated risks and lists examples for mitigation.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The testing of temporary repairs shall comply with the requirements prescribed in SPG 0711.

The responsible signal engineer shall be notified of all temporary repairs made. A temporary repairs register shall be kept updated by the responsible signal engineer as a record for this purpose. The register shall include any risk mitigation requirements and the prioritisation of permanent repairs.

All items utilised for temporary repairs, including wires, cable cores, contacts and other components, shall be suitable for the intended purpose.

Temporary wiring shall be suitably tagged, identifying the particular circuit and associated terminal number.

Under no circumstances shall exposed or bare wire ends be left loose or have the potential to come into contact with live circuits.

Signalling documentation shall indicate the nature of the temporary repair. Additionally, signalling documentation as certified by a competent signal engineer shall be duly sent for updating as necessary to reflect any permanently changed arrangements.

13. Securing signalling apparatus out of use

Signalling apparatus is secured in a safe, de-energised or locked state during degraded modes in order to prevent its operation. 02000 ST v4.0, 04/05/2021 Situations where the signalling integrity has been impaired or can become impaired shall be adequately protected by securing the signalling apparatus out of use.

Maximising the safe use of the signalling system shall be considered when determining the course of action for securing the apparatus out of use. This may permit some of the signalling apparatus to remain operational.

This consideration shall be subject to a risk assessment conducted by a signal engineer and the implementation of an appropriate mitigation to bring any identified risk to an acceptable level. The potential for human error shall be given due consideration during the risk assessment.

For example, where points are affected by rail contamination, the route control functionality may be retained while still disabling the protecting signals from clearing. This enables all the points in a route to operate as designed and eliminates the human error associated with manually operating points. This can prevent a points run-through.

The mitigation strategy shall be discussed between the signal engineer and another signal engineer before implementing, to ensure all risks are controlled.

Note: The signal engineers involved need to have suitable experience relative to the complexity of the subject matter.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Engineering works performed in track possessions shall meet the same requirements for securing signalling apparatus out of use, as if the work was being performed on running lines.

13.1. Disconnection from interlocking

Signalling is deemed disconnected from the interlocking when the disconnection affects the integrity provided by the interlocking for the safety of train movements.

The opening of circuit terminal links and pins or the disconnection of electrical power or air supply to trackside apparatus alone does not constitute disconnection from the interlocking.

There is an exception in the case of signal lights and level crossing protection equipment where it shall be deemed disconnected from the interlocking if their indication or operation is disabled.

13.2. Requirements for securing signalling apparatus out of use

The requirement to book signalling apparatus out of use each time may not always be necessary. The methodology used to prevent the operation of signalling shall be relative to the level of protection required.

Signalling safeworking procedures shall prescribe the methods based on the following protection requirements as a minimum: 02000 ST v4.0, 04/05/2021 • Signallers can apply blocking facilities to secure signalling controls in a specified position (generally normal). This method does not provide a high level of protection as the signalling remains potentially operable. It is suitable only for the immediate protection of a derailment, collision or failed train or otherwise for the protection of engineering works where the work does not affect the signalling system.

• Licensed signalling personnel can disable signalling apparatus to prevent its operation by removing electrical power or air supply to motors, mechanisms or control devices. This method provides an intermediate level of protection because the disabled trackside apparatus (for example, points, releasing devices) is still safely connected to the interlocking. Therefore, the apparatus may not require booking out of use and the signals may remain operable.

This method applies where the trackside apparatus is not disarranged and is safely connected to the interlocking; additionally, where the work does not interfere with the safe operation of the signalling system and does not impact the on-time running of trains.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

An example of engineering works that can suit this type of protection is as follows:

o inspection and testing of signalling equipment to rectify a failure

o inspection and testing of signalling equipment to certify its correct operation during periodic or reactive testing

o periodic maintenance of signalling equipment When performing signalling maintenance, some work can involve the disconnection of signal lights or level crossing protection equipment (making the equipment inoperable), or the disarrangement of points or other trackside apparatus such as releasing switches and ground frames. Such work is permitted using this method only where the disconnection or disarrangement occurs for a very short period of time (less than the time between trains, but not greater than 30 minutes).

This permission is strictly for signalling maintenance of the following tasks:

i) temporary disconnection of signal lights for the purpose of periodic insulation testing

ii) momentary disabling of active level crossing protection equipment using designated switches, such as emergency and manual override switches, for the purpose of periodic testing and maintenance

02000 ST v4.0, 04/05/2021 iii) minor adjustment of point locks, point detection or individual elements of other trackside apparatus, such as releasing switches and ground frames, for the purpose of periodic testing and maintenance

In these maintenance situations, the protecting signals in the rear of the affected apparatus shall be disabled, such that they remain at stop for the duration of the work. The disabling of signals in the rear may be exempt where the responsible signal engineer has assessed all the risks and determined that the reduction in signalling safety caused by the work will not endanger the safe running of trains or users at level crossings.

Signallers shall be advised of all work that secures signalling using this method and shall be requested to apply blocking facilities to relevant signalling controls. Licensed signalling personnel shall remain in attendance throughout the time this method is applied.

• The most secure method of protection is afforded when licensed signalling personnel book out of use the trackside apparatus.

This shall be done in any of the following situations:

o where disabled signalling equipment requires the use of hand signallers to facilitate the movement of rail traffic, or the movement of users at level crossings

o where signalling apparatus requires disconnection from the interlocking

o where signalling apparatus is disarranged

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

o where the safe operation of the signalling is put at risk by engineering works

o where the integrity of the signalling is in doubt In these cases, the following approach shall be adopted:

o an understanding with the signaller is achieved of the work involved, the implications to rail operation, and the safeworking requirements to be applied

o compiling an infrastructure booking authority in accordance with network rules and network procedures

o requesting the signaller to place blocking facilities on specific signalling controls

o protecting signals made to remain at stop by electrical or mechanical disconnection

o disabling the operation of the trackside apparatus concerned and securing the equipment in a safe state (for example, clip and SL lock points)

o disabling and securing in a safe state, other equipment that interlocks with the trackside apparatus concerned

13.3. Infrastructure booking authority

Licensed signalling personnel are responsible for compiling the infrastructure booking authority whenever they are involved in the booking out of signalling apparatus. The physical 02000 ST v4.0, 04/05/2021 disconnection of signalling apparatus shall begin only after obtaining the signallers approval.

The infrastructure booking authority may be transcribed by the parties where the worksite is remotely located from signallers or train controllers.

Signing the infrastructure booking authority when restoring signalling apparatus into use shall constitute certification that the affected interlocking and signalling apparatus has been tested to be safe and fit to restore for normal operational use.

Signalling apparatus booked out of use for a period greater than six months shall be formally advertised in a weekly notice (or similar) in addition to compiling the infrastructure booking authority.

13.4. Signalling disconnection requirements

Signalling disconnections when left unattended shall be clearly labelled and made secure to prevent the possibility of wrongful reconnection.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

When disabling signalling, the isolation shall be confined to any of the following:

• removing fuses and disconnecting pins

• unplugging of coded plug couplers and the like

• turning OFF circuit breakers, isolating switches or air cocks

In general the removal of wires from terminals or relays, or the removal of mechanical equipment should not be warranted. However, where this is absolutely necessary, the reinstatement shall be suitably tested.

The disconnection of relays and devices shall preferably occur within the same location as the relay/device; otherwise two points of disconnection (one on each leg of the relay/device circuit) is required.

13.4.1. Disconnection of signals

Any trainstop associated with a signal made inoperable, shall also be made inoperable to prevent its inadvertent operation.

Signals made inoperable shall continue to display a stop indication consistent with the design requirements; otherwise the protecting signals in the rear shall be booked out of use. Additionally, signals that are manipulated to display a proceed-indication for the purpose of testing shall also have protecting signals in the rear booked out of use. 02000 ST v4.0, 04/05/2021

The removal of power to signal lights shall constitute disconnection from the interlocking.

The following disconnection requirements pertain to situations where the signalling integrity is not in doubt or where the integrity is not affected by the work. Where the signalling integrity is in doubt or affected by the work, a more stringent means of disconnection and protection shall be considered (for example, disabling the higher indications of the protecting signals and the affected signals in the rear and other signals affected by the work).

Disconnection of signals activated by control relays

Signals shall be made to remain at stop by electrically disconnecting the control relay for the first proceed-aspect (typically the HR/caution relay, low speed relay, or shunt control relay).

Where signals provide more than one route, it is permissible to disable only the affected routes while still maintaining the functional routes to operate. Route links, where these are provided, shall be used for this purpose.

Disconnection of signals activated by computer based interlockings

Signals shall be made to remain at stop by inhibiting the signal operating output using technician controls at a maintainer’s interface, or by electrically isolating the circuits that prevent the signal from clearing.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Disconnection of signals activated by mechanical interlocking (large levers)

Signals shall be made to remain at stop by removing the respective signal lever catch rod pivot pin and slackening off the signal wire. Distant signals shall be made to remain at caution accordingly.

13.4.2. Disconnection of points

Points are disconnected for the purpose of either disabling their operation or booking out of use.

Where points are disarranged, the points shall be booked out of use and the protecting signals booked out of use. Protecting signals may be left operational when the points are not disarranged.

Following are some typical situations where the points are disarranged:

• point lock is not effective and secure

• point detection is not in proper adjustment

• point switches are not held in their correct position or in proper condition

• critical mechanical connections are not effective and secure

• if points can be incorrectly released 02000 ST v4.0, 04/05/2021 Points that are booked out of use shall also be clipped and SL locked. Where points are not disarranged and the requirement is only to disable their operation, then it may not be necessary to clip and lock the points unless required by network operators or other factors.

Points that are disabled or booked out of use for an extended period can be affected by unreliable track circuits (which do not provide an effective track shunt) and the requirements of seldom used signalling apparatus, in accordance with Section 16 of this standard shall apply.

When booking points out of use, the unavailability of emergency facilities for point manual operation (EOL or ESML) shall be considered if the infrastructure (track, signalling, and overhead wiring) is not fit for use. In such cases, the facility shall be locked with a Falcon 8 lock and the information of the unavailability of the infrastructure shall be stated on the infrastructure booking authority.

The following disconnection requirements pertain to the different point operating types:

Disconnection of points operated mechanically

The operation of mechanical points shall be disconnected by removing the catch rod pivot pin for the respective point lever and facing point lock lever, as applicable.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Disconnection of points operated electrically

The operation of electrical points shall be disconnected by electrically isolating all ends of the set of points concerned. On some machines, the points can require power-operation upon restoration to ensure the mechanism has operated to its full stroke.

If motors are turned OFF for an extended period, then the prevention of point creep shall be considered.

Disconnection of points operated pneumatically

The operation of pneumatic points shall be disconnected by electrically isolating all ends of the set of points concerned. Additionally, the pneumatic supply to each point end shall be isolated except where it is necessary to maintain an air-on situation to prevent point creep.

When isolating the pneumatic supply, maintaining the detection of air pressure switches in some point control units shall be considered.

13.4.3. Disconnection of level crossings

Level crossing protection equipment not fitted with master emergency arrangements (EMR) or other approved level crossing manual override arrangements shall be disconnected by electrically isolating the level crossing control relay or output. Where Up Road and Down Road

02000 ST v4.0, 04/05/2021 control relays are provided, the relevant relay shall be electrically isolated (depending upon the affected approach tracks). In single line areas where Up Direction Stick and Down Direction Stick relays are provided, both relays shall be electrically isolated. The operation of road and pedestrian boom and gate mechanisms shall be electrically isolated (by means other than operating the boom emergency switches) and the road booms tied in the raised position. Pedestrian booms and gates shall not be tied in the raised/open position. Additionally, protecting signals that interlock with the level crossing shall be booked out of use.

Level crossings that are fitted with EMR or other approved level crossing manual override arrangements enable full functionality of the level crossing protection equipment during manual operation irrespective of the status of the control circuits. This maximises the availability of warning provided by the level crossing. Master emergency switch operation (or override function) deactivates the level crossing operation in the raised position and causes the signals on the approach side of the level crossing (where provided) to display stop. When it becomes necessary to allow rail traffic to pass, the manual operating switch (or similar in override arrangements) is used to activate the level crossing protection. The signals shall clear once the level crossing has been proved in the lowered position and the availability of other conditions.

Level crossings fitted with EMR or other approved level crossing manual override arrangements, when booked out of use, need not be disconnected unless the level crossing protection equipment itself is inoperable.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The removal of power to level crossing protection equipment shall constitute disconnection from the interlocking.

13.4.4. Disconnection of track circuits

Track circuits shall be disconnected to prevent the energisation of the parent track circuit relay/output. Care shall be taken to ensure track circuit relays/outputs are not falsely energised by other track circuits or power sources.

The transmitter/feed end and receiver/relay end shall be electrically isolated from the respective trackside apparatus. Additionally, 50 Hz ac, dc and high voltage impulse (HVI) tracks circuits such as Jeumont Schneider type shall have their transformer/battery/transmitter power supply isolated. For audio frequency overlay track circuits such as PSO 4000, the power supply to transmitters and receivers shall be retained where practical. This will avoid loss of the volatile memory that contains the date and time logs. Disconnection of audio frequency overlay track circuits shall be done by isolating the transmitter and receiver links in the location.

Note: Where the power supply is removed from audio frequency overlay track circuit transmitters or receivers, this will necessitate the resetting of the time and date function.

For Microtrax coded track circuits, the power supply to master and slave cardfiles shall be retained where practical. Disconnection of Microtrax coded track circuits shall be done by 02000 ST v4.0, 04/05/2021 isolating the links within the track interface panel at both ends of the track.

13.4.5. Disconnection of releasing switches and electric lever locks

Releasing switches and electric lever locks shall be disconnected to prevent their operation by electrically isolating the coil operating circuit. A test shall be conducted to ensure that the device is inoperative.

14. Temporary bridging of signalling circuits

The principle for using temporary bridging states that the protection defeated by the bridging is provided by an effective alternative means.

Temporary bridging of signalling circuits shall be done only in exceptional circumstances as necessary to minimise disruption to trains caused by signalling equipment that is damaged or is disconnected or disarranged.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Temporary bridging shall not be connected across any contacts which provide protection for the movement of trains in either of the following cases:

• where it prevents signalling apparatus from properly returning to a more restrictive position or locked position

• where it allows unprotected signalling apparatus to operate to a less restrictive or unlocked position when it is not safe to do so

Temporary bridging of signalling circuits shall be performed in accordance with signalling safeworking procedures.

Signalling apparatus with temporary bridging applied shall be booked out of use. Safe arrangements shall be made to secure the apparatus concerned so that it cannot be moved out of correspondence with the interlocking and the bridged-out position. Signals affected by the apparatus temporarily bridged shall also be booked out of use except where stated in Section 14.1.

Temporary bridging shall be confined to bridging of closed contacts of trackside signalling apparatus that indicate the locked, fail-safe position of the apparatus. For example, the Normal indicating contacts of signals at stop or trainstops in the raised position or the detection contacts of points in their correct position and locked. The temporary bridging of contacts shall be limited only to failed or removed apparatus. Jumper wires shall be connected as close as possible to

02000 ST v4.0, 04/05/2021 the apparatus concerned.

Contacts that are temporarily bridged shall be disconnected so that the work does not interfere with the live portion of the circuit.

Additionally, where the Normal detector contacts are temporarily bridged; for example, at an end of points, the circuits that provide the Reverse detection shall be disconnected. Similarly, if the Reverse detector contacts are temporarily bridged, the circuits that provide the Normal detection shall be disconnected. This precaution can also apply to other apparatus such as trainstops and level crossing mechanisms.

Only licensed signalling personnel deemed competent to perform the activity of temporary bridging without supervision, shall lead this work.

14.1. Booking protecting signals into use

In order to facilitate train running while temporary bridging is applied, the authorising signal engineer, after due consideration of the associated risks, may permit the booking into use of specific protecting signals.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

This shall be done on the following conditions:

• testing is conducted to ensure correct application of temporary bridging as stated in Section 14.4 of this standard

• point securing equipment such as point-clips, locks and spikes, as applicable, are applied and frequently inspected

Protecting signals shall not be booked into use which would allow trains to operate over lines where signalling equipment is moved out of correspondence with the interlocking and the bridged-out position. Protecting signals shall also not be booked into use where the equipment is disarranged or worked on in a way that the safety of the signalling is impaired (for example, facing points not adequately secured).

The decision to allow protecting signals to operate over disarranged facing points which have been secured by alternative means, shall be discussed between the authorising signal engineer and a signal engineer who holds accountability to ensure all the risks are controlled before implementation.

Note: The signal engineers involved need to have suitable experience relative to the complexity of the subject matter.

14.2. Approval for temporary bridging 02000 ST v4.0, 04/05/2021 Temporary bridging to signalling circuits shall be granted either by an approved circuit design or by a documented process and bridging authority form issued by the authorising signal engineer.

In both cases, the responsible signal engineer shall be notified of the temporary bridging arrangements.

Where temporary bridging is granted by a documented process and bridging authority form, the authorising signal engineer shall discuss the bridging arrangements with the person applying the bridging and with the person removing the bridging. The testing requirements shall also be discussed.

Where it is impractical for the authorising signal engineer to directly issue the bridging authority form, the authorising signal engineer may delegate the issuing of the form to a licensed signalling person who is independent of the work. This person shall transcribe the instructions for the bridging as provided by the authorising signal engineer. The name of the authorising signal engineer shall suffice until a signature is obtained.

Where temporary bridging is granted by an approved circuit design, the work shall be performed in accordance with SPG 0711.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

14.2.1. Approval of temporary bridging by authorising signal engineer

Where temporary bridging is granted by an authorising signal engineer, it shall be performed in accordance with a documented process and a temporary bridging authority form stating at least the following information:

• unique temporary bridging authorisation number

• location and listing of signalling equipment to be bridged

• planned date and time for the application and removal of bridging

• reason for the temporary bridging

• a photocopy, scan or electronic print-out of the diagrams for the circuits bridged

• authorising signal engineer approval (name, signature and date approved)

• the responsible signal engineer advised (name and date advised)

• person nominated to apply bridging (name, signature, time and date bridging applied)

• identification numbers of jumper wires applied

• person nominated to remove bridging (name, signature, time and date bridging removed)

• identification numbers of jumper wires removed 02000 ST v4.0, 04/05/2021 • time and date of removal advice provided to authorising signal engineer

• authorising signal engineer final sign-off (signature and date)

The bridging authorisation number shall be noted on the infrastructure booking authority as stated in network rules and network procedures. Additionally, the word 'BRIDGED' in brackets shall be written alongside each of the equipment listing that has bridging applied.

When booking the affected signalling back into use, signing the infrastructure booking authority shall constitute certification that all the temporary bridging has been removed and the affected signalling has been tested to be safe and reliable.

14.3. Jumper wires for temporary bridging

Jumper wires used for temporary bridging shall be of suitable length and the insulation of bright colour to ensure that the jumper wires are noticeable. The temporary nature of the wiring installation shall be made obvious.

Conductors shall have a minimum cross section of 1.5 mm² with an insulation 0.6/1 kV standard. The connecting lugs, plugs or clips shall be insulated and suitable to its application. The connection shall be secure to ensure that there is no possible connection to an inadvertent terminal or circuit.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Precautions shall be made to ensure jumper wires used for temporary bridging are not interfered with during the time of their application.

Where the authority of temporary bridging is not provided by an approved signalling design, the jumper wires shall be controlled by the authorising signal engineer, individually numbered for identification, registered and stored in a secured box. Issuing of jumper wires shall be limited to the amount required as authorised on the temporary bridging authority form.

Temporary bridging used as part of an approved signalling design shall be in accordance with the relevant design.

In an emergency, the authorising signal engineer may approve the making up of an improvised jumper wire for temporary bridging. The emergency jumper wire shall be fitted with an identification label. The authorising signal engineer shall write down a description of this jumper wire in the temporary bridging authority form. The improvised jumper wire shall be destroyed immediately after the emergency use.

14.4. Testing of temporary bridging

Testing shall be performed to ensure that all contacts not intended for bridging remain effective in the circuit while the temporary bridging is applied. Testing of entire affected circuits shall also be performed upon removal of temporary bridging to ensure all temporary bridges are removed and all contacts are effective in the circuit. This test shall include a correspondence test, an out 02000 ST v4.0, 04/05/2021 of correspondence test (as applicable), a wire/null count and an apparatus function test.

Signals affected by the work shall remain booked out of use until the satisfactory completion of all relevant tests, both upon applying temporary bridges and then upon subsequent removal of temporary bridges.

14.5. Temporary bridging left unattended

Where the temporary bridging is likely to be left unattended for some time, additional precautions shall be made to ensure the jumper wires are not tampered with.

Any facing points clipped shall be XL locked and spiked to prevent an unauthorised movement of the points causing an out of correspondence with the interlocking and the bridged-out position. Any attempt to manually operate the points using an ESML or EOL facility shall be prevented using Falcon 8 locks to secure the equipment.

Precautions of a similar nature shall be applicable to other apparatus temporarily bridged as necessary.

14.6. Reinstatement advice for temporary bridging

The authorising signal engineer shall be notified of the removal of temporary bridging and subsequent testing. These notification arrangements shall be discussed and agreed at the time

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

of authorisation. The authorising signal engineer shall pursue advice of removal if not notified once the agreed notification time has elapsed.

Any required extension of time for the application of temporary bridging shall be approved first by the authorising signal engineer.

14.7. Non-vital signalling circuits

Where non-vital signalling circuits are physically separate from vital signalling circuits, they may be exempt from these temporary bridging requirements.

15. Release of track and indication locking

Release of track and indication locking is provided to manage train movements when the interlocking is locked and unable to become free due to specific situations.

Examples of such situations include the following:

• a failure of an electric lock or circuitry

• an incorrect route set for an approaching train

• a rail vehicle that has failed on a particular section of track

Most track and indication locking is designed to be automatically released by the interlocking; 02000 ST v4.0, 04/05/2021 however there are occasions where licensed signalling personnel are required to provide a manual release when requested by network controllers.

15.1. Rules and types of releases

The interlocking between conflicting signals and/or points and/or level crossings shall not be released.

At standard relay interlockings, relays such as signal reverse relays, points normal/reverse relays and releasing switch normal relays shall not be released.

At route control interlockings, relays such as route reverse relays, point normal/reverse lock relays and releasing switch normal/reverse lock relays shall not be released; however in exceptional circumstances, the route locking in point lock relay circuits may be released.

Manual releases are permitted in accordance with signalling safeworking procedures when either of the following occurs:

• track locking (approach locking and route holding) is locked

• indication locking on mechanical levers (signal normal indication and point normal/reverse indication) is locked

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

At some installations, circuits can combine interlocking with track locking, or track locking with indication locking and it is necessary to ensure that only the specific locking is released.

15.1.1. Locking principles used in interlockings

The following principles of locking relate to the release of interlockings:

Approach locking

Approach locking is provided to prevent the alteration of a route in the face of a train which has received a proceed-signal indication for the route.

This provides an assurance of the following:

• all facing points are in correct position and locked

• trailing points are set for the non-conflicting position (and hence no converging routes can be set)

• opposing signals are retained at stop

Route holding

Route holding is provided to prevent the following for a train that has entered a valid route:

•

02000 ST v4.0, 04/05/2021 the unlocking or movement of facing points within the route

• the alteration of facing points in the overlap to an obstructed overlap

• the alteration of trailing points within the route and in the overlap

• the clearing of opposing signals

Indication locking

Indication locking is provided to ensure all safe conditions are met for train movements before allowing a signal or points lever to enter (or relevant relay to indicate) its full position, which can then free the locking for other signals or points.

15.1.2. Manual releases

Manual releases are only permitted on the following:

• normal indication (NI) electric locks on mechanical signal levers

• normal/reverse (N/R) electric locks on mechanical point and facing point lock levers

• point normal/reverse indication (NI/RI) electric locks on mechanical point levers

• point lock relays at standard relay interlockings

• signal normal indication relays at standard relay interlockings

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• approach stick relays at standard relay interlockings and at route control interlockings

• signal route normal lock relays at route control interlockings

• route holding in point lock relay circuits at route control interlockings

The manual releasing methods shall be limited to the following:

• momentarily lifting an electric lock on mechanical levers while the lever is moved

• momentarily energising a signal normal indication relay at standard relay interlockings, or a point lock relay at standard relay interlockings (not route control interlockings), or a signal route normal lock relay at route control interlockings

• momentarily bridging the track stick contact of the approach stick circuit at standard relay interlockings or at route control interlockings, or the affected track circuit contacts proving the track locking element in a point lock relay circuit at route control interlockings

15.2. Momentary bridging

Momentary bridging is the bridging of specific circuit contacts for the purpose of releasing track locking or indication-locking when performed by licensed signalling personnel. The jumper wire shall be hand held (at least at one end) at all times and never be left connected. The bridge shall be applied momentarily for just sufficient time to allow the release to be given.

02000 ST v4.0, 04/05/2021 The jumper wire and issuing criteria used for momentary bridging are exempt from meeting the temporary bridging requirements; however the jumper wire and connection means used shall be suitable for its application.

15.3. Requesting a release

A formal request for release shall be obtained from the signaller before a manual release is provided. Details of the release shall be entered in a permanent record; for example, an infrastructure booking authority. The details of the release shall be signed by both the signaller and the licensed signalling person.

The signaller shall be requested to place the associated signals to stop and ensure they remain at stop by applying appropriate blocking facilities before a release is provided. Licensed signalling personnel shall also receive an assurance from the signaller (recorded on the request for release document) that all approaching trains have come to a stand and shall remain so.

A separate request shall be obtained for every release given, requiring a separate entry in the permanent record (such as an infrastructure booking authority).

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

15.4. Precautions before releasing normal indication locks on signal levers

Normal indication (NI) locks on signal levers incorporate indication locking and track locking for approach locking and in some cases route holding.

The following precautions shall be observed before providing a release of normal indication locks on signal levers:

• ensure the associated protecting signals are at stop, and the associated trainstops (where provided) are in the raised position

• ensure any train approaching the signal involved has been brought to a stand

• ensure any train occupying track circuits included in the normal indication lock circuit has been brought to a stand and is clear of any points in the route ahead of the signal

15.5. Precautions before releasing normal/reverse locks on point or facing point lock levers

Normal and reverse (N/R) locks on mechanical point or facing point lock levers incorporate track locking generally for both approach locking and route holding.

The following precautions shall be observed before providing a release of normal/reverse locks 02000 ST v4.0, 04/05/2021 on point or facing point lock levers:

• ensure the associated protecting signals are at stop, and the associated trainstops (where provided) are in the raised position

• ensure any approaching train has been brought to a stand

• ensure no train is foul of any of the points worked by the points lever

At hybrid installations containing both mechanical and relay interlocking, ensure that all relay interlocked functions are non-conflicting with the mechanical interlocking. This shall be done before a normal or reverse electric lock is released on a point or facing point lock lever.

Where it is intended to by-pass a train occupying route holding circuits with another train, the licensed signalling person giving the release shall be assured by the signaller that both train drivers are aware of the intended move.

15.6. Precautions before releasing normal/reverse indication locks on point levers

Normal or reverse indication (NI/RI) locks on point levers apply indication locking and do not incorporate track locking.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following precautions shall be observed before providing a release of normal/reverse indication locks on point levers:

• ensure the points are lying in correspondence with the point lever and the point switch blades are in their respective fully closed/fully open positions as applicable, and that facing points where provided are securely locked by the point lock

• ensure the points will not be unlocked or moved before giving the release – if necessary, clip and SL lock the points

Points that remain out of use following an initial release of the indication lock shall not be released again unless the points are booked out of use, clipped and SL locked. The failed indication lock may then be permanently released if necessary. This is done to enable the lever to be placed in correspondence with the points position in order to obtain the sequence of the interlocking.

Rail traffic shall not be permitted to pass over facing points while the point lever is in the NI or RI position unless the points are secured by clip and SL lock.

15.7. Precautions before releasing point lock relays at standard relay interlockings

Point lock relays in standard relay interlockings apply track locking, generally for route holding

02000 ST v4.0, 04/05/2021 and in some cases approach locking.

The release of point lock relays at standard relay interlockings may be provided except in cases of track locking (approach locking). Such approach locking is released by the approach stick relay.

The following precautions shall be observed before providing a release of point lock relays at standard relay interlockings:

• ensure the associated protecting signals are at stop, and the associated trainstops (where provided) are in the raised position

• ensure any approaching train has been brought to a stand

• ensure no train is foul of any points worked by the points control

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

15.8. Precautions before releasing signal normal indication relays at standard interlockings

The release of signal normal indication relays at standard relay interlockings may be provided except in cases of track locking (approach locking); such approach locking shall be released by the approach stick relay.

The following precautions shall be observed before providing a release of signal normal indication relays:

• ensure the associated protecting signals are at stop, and the associated trainstops (where provided) are in the raised position

• electrically disconnect the associated signal to prevent its operation

• ensure any train approaching the signal involved has been brought to a stand

15.9. Precautions before releasing approach stick relays

Approach stick relays are provided for approach locking of signals that protect points.

The following precautions shall be observed before providing a release of approach stick relays:

• ensure the associated protecting signals are at stop, and the associated trainstops (where provided) are in the raised position 02000 ST v4.0, 04/05/2021

• ensure any train approaching the signal involved has been brought to a stand

15.10. Precautions before releasing signal route normal relays at route control interlockings

The release of signal route normal relays at route control interlockings may be provided except in cases of track locking (approach locking); such approach locking shall be released by the approach stick relay.

The following precautions shall be observed before providing a release of signal route normal relays:

• ensure the associated protecting signals are at stop, and the associated trainstops (where provided) are in the raised position

• electrically disconnect the associated signal to prevent its operation

• ensure any train approaching the signal involved has been brought to a stand

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

15.11. Process for releasing route holding in point lock relay circuits at route control interlockings

In route control interlockings, point lock relays incorporate interlocking functions and shall not be released except in the following cases, and only as permitted by a signal engineer:

• a failure occurs of the track locking element in a point lock relay circuit

• the route holding tracks are occupied by a failed rail vehicle

In these cases, the release of track locking shall be performed in accordance with the process for energising the applicable point lock relay. This process allows the point lock relays to be in correspondence with the intended lie of the points. The specific release details shall be fully explained to the signaller.

The following process shall be observed to provide a release of route holding in point lock relay circuits at route control interlockings:

i. instruct the signaller to apply a block to the relevant point control in correspondence with the lie of the points, and to the controls of all signals leading over the points

ii. ensure all signals that interlock with the points are at stop, and the associated trainstops (where provided) are in the raised position

iii. ensure any train that has entered the routes concerned has been bought to a stand 02000 ST v4.0, 04/05/2021 iv. ensure any points or releases which interlock with the points concerned are in non-conflicting positions

v. ensure no train is foul of the points concerned

vi. manually operate the points concerned to the intended (opposite) position and secure by clip and SL lock (this will temporarily place the points out of correspondence with the interlocking)

vii. momentarily bridge the appropriate track locking relay contacts in the relevant point lock relay circuit

viii. instruct the signaller to operate the point control to the centre position, and to observe the points free indication; then (after obtaining the points free indication) to operate the point control to the intended position (normal or reverse) in correspondence with the lie of points

ix. remove the bridge immediately upon the respective point lock relay becoming energised

x. check that the opposite point lock relay is in the de-energised position

No attempt shall be made to operate the point lock relay or points by operating route set buttons.

Contacts in the point lock relay circuit, other than those applying track locking, shall not be bridged.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Point lock relays shall not be manually lifted or replaced with a relay in the energised position.

15.12. Providing releases for other situations including computer based interlocking

Other situations can arise when the signalling interlocking has been locked, causing a need for a release. An example of this is at computer based interlockings, where a loss of track circuit input causes the interlocking to become locked.

In such cases, where the procedures for providing a release are not prescribed by this standard, the risks of providing such a release shall be first identified by a signal engineer.

The decision to release the signalling interlocking shall be decided by the signalling engineer holding accountability for providing assurance.

The principles prescribed in this section shall be applied when permission is granted to provide the release.

16. Management of seldom used signalling 02000 ST v4.0, 04/05/2021 apparatus

Signalling apparatus which is rarely or never used due to a change in rail traffic conditions shall be managed in accordance with signalling safeworking procedures.

A signalling control location (for example, signal box) and its associated apparatus, which are normally closed shall be suitably maintained and tested before certifying the signalling control location back into use.

Signalling personnel shall take every opportunity to inspect the rail surface of track circuits to evaluate the capability of an effective track shunt, particularly at sections of track which are prone to seldom use, such as sidings, refuge lines, crossovers and so on.

Signalling apparatus seldom used that has the potential to impair the safety of the signalling system shall be immediately booked out of use, including the associated protecting signals.

The responsible signal engineer shall be immediately advised of seldom used signalling that pose a risk to the safety of signalling. The responsible signal engineer shall assess and mitigate the risks associated in such situations to an acceptable level and shall retain a register of seldom used apparatus for this purpose. The responsible signal engineer shall liaise with the network operators, with an aim to ensure that sufficient trains are tabled through the track circuits and the affected points that are seldom used to maintain the condition of the rail surface.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The reinstatement of signalling affected by apparatus seldom used shall be conditional upon the signalling (including points) being tested to ensure that they are in working order. The track circuits shall be tested to ensure that they are capable of providing an effective track shunt. Alternatively, where the risks associated in such situations are assessed and mitigated by a signal engineer, the specific signalling may remain operational.

16.1. Point configurations at risk

Following are examples of point configurations which can cause the points to become seldom used:

• emergency crossovers

• power worked double-ended crossovers provided for out of course working

• points at sidings or refuges operated from a remote signalling control location

• points at sidings or refuges locally operated from a ground frame or adjacent control panel

• installed points pending commissioning or removal

Points affected by seldom use for a period greater than nine weeks shall be clipped, XL locked and spiked, unless otherwise governed by specific requirements as stated or referenced in this standard.

02000 ST v4.0, 04/05/2021 Points that are inoperable or have other constraints due to seldom use shall be listed at the relevant signalling control location.

The portion of a turnout that is rarely used forming part of a run-off not governed by a signalled approach may be exempt from 'seldom used' requirements and the points may be left operational.

Where seldom used points become impractical to operate for maintenance purposes and the points are booked out of use, the maintenance may be reduced to the specific tasks stated in Section 16.1.4 of this standard.

16.1.1. Specific requirement for emergency crossovers

Emergency crossovers, whether operated by ground frames released by a releasing switch, duplex lock or similar arrangement, shall be clipped and XL locked in the normal position when the emergency crossover is not in use.

16.1.2. Points at sidings or refuges operated from a ground frame or adjacent control panel

Points at sidings or refuges operated from a ground frame or adjacent control panel may remain operational where the operator can clearly observe the clearance point or other end of points.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

16.1.3. Installed points pending commissioning or removal

Where a set of points is installed pending proper connection to the interlocking or where the interlocking is removed from points pending removal, the point switch blades shall be adequately secured and detected (where necessary) in accordance with ESG 100 Signal Design Principles.

The periodic maintenance of point securing devices for points not properly connected to the interlocking shall be scheduled as if they were operational points. The maintenance tasks shall be performed in accordance with Section 16.1.4 of this standard.

The checking of XL locks, point-clips and point-spikes used to secure installed points that are not connected to the interlocking shall be included in the signal engineer's periodic testing of signalling interlockings in accordance with Section 27.4 of this standard.

16.1.4. Specific maintenance tasks where points are impractical to operate due to seldom use

Where it is impractical to operate points for maintenance purposes due to seldom use, the specific tasks listed below shall be scheduled at the same frequency as operational points. These tasks provide the integrity for the signalled routes that remain operational through the points retained in the normal position.

02000 ST v4.0, 04/05/2021 The specific tasks do not preclude other maintenance activities from being performed on the affected point equipment such as insulation testing or cleaning and lubrication. Full maintenance services shall be resumed before points are made fully operational.

The minimum tasks (as applicable) to be performed for points that become impractical to operate for maintenance purposes due to seldom use include the following:

• check that releasing arrangements and manual operating levers are securely locked

• check for damage to the point equipment including point rods

• check the fastenings are secure and are of the correct type (for example, nyloc nuts)

• check that the point-spikes, point-clips and locks are securely fitted

• ensure the point lock is securely plunged and effectively locking the points

• check the closed-switch is secured against the stock rail throughout its entire length and that the back-drive is not moving or flogging during train passage

• ensure the detection mechanism is in its proper position and is secure

• check that the stretcher rods securely maintain the open-switch in its correct position and ensure the minimum flange-way clearance is provided

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• check for evidence of excessive movement or wear to the points channel iron or points mechanism and ensure that there is no drifting of the motor/operating bar (points motor latched for EP Claw Lock & EP Spherolock)

• check for evidence of excessive movement or wear to the permanent-way at the points

• inspect condition of parallel bonds including rail connections and retaining clips

16.2. Track circuits at risk

Network control officers treat the operation of track circuits that have not been traversed by rail traffic for 72 hours or more, as unreliable (seldom used) and as such, they manage the rail traffic in accordance with network rules and network procedures.

Additionally, any rolling stock that has the known potential for not providing an effective track circuit shunt is managed by network control officers; for example, block worked in accordance with the Train Operating Conditions (TOC) Manual.

Consideration of these circumstances shall be made by responsible signal engineers, to the affects that these rolling stock have on the operating signalling system, applicable to their area of responsibility.

Where installations provide inherent protection from the risks of rusty rail (for example, axle counters), the signalling may be left fully operational irrespective of the track shunt condition. 02000 ST v4.0, 04/05/2021

16.2.1. The 72 hour rule

The 72 hour period calculation assumes a base-line at which the rail surface condition was relatively free of contaminants and was frequently utilised by rail traffic, such that it provided an effective track shunt, before the 72 hour period commenced. Where the rail condition is in a lesser state, then consideration to reduce the 72 hour period nominated in network rules and network procedures may be proposed as an exception to the general requirement. In such cases, the exception shall be documented and duly issued to the designated network control officer and relevant signalling personnel.

In certain circumstances, the responsible signal engineer may deem it acceptable to extend the 72 hour period, conditional upon an assessment of the engineering risks and operational implications being appropriately mitigated. The determination shall take into account the factors for consideration stated in Section 16.2.3 of this standard. The matter shall then be raised for acceptance with the signal engineer holding accountability on behalf of the operator/maintainer and the appropriate network control officer.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

16.2.2. Identifying and testing track circuits at risk

Where rail traffic has stopped operating for periods greater than 72 hours affecting large areas of track circuited lines, suitable arrangements shall be put in place to identify and test the track circuits at risk.

Periods of non-use can be instigated by possession work, industrial dispute, storm events, security events, alteration to normal timetables or varied freight operations.

Proper and timely notification, liaison and planning with the relevant parties are required to ensure that risks associated with loss of track shunt are managed effectively so as to not cause a reduction in signalling safety.

Examples of trackwork or possession situations which can cause track circuits to be at risk of not providing an effective track shunt include the following:

• track circuits directly worked on during trackwork (for example, installation of new or rusty rails)

• track circuits inside a possession area that are not part of any trackwork

• track circuits outside a possession area that are not traversed due to an operational variance caused by the possession

An inspection and test plan shall be arranged as part of a strategy for testing track circuits for an 02000 ST v4.0, 04/05/2021 effective track shunt following periods of non-use greater than 72 hours.

The method and scope of testing shall vary depending upon the reason for the event, length and track configuration, type of trains in operation, weather conditions and the period of non-use.

Consideration to re-evaluate the testing strategy shall be given if the scope of work or possession arrangement is altered throughout the period of non-use.

Certification of the track circuits and subsequent running of train services shall not exceed 24 hours from the conclusion of testing.

16.2.3. Risk assessment - factors for consideration

The decision to allow signalling to operate over track circuits, relative to the potential loss of an effective track shunt, such as contaminated rail surfaces or poor wheel-to-rail interfaces shall be determined by a signal engineer. Surface contamination matters shall be determined on-site.

Signalling safeworking procedures shall prescribe the factors for consideration, required when determining the option to allow the signalling system to operate in such circumstances.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Examples of factors for consideration include the following:

• capability of an effective track shunt

o type of track circuits in use

o random or loose contaminants causing intermittent loss of shunt

o newly installed or seldom used rusty rail, causing high likelihood for the loss of shunt

• location of contaminated rail

o proximity to clearance points and tuned loops

o length of contamination (equal to a whole train or light engine)

o contamination spanning the entire track circuit

o contamination spanning several track circuits

• environment and configuration

o long straight or tangent track allowing smooth rolling of wheels on rails

o contaminated rails affecting part of a siding or refuge

o contaminated turnout rails which form part of a main-line crossover

o contaminated rails in both turnout and straight rails of points 02000 ST v4.0, 04/05/2021 o points operated remotely or locally from a control panel or adjacent ground frame

o seldom used track circuits that operate level crossing protection equipment

o areas prone to high humidity, excessive rainfall, flooding or temperature extremes

o areas prone to sanding, wheat, coal spillage and the like

o rail susceptible to rusting due to environmental contaminants including ocean salt spray or industrial corrosive fallout

• rolling stock operating on affected line

o electric trains

o mixed trains

o freight only trains

o light engines

o diesel multiple units (DMU) or single unit diesel cars (SUDC)

o typical rolling stock length and consist

o speed of rail vehicles, especially short or light vehicles

o axle loading, number of axles per train and gross tonnage

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

o time and frequency between rail vehicles

o rolling stock with tread conditioning from brake shoes or only disk brakes used

o wheel and rail profile, variance of wheel-to-rail contact band, risk of hollow-wheels

o rail contaminants emanating from rail vehicle

o track circuit shunt assistors used on certain rolling stock to enhance track shunt capability

• maintenance and administrative controls

o effective monitoring

o regular grinding

o utilisation of a temporary stop-block to reduce risk

o specific signal routes left operational subject to an acceptable level of risk

o the arrangement of more frequent services

o determining if manual safeworking operation would cause a higher risk

o determining if blocking facilities applied to signalling controls in lieu of apparatus disconnection would cause a higher risk

determining if a change to the TOC Manual would provide an acceptable risk 02000 ST v4.0, 04/05/2021 o Where adverse conditions continue or where infrequent or light weight traffic services permanently operate, options for engineering design solutions that mitigate the risk of an effective track shunt in these situations shall be sought.

17. Requirements for re-railing and associated trackwork

When re-railing is performed, such that it involves breaking the rails of track circuited or electrified lines, certain elements shall be considered to ensure all the risks associated with the work are understood and controlled.

These considerations shall include the following elements:

• protection of trains

• provision of alternative traction return

• testing of track circuits and associated signalling

• ensuring an effective track shunt

• certification of infrastructure for operational use

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Note: For the purpose of this standard, re-railing includes any trackwork that involves breaking the rail.

17.1. Licensed signalling personnel attendance

Licensed signalling personnel shall attend re-railing when it occurs in any of the following situations:

• where the interlocking will be impacted by the work

• in the vicinity of points located at intermediate sites outside an interlocking

• in plain track areas where the length of re-railing is six metres or more

• at any location on electrified single lines

• in the vicinity of insulated joints, tuned loops, axle counters, ATP balises or any other track interface

• short sections of rail in the vicinity of converging track clearance points

• where the operation of a level crossing will be impacted by the work

• adjacent to substations or sectioning huts

• wherever there is potential for traction bonding or track circuit cabling to be interfered with

02000 ST v4.0, 04/05/2021 by the work

In all other cases, licensed signalling personnel may be exempt from attending re-railing. In such cases, temporary rail bonds shall be issued by signalling personnel to qualified track workers for them to apply. This is done to allow the trackwork, which would otherwise affect operational signalling, to proceed with minimum disruption to rail traffic. The track circuits remain operable by the placement of temporary rail bonds around the rail break. Temporary rail bonds and their placement shall be in accordance with the requirements stated in Section 17.7 of this standard.

When licensed signalling personnel are required to attend re-railing, they shall protect rail traffic and signalling equipment from the work by undertaking the following tasks:

• considering the effects caused on the signalling system by the re-railing

• compiling the infrastructure booking authority

• booking protecting signals out of use

• providing an alternative path for traction return current, as necessary

• disconnecting affected track circuits

• disconnecting associated signalling equipment

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

At the end of re-railing, licensed signalling personnel shall reinstate and test the affected track circuits. They shall also ensure that the rail surfaces are sufficiently clean to provide an effective track shunt. Associated signalling shall be functionally tested before restoring the signalling back into use.

17.2. Infrastructure booking authority requirements

Before commencing the re-railing, an infrastructure booking authority shall be compiled in accordance with network rules and network procedures. Licensed signalling personnel shall be accountable for compiling the authority. Qualified representatives from track and electrical shall also sign the authority as applicable. The signaller shall sign the authority, permitting the work to proceed.

Signalling apparatus shall not be disconnected until the infrastructure booking authority has been signed by the signaller. Trackwork that affects signalling shall not commence until authorised by licensed signalling personnel. This is required to confirm the protecting signals are booked out of use and the alternative traction arrangements are in place, as applicable.

Signatures shall again be obtained at the completion of work before the signalling is deemed operational.

17.3. Protection of rail traffic 02000 ST v4.0, 04/05/2021 The requirements for securing signalling out of use, for the purpose of protecting rail traffic from re-railing, shall be as follows:

• track circuits affected by the re-railing shall be disconnected

• protecting signals that immediately lead toward the tracks affected by the re-railing shall be booked out of use and disconnected

• signals in the rear of the protecting signals shall also be booked out of use where the re-railing affects overlap track circuits

• trainstops that operate in association with protecting signals and affected signals shall be retained in the raised position

In certain cases, trainstops affected by re-railing may be suppressed to facilitate train movements through the re-railing section.

Trainstops suppressed for re-railing shall only be permissible where handsignallers are positioned at affected signals (in accordance with network rules and network procedures) and the track infrastructure, including traction return where applicable, is in a fit state for rail traffic to enter the worksite.

Before implementing trainstop suppression, a signal engineer shall first assess and mitigate the risks associated with the trainstop suppression and then obtain agreement

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

from network operators. The assessment shall include the risk of trains inadvertently passing signals at stop. The outcome of the assessment shall influence the number of trainstops that can be suppressed.

The trainstop at the first approached signal, affected at stop by the re-railing, shall remain in the raised position and not be suppressed. Protection officers shall be advised of all suppressed trainstops within their area of management.

• automatic level crossing protection affected by the re-railing shall be booked out of use

Level crossing protection shall be disconnected if not fitted with master emergency, or other similar manual override facilities. Whenever level crossing protection is disconnected, it shall be functionally tested by operating each approach track circuit in turn, before the level crossing is booked back into use.

Where an affected level crossing is situated on double line areas with automatic signalling, the signals approaching the level crossing on lines that are not affected by the re-railing may be left working if required.

02000 ST v4.0, 04/05/2021 • other trackside signalling equipment affected by the re-railing shall be booked out of use, disconnected and removed clear of the trackwork as necessary; for example, points equipment, ATP balises

17.3.1. Re-railing on bi-directional lines

On lines where the signalling is bi-directional, the immediate protecting signals in each direction shall be booked out of use and disconnected. Signals other than the immediate protecting signals, where affected by the re-railing shall be booked out of use, but may be left connected. This alleviates the need to physically disconnect each intermediate signal within the bi-directional section where it is impractical to do so.

Starting signals that are not directly affected by the re-railing may be left operational.

17.4. Traction return arrangements

The requirements for providing adequate traction return shall be in accordance with Section 18 of this standard. This provision relates to traction return arrangements for work such as re-railing, disconnection of traction bonding or disconnection of negative return cables at substations and section huts.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

17.5. Requirements for newly installed rails

The surfaces of newly installed rails are most likely to be contaminated with protective coatings, rust and other contaminants. Where track circuits are in operation, this poses a risk that trains may not be able to provide an effective track shunt and as such, may not be detected by the signalling system.

Therefore, the surfaces of rails, including the running face, shall be made sufficiently clean along the entire length of track circuit in order to provide an effective track shunt. This shall be done before the protecting signals are restored for operational use.

Following re-railing, the rails shall be cleaned to provide a shiny metallic surface to achieve a good electrical wheel to rail interface. This shall be achieved by the following methods, as applicable:

• Mechanised profile-grinding long sections of newly installed rail. The grinding shall clean any protective coating, rust or other contaminates for the full width of the rail head and along the running face for the entire section of newly installed rail.

• Hand operated rail-grinding short sections of newly installed rail. The grinding shall clean any protective coating, rust or other contaminates for the full width of the rail head and along the running face for the entire section of newly installed rail.

•

02000 ST v4.0, 04/05/2021 Utilising the passage of trains or other rolling stock to provide a satisfactory wear band on the rail surface and running face to achieve an effective track shunt. The trains shall not operate on signals until an effective track shunt is obtained.

A train shunt check shall be performed following the installation of newly installed rails. The trains shall operate under a manual system of safeworking, such as manual block working and not under signals, until an effective track shunt is obtained.

An exemption to the train shunt check requirement may apply in any of the following situations:

• On sections of newly installed rail not exceeding 15 m, where the newly installed rail is at a distance greater than 15 m from any clearance point or adjacent track circuit (insulated rail joint or tuned loop).

In such cases, the exemption means there is no requirement to clean the rail surface.

• On sections of newly installed rail not exceeding 15 m, where the newly installed rail is at a distance of 15 m or less from any clearance point or adjacent track circuit (insulated rail joint or tuned loop).

• In such cases, the exemption shall only apply where the rail surface and running face have been cleaned using a hand operated or mechanised profile grinder. Additionally, an inspection of the newly installed rail surface is done to prove the rail surface and running

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

face are free of contamination. A fixed shunt check is also required on each track circuit affected by the newly installed rail section.

• On sections of newly installed rail exceeding 15 m, where a mechanised profile grinder is used to clean the rail surface and running face and the grinding was completed no more than 72 hours from the time of certification.

In such cases, the exemption shall only apply where an inspection along the entire length of the newly installed rail is done to prove the rail surface and running face are free of contamination. A fixed shunt test is also required on each track circuit affected by the newly installed rail.

Note: Short sections of newly installed rail pose a risk of loss of track shunt. For example, a short section of newly installed rail (two metres or longer) that is located 15 m or less from a clearance point or adjacent track circuit (insulated rail joint or tuned loop). In this case, there is a risk that a bogie of a train can stand on the rusty portion of the new rail and be foul of the converging line or adjacent track circuit. The train can possibly go undetected by the signalling system.

These dimensions are derived from a wheel base of a single bogie that is approximately two metres and the centre line between bogies is approximately 15 m.

02000 ST v4.0, 04/05/2021 17.6. Reinstatement of signalling

Following the re-railing work, the affected track circuits shall be tested in accordance with the track circuit inspection and testing requirements stated in Section 25.3 of this standard. The tests shall be done only after the traction return arrangements are reinstated.

The requirements of a train shunt check in accordance with Section 17.5 of this standard shall apply.

Testing shall ensure that the track circuits operate in accordance with their design requirement and that the polarities, where applicable, comply with the track insulation plan. Additionally, the track circuits shall be tested to ensure that they de-energise with the correct shunt resistance applied (track shunt check) and also when the feed-end power supply is removed (zero feed test).

Where the re-railing affects parallel bonds, the parallel bonds shall be ensured for correct and effective connection after re-railing. The portion of track circuit connected via the parallel bonds shall be shunt tested before the signalling is restored for operational use.

All affected signalling shall be checked to be operational before certifying its use.

The infrastructure booking authority shall be signed by the relevant disciplines to certify their respective infrastructure and then signed by the licensed signalling person to certify the signalling infrastructure. The authority shall then be provided to the signaller for sign-off.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Note: Signing the infrastructure booking authority back into use constitutes certification that the infrastructure is safe for operational use.

The responsible signal engineer shall retain a copy of the completed infrastructure booking authority.

17.7. Control and issue of temporary rail bonds

Temporary rail bonds referenced in this standard are the bonds applied by non-signalling track workers during re-railing. Temporary rail bonds are used when the work necessitates rails to be broken and licensed signalling personnel are not required to attend, in accordance with this standard. These bonds are intended to keep the track circuits working, and maintaining the traction return current, in order to minimise disruption to rail operations.

The following are examples of trackwork where temporary rail bonds are required to be fitted:

• pulling back for expansion or creeping

• welding rail joints

• renewing defective fishplates

• replacing a section of rail less than six metres long

The responsible signal engineer shall issue the temporary rail bonds to track workers on

02000 ST v4.0, 04/05/2021 request. The responsible signal engineer shall gather an understanding of the intended scope of work and then provide clear instruction to the track worker for the correct use and placement of the bonds. The responsible signal engineer shall ensure that the track worker is competent to apply the temporary rail bonds before permitting their issue.

The issue of temporary rail bonds to each trackwork team shall be limited to the following:

• two temporary rail bonds, of a maximum length of two metres each

• two temporary rail bonds, of a maximum length of six metres each

Temporary rail bonds shall be of an approved design, fitted with approved rail clips. Each bond and its associated rail clips shall be uniquely numbered and tagged. The bonds and tags shall be inspected every six months to assess their condition and effectiveness. The responsible signal engineer shall retain a register specifically for the purpose of recording these details.

The responsible signal engineer may delegate these duties to other signalling personnel who are competent to do so. However, the responsible signal engineer shall retain accountability.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

17.7.1. Specific restrictions for use

The instruction to track workers applying temporary rail bonds shall include the following restrictions where applicable:

• In double rail ac track circuit areas, temporary rail bonds shall only be placed around the rail break when done in conjunction with shorting bonds. These shorting bonds shall be placed across the rails on both sides of the break.

• In electrified track circuited areas, only one rail of a track shall be broken at any one time. For example, it is not permissible to break both rails of the same track at the same time. It is also not permissible to have more than one break in each rail.

• In non-electrified track circuited areas, no more than two rails of a track shall be broken at any one time. However, it is not permissible to have more than one break in each rail at the same time. For example, it is permissible to have a break in both (opposite) rails of a track simultaneously, but no other breaks can be made at that time.

18. Requirements for providing adequate traction return

Adequate provision for the safe return of traction return current shall be considered and

02000 ST v4.0, 04/05/2021 implemented before performing work that affects its path to the substation or section hut.

The following types of work have the potential to impact the return path of overhead traction current:

• re-railing in electrified areas

• disconnection of traction bonding including impedance bonds

• disconnection of negative return cables at substations and section huts

Alternative traction return arrangements shall be made to mitigate the risks associated with rail breaks, disconnected traction bonds or negative return cables. This is done to ensure unsafe voltages do not develop across the rails or cables.

Similarly, signalling equipment shall be safeguarded against damage caused by the potential rise in traction return voltage.

In many cases, particularly where complete tracks are removed, the alternative arrangements can include isolation of the overhead. Where this is the case, the effects of live overhead that are adjacent to the isolated section shall be considered.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

18.1. Exemption to providing alternative traction arrangements

Implementing alternative traction arrangements may be exempt in certain circumstances on the following conditional requirements:

• ensure traction bonding in the vicinity (on both sides) of the intended work complies with the specific track insulation plan

• ensure traction bonding in the vicinity has sufficient capacity to safely return the additional traction return current

These conditions shall be validated by physical inspection of the traction arrangements to confirm their condition and compliance.

Where the exemption applies, only one rail break shall be permitted in each traction rail.

The following circumstances state where the exemption from providing alternative traction arrangements can apply:

• On lines where there are three or more traction rails in the same corridor that provide the traction return path to a substation or section hut. In this case, one traction rail may be broken without providing alternative traction arrangements.

• On lines where there are six or more traction rails in the same corridor that provide the 02000 ST v4.0, 04/05/2021 traction return path to a substation or section hut. In this case, two traction rails may be broken without providing alternative traction arrangements.

18.2. Work affecting negative return at substations or section huts

Where re-railing, or disconnection of traction or negative return cables is done adjacent to substations or section huts, at least one effective negative return cable shall be retained during the work. This is done to ensure that unsafe voltages do not develop across rail or cable breaks.

The following requirements shall be met for undertaking re-railing, or disconnecting traction bonding or negative return cables adjacent to substations or section huts, as applicable:

• Where substation or section hut negative return cables connect to both sides of a mechanical joint in single rail track circuits, the re-railing shall be done in two stages.

The first stage shall include re-railing only to one side of the mechanical joint. After the negative return cable of that portion is reinstated, the remainder of the re-railing shall be carried out as the second stage.

• Where substation or section hut negative return cables connect to plain rail (no mechanical joint) in single rail track circuits, the rail shall be first cut so that both negative return cables are not disconnected simultaneously.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The first stage shall include re-railing only to one side of the rail cut. After the negative return cable of that portion is reinstated, the remainder of the re-railing shall be carried out as the second stage.

• Where substation or section hut negative return cables connect to impedance bonds in double rail track circuits, the re-railing shall be undertaken on only one rail at a time. During this time, the other rail shall remain fully bonded with its negative return made via the impedance bond.

Where the above requirements are impractical, the overhead traction shall be first isolated before commencing the work; for example, when the complete track is required to be removed.

The electrical operation control centre shall be notified of the intention to disconnect any substation or section hut negative return cables before the work commences.

18.3. Work affecting impedance bonds

Before an impedance bond is disconnected, the feed and relay of the affected track circuit shall be isolated from the track. Temporary bonding shall be provided for the traction return path between the affected track circuit and the adjacent track circuit traction return path.

18.4. Temporary rail connections for overhead wiring

02000 ST v4.0, 04/05/2021 Temporary rail connections are permitted for the temporary earthing of overhead wiring. These are additional to any permanent rail connections which are provided in accordance with signalling designs for installed overhead sectioning and earthing switches.

When temporary rail connections are requested, a signal engineer shall nominate the location for the connection and provide a marked-up copy of the specific track insulation plan. The connection shall be made only on the traction rail of a single rail track circuit or the neutral point of a double rail track circuit. Where the operation of the track circuit is not required, the connection may be made on any of the traction rails.

In cases where the operation of a track circuit is affected by the temporary earth connection, the track circuit shall be disconnected and the associated signalling shall be booked out of use.

Temporary rail connections shall be made by a secure connection and located clear of any trackwork taking place.

19. Minor signalling additions, alterations and renewals work

Sustaining the integrity of the operating signalling system at all times is an unconditional requirement. This is particularly relevant during signalling additions, alterations and renewals work where the risks from interference caused by the work are increased.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Note: Alteration work includes the installation of any temporary repairs.

All persons performing such work shall be aware of the potential impact of the work they perform, including the effect on adjacent running lines or operational equipment in close proximity to the work area. Signalling that has been tested and certified, pending being brought back into use, shall be secured and treated similarly as if it were operational equipment.

Any work which has the potential to impair the integrity of the signalling shall be booked out of use, including the signals in the rear of the affected equipment.

Work on signalling equipment which involves disconnection, disarrangement, disassembly, adjustments, alterations or additions shall be planned and performed with adequate controls in place. This shall include thorough testing at the completion of the work commensurate with associated risks. These risks can include incorrect connection, polarity reversal, wrong assembly, incorrect type or configuration, improper adjustment and so on. This shall be assessed and then mitigated by suitable testing in accordance with SPG 0711.

A functional test of the apparatus shall always be included in such testing.

19.1. Risk mitigation requirements for minor additions, alterations or renewals

Risk mitigation requirements for minor additions, alterations or renewals shall be prescribed in

02000 ST v4.0, 04/05/2021 signalling safeworking procedures.

The following are examples of risk mitigation requirements to be included in signalling safeworking procedures for minor additions, alterations or renewals, as applicable:

• electrically isolate the live circuitry of affected signalling from the worked-on portion

• ensure signalling documentation used reflects the latest design

• correlate the existing arrangement, which includes apparatus inspection, wire and null count to ensure that the installation reflects the specific as-built design before commencing work

• secure and insulate unterminated wires, including spare cable cores in such a way that they are unable to make contact with any conductive surface or electrical component

• not connect wires or equipment pending commissioning to working circuits, and as such shall require two points of connection to take effect

• not leave connected wires and equipment decommissioned from use, to working circuits or power supplies

• label and tag wires and corresponding terminals before connecting or removing

• treat metal links as wires, particularly when wire/null counting

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• disconnect and reconnect only one single wire or one cable type (where the individual cores can be easily identified) at a time, where possible

• mark matching sides of equipment including air hoses before disassembly

• provide a unique and distinct colour for temporary wiring used on each stage or testing purpose

• comply with the required standard for the specific location including wires, cable cores, contacts and other items of equipment which will be utilised in new or altered circuits

• update accordingly, the signalling documentation at the end of each commissioned stage

• ensure personnel are competent for the task

• comply with the testing and certification requirements of SPG 0711

• ensure adequate lighting and access

• remove distractions or causes of pressure

• apply a methodical and systematic approach

• maintain proper housekeeping of the work area and ensure that the housing and all equipment are made secure when vacated

02000 ST v4.0, 04/05/2021 19.2. Involvement of signal engineer for risk mitigation requirements

A signal engineer shall be associated with every signalling addition, alteration or renewal. The level of association shall depend on the risks associated with the work and the authority level of the signalling personnel performing the work, which includes inspection, testing and certification.

Examples of such cases are listed below:

• signal engineer signs off the scope and authorisation form for a like for like renewal

• signal engineer authorises a like for like renewal where the equipment is not exactly identical

• signal engineer is advised of rewiring

• signal engineer performs inspection and testing of signalling additions or alterations

• the responsible signal engineer is consulted when adjustment made beyond specified or expected limits

• the responsible signal engineer notified when temporary repairs are effected

• the signalling commissioner commissions new or altered signalling

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

19.3. Work not affecting the design principle

Licensed signalling personnel are permitted to perform some alteration work on the signalling system, without the direct involvement of a signal engineer, where the work does not alter the design principle.

The following are the tasks that can be performed by licensed signalling personnel:

• Transfer of a circuit from a defective contact, terminal, cable core or wire to an equivalent spare in order to rectify a failure scenario. The wiring work shall be limited to removing one single wire or cable type at a time. This work shall be treated as a temporary repair in accordance with Section 12.3 of this standard.

• Replacement of signalling equipment with an identical type. The like for like renewal requirements stated in Section 19.4 of this standard shall be observed.

• Replacement of consumable or sub component items, where there is minimal risk of error. These items include pluggable apparatus that are indexed against incorrect insertion. This work may be exempt from meeting the like for like renewal requirements.

The following are examples of consumable or sub component items that may be exempt from the like for like renewal requirements:

• fuses and terminals 02000 ST v4.0, 04/05/2021 • power supply units, transformers, capacitors, rectifier units

• mechanical pins, bushes, fasteners and minor mechanical components such as cranks, rods, economical movements, detector ball joints, extension irons

• contacts where fitted with a pluggable wiring loom or individually wired

• plug-in relays, track circuit transmitters and receivers

• trainstop limit switches, motors, older style contact fingers, trip arms, detector arms

• electric point motors, capacitors, clutches, mechanisms, older style contact fingers

• signal lamps, signal LED boards, signal lenses

• level crossing booms, lights and bells

• signalling controls and indications such as push buttons, switches and diagram lights

Precautions and adequate testing shall be prescribed in signalling safeworking procedures to ensure that there is no alteration to the circuit, or changes to polarity, operating parameters or settings, configuration or design principle. Additionally, a functional test shall be performed before certifying every case.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Whenever a signalling power supply or its related wiring to polarity-sensitive equipment (for example, 50 Hz ac track circuits) is worked on, care shall be taken to ensure that the polarities are not reversed.

Adjustments made to vital signalling equipment beyond the specified or expected limits shall be first approved by the responsible signal engineer or signalling commissioner before bringing the equipment back into use. All adjusted equipment shall be tested in situ.

19.4. Like for like renewal work

Like for like renewal refers to the replacement of an item with an identical item. It can also refer to an item that is not identical where it is deemed acceptable by a signal engineer on the following basis:

• the replacement item is of similar characteristic, footprint

• where the difference does not diminish the intended design principle

The like for like renewal requirements shall generally pertain to the renewal of trackside apparatus such as electric point mechanisms, electro-pneumatic point equipment, mechanical point components, signals, trainstops, vital shelf relays, releasing switches, level crossing mechanisms and similar items.

Examples of electro-pneumatic point equipment include detectors, escapement slides, plunger 02000 ST v4.0, 04/05/2021 lock assemblies, indication boxes, air motors, and control units. Mechanical point components include point lock assemblies, detectors and compensators.

The like for like renewal requirement shall also pertain to trackside equipment that is temporarily removed such as work that involves the removal of the wiring or cable which connects the equipment to the interlocking. For example, a trainstop that is disconnected from its cable (and air supply if applicable) and removed clear of its mountings to facilitate trackwork.

It is not a necessary requirement for signalling commissioners to certify and commission like for like renewal work. However, only licensed signalling personnel competent to perform the activity of like for like renewal without supervision, shall lead such work.

Like for like renewal procedures shall be included in signalling safeworking procedures to provide licensed signalling personnel with suitable documentation. This aims to ensure that all the required tests and checks are complete before permitting the replaced signalling equipment back into use.

Like for like renewal work shall be performed in accordance with a scope and authorisation form and specific work instructions.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

A scope of authorisation form shall consist of the following key elements:

• details of the work scope and type of equipment

• location of work

• commencement date and time, and completion date and time

• listing of documents required in the work package as referenced in Section 19.4.1

• provision for dates and signatures of the authorising signal engineer, responsible signal engineer and equipment certifier

A work instruction shall consist of the following key elements:

• description of the specific equipment type

• date of work

• references to relevant signalling safeworking procedures and standards (including inspection and testing standards)

• step by step description of the entire renewal work, including the following elements:

o apparatus inspection and preparation

o signalling safeworking requirements including disconnection from interlocking

02000 ST v4.0, 04/05/2021 o electrical, pneumatic, mechanical disconnection, removal and installation

o apparatus adjustment and lubrication (as applicable)

o all required inspection and tests

o certification (including an explicit statement of actual work certified)

• equipment certifier's name, role, signature and date

The work instruction shall be specific to the equipment renewed. Progressive entries shall be made against each completed task by the signalling person performing the work.

Where multiple items of equipment are combined on the same work instruction, each task of every equipment item shall be separately and clearly shown. Additionally, every equipment item shall be specifically signed-off to attest its final certification prior to booking the affected signalling into use.

Where a work instruction for the specific equipment type is not formally available, a signal engineer shall provide the necessary instruction pertaining to the work to mitigate the associated risks.

Note: Samples of the scope and authorisation form and work instructions are available in SPG 0711.These documents may be replicated for inclusion in signalling safeworking procedures by the operator/maintainer if desired.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

19.4.1. Work package for like for like renewal

A work package shall be compiled for like for like renewal work.

This work package shall consist of the following documents:

• scope of work and authorisation form

• relevant work instruction

• signalling plan extract as applicable

• circuit diagram and analysis pages as applicable

• infrastructure booking authority

• bridging authority form with its own circuit diagrams as applicable

• certification returns and other required certificates as applicable

Each page of the work package shall be numbered and the total number of pages shall be shown on the cover.

The circuit diagrams and signalling plans shall be printed copies of the as-built circuit book or signalling documentation for the area and not hand drawn copies. Care shall be taken to ensure that these reflect the latest installed design, including any interim maintenance copies that can apply. Part circuit diagrams shall be marked with the circuit book page and identification 02000 ST v4.0, 04/05/2021 number, or job number if an interim maintenance copy is used. Disconnection of circuits shall be marked on the circuit diagrams.

All work shall follow the work instruction procedure. All testing shall be documented on the work instruction, circuit diagram, analysis page and signalling plan, as appropriate.

All inspection and tests stated in the work instructions shall comply with the suite of tests prescribed in SPG 0711 and signalling safeworking procedures (for example, point lock testing requirements).

The completion time shall be noted on the scope and authorisation form upon completion of the work. The work instruction and any document where testing notations have been made, such as the signalling plan or circuit diagram, shall also be signed. The completed package shall be forwarded to the authorising signal engineer for reviewing, taking action on any asset update requirements, and archiving.

19.4.2. Authorisations required by signal engineer

Where an item intended for installation is not exactly identical as the item being replaced, the difference between the equipment types, the effect on the design principle, and the risks associated with the changed configuration shall be assessed. A signal engineer shall be required to assess and authorise the renewal work in these circumstances.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following examples are of like for like renewals, where signal engineer authorisation is required:

• newer version of a point machine replaces an earlier version

• renewal of similar equipment where later versions alter the terminal arrangement

• trainstop with enclosed contacts replaces trainstop with open contacts

• point machine changed on a triple-end or independent switches (additional out of correspondence test required)

• more than one point machine is changed within the layout

• shelf relay replaced by a plug-in relay conversion unit

• partial renewal where not all elements are replaced and only a subset of the work instruction are applicable

• renewal of equipment where a formal work instruction does not cater for the particular type of work

Where an authorisation is granted, the scope of work and authorisation form shall include a description of the difference between the equipment types and a listing of any subsequent actions. The subsequent actions can include updating the asset register, marking-up and signing the field certified office copy, submission of the certified office copy for updating, and 02000 ST v4.0, 04/05/2021 arranging additional training for signalling personnel. Any pending actions following the authorised renewal of equipment not exactly identical shall be promptly closed-out.

Additionally, the scope and authorisation form shall be signed by the signal engineer before commencing the work. In cases of emergency, the signal engineer may provide the authorisation remotely, and provide the signature at the earliest opportunity.

Notwithstanding these requirements, a signal engineer's authorisation for like for like renewal can be omitted where the items for renewal are exactly identical and a formal work instruction caters for the particular type of work. A submission of the work package is still required to the authorising engineer at the end of the work.

19.4.3. Granting pre-authorisation for like for like renewal work

A signal engineer may consider pre-authorising routine equipment changes in advance of an event. The pre-authorisation shall be documented by providing appropriate local procedures attached to the relevant work instruction. The local procedures shall mitigate the additional risks associated with the equipment difference.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following are examples where pre-authorisation may be granted for a like for like renewal:

• newer version of equipment replaces an earlier version (including trainstops and point machines)

• a point machine is changed on a triple-end or at independent switches

• shelf relay replaced by a plug-in relay conversion unit

19.5. Work affecting the design principle

Additions, alterations, or renewal work that does not meet the requirements for like for like renewal, or any other work that alters the intended signalling design principle or configuration shall proceed only when issued with an approved design. Approved designs are issued by the AEO engaged to provide the design assurance accountability. A signalling commissioner shall be assigned to lead this work and the work shall be done in accordance with SPG 0711.

The following are examples where work shall be treated as an alteration, done as a commissioning, and not as a like for like renewal:

• conversion of incandescent signal to LED type

• replacement of LED signal with a different LED type

• upgrade of conventionally operated points to Claw Lock or Spherolock type 02000 ST v4.0, 04/05/2021 • change of track circuit type

• installation of repeat relays

19.6. Rewiring and wire repair requirements

Whenever wires or cables are in need of replacement or repair, extreme care shall be taken to ensure that the conductors are not cross connected or the circuits not interconnected.

The affected signalling equipment and protecting signals shall be first booked out of use before commencing rewiring or repairs to wiring that can possibly affect working circuits.

Licensed signalling personnel are permitted to perform rewiring or repair of working circuits to alleviate a failure situation. The work shall be carried out on one single wire or cable type at a time. The different cable types shall be easily recognisable by licensed signalling personnel so as to avoid confusion when reconnecting.

Only signal engineers or signalling personnel competent to hold the role of circuit tester are permitted to lead testing, where the work exceeds repairing or replacing one single wire or cable type at a time.

In all cases, the affected signalling and protecting signals shall be booked back into use only by licensed signalling personnel.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Wires and cables shall be correlated to ensure that there are no unintended intermediate contacts, terminals or cables entering intermediate locations, and thus is in accordance with the specific design. The old wires and new wires shall be labelled accordingly with the identity of their respective terminals.

All wiring connections shall be made secure, reliable and electrically insulated from other conductors, live terminals and earth. Rewiring and repairs not performed to the required standard for the specific location shall be treated as a temporary repair in accordance with Section 12.3 of this standard.

The rewiring or repair shall be inspected and tested in accordance with SPG 0711 before returning the affected signalling back into use.

Signalling safeworking procedures shall contain wire replacement and repair procedures for licensed signalling personnel to follow, where permitted by this standard to perform such work.

19.6.1. Additional testing requirements for specific situations

In addition to the normal testing requirements stated in SPG 0711, the requirement of specific testing shall be included in signalling safeworking procedures to mitigate risk that pertain to the following situations:

Signalling cables damaged by excavation works 02000 ST v4.0, 04/05/2021 Where multi-core cables are damaged by excavation works or similar, there is a risk that the insulation between the conductors can get damaged. This can cause a short circuit current flow over a sustained period which can lead to deformed Q type BRB 930 relay contacts.

Where the sustained short circuit period exceeds one hour, a signal engineer shall consider the consequential risk of the sustained short circuit current flow. If determined necessary, the signal engineer shall mandate, in addition to the normal testing requirements, the testing of all relay contacts in the affected circuits on the fuse or supply side of the damaged cable. This testing shall be conducted by either of the following two methods:

• test the affected relay in a relay test panel to ensure that all contacts operate (open and close) in accordance with their configuration type

• functionally operate the relays in the affected circuits to ensure that they are effective in each circuit function as designed (circuit function test)

Track circuit wires replaced

Licensed signalling personnel are permitted to repair or replace two or more track circuit leads to a track circuit location by changing over one single wire or associated pair at a time.

Superseded by T HR SC T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The work shall be tested to ensure the following:

• wires have not been cross connected

• track circuit relay de-energises with the correct shunt applied across the rails

• polarity of the track circuit, where applicable, is in accordance with the track insulation plan

A shunt test of adjacent track circuits shall also be performed. 04/05/2021

Where cut tracks are involved, a shunt test shall be performed to ensure that the track voltage of the adjacent cut track is removed during the shunt.

Signalling data communication links replaced v4.0, Data communication links are utilised to connect vital and non-vital systems such as Microlok II, Solid State Interlocking, Dupline, Kingfisher, SCADA and other such systems. These links consist of either copper communication type cables or optical fibre conductors. ST When changing a spare pair in a copper communication type cable or optical fibre conductor, the logically correct pair at both ends shall be first established, followed by an end-to-end continuity test, before certifying the signalling back into use.

19.7. Documents used for the certification of signalling

02000 Except as provided for in the like for like renewal requirements, provision for the certification of signalling shall be achieved by completion of the following signed documents, as applicable:

• infrastructure booking authority SC • interlocking certificate, design integrity test certificate

• maintenance record; for example, point lock return, insulation test record, track circuit record, relevant inspection and test form (ITF) HR • certified office copy circuit book, signalling plan, track insulation plan, control table, locking

T table or working sketch

• other documents used by the AEO acting on behalf of the operator/maintainer for the

by purpose of certification

19.8. Paralleling of contacts in trackside apparatus

The paralleling of contacts used for the detection or operation of signalling apparatus, with associated spare contacts, is permitted and may be performed ahead of obtaining approved signalling documentation.

Licensed signalling personnel are permitted to perform such work where it is deemed necessary to improve the reliability of trackside signalling. The wire and termination means used to parallel the contacts shall be consistent with the wiring already in use, with a limit of two wires

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

terminated at each terminal. The parallel wires shall be labelled with the letters 'PC' to identify their purpose until specific circuit books are updated accordingly.

A test shall be performed to ensure that the original design function of the contact has not been defeated by the work and also to ensure the effectiveness of the paralleled contacts.

The responsible signal engineer shall be notified of all such contacts paralleled and

04/05/2021 subsequently, shall make the necessary arrangements to update the specific circuit books. The local circuit book shall be duly marked-up to indicate the paralleled contacts, until the updated circuit books are issued.

20. Requirements and scheduling of signalling v4.0, maintenance

The signalling system and its associated equipment shall be maintained to ensure the availability of the asset, and its reliable operation to safely and efficiently regulate train ST movements, in accordance with its design.

Signalling maintenance shall be performed on the whole signalling system and where applicable, shall include trackside communication equipment. The work shall be done in accordance with signalling safeworking procedures, network rules, network procedures, signalling technical maintenance plans, engineering instructions, equipment manuals and

02000 transport standards as published on the ASA website.

The responsible signal engineer shall be advised of any maintenance or signalling safeworking matter requiring their attention or escalation. The urgency of the advice shall be treated

SC accordingly.

The responsible signal engineer shall be accountable for ensuring that all aspects of signalling maintenance are executed. This shall be done by taking into account the asset condition and

HR site specific conditions that can require the asset to receive more rigorous, frequent maintenance, inspection and testing. This is particularly required where these conditions have

T the potential to impair the safety of the signalling system.

Where the safety provided by an asset is impaired, the responsible signal engineer shall take

by the necessary action to mitigate such risk associated with the situation or otherwise arrange to book the affected signalling out of use.

20.1. Maintaining operational signalling equipment

When intending to perform maintenance work on operational signalling equipment that can affect its safety or reliability, the licensed signalling person shall advise the signaller of the nature of the work and nominate the equipment affected. This shall be done before commencing such work.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Examples of affects to signalling caused by maintenance work include the following:

• indications of signals changing for approaching trains

• indications of signalling displayed incorrectly at signal boxes or control centres

• level crossing protection operation is activated without an approaching train

Maintenance work that impairs the safety of the signalling shall be protected, in accordance with 04/05/2021 securing signalling apparatus out of use, as stated in Section 13 of this standard, before commencing the work.

Any signalling equipment worked-on shall be functionally tested before leaving the worksite to ensure that there are no adverse effects on its operation at the end of the work. This v4.0, requirement extends to the removal or disturbance of any signalling apparatus such as ESML or EOL keys, relays, fuses, links, switches, opening of electrical contacts and so on.

During maintenance visits, signalling personnel shall be vigilant of any potential failure ST situations. This shall include a check of signalling equipment where there is reasonable cause to suspect the reliable operation has been jeopardised by construction activity, mechanised track maintenance or similar activities. Track circuit parallel bonding, obvious signal sighting obstructions and rail surface condition shall form part of this vigilance.

20.2. Safety related examinations 02000 Signalling safeworking procedures shall include a system of managing and reporting compliance for nominated signalling maintenance tasks defined as safety critical and safety significant. These tasks aim to manage a situation where functional failure or secondary SC damage of an asset can result in a signalling irregularity.

20.2.1. Safety critical task HR A safety critical task is one that protects against a wrong side failure mode in a safety related asset or component, such that if a failure were to occur, it would have a high probability of T causing an outcome of severe consequence.

For example, points are identified as safety critical assets and are allocated safety critical tasks by of gauging the gap between switch and stock rails to check the go/no-go settings of the point lock and point detection. These tasks are done to ensure that the point lock and point detection settings have not drifted beyond their specified limits.

The risk increases when the safety critical tasks are extended beyond the specified period without defined and approved risk mitigation measures in place.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Signalling safeworking procedures shall classify the following tasks as safety critical:

• periodic safety inspection of 50 Hz ac double rail track circuits

• periodic testing of point locks and point detection

• periodic testing of selectors and bolt locks

• periodic testing of unproved electric locks 04/05/2021

• periodic inspection of unproved vital signalling relays – ac vane and dc shelf types

20.2.2. Safety significant task

A safety significant task is one that protects against a wrong side failure mode in a safety v4.0, related asset or component, such that if a failure were to occur, it would have a medium to low probability of causing severe consequences. This is enabled by the provision of additional safety barriers. ST For example, track circuits are identified as safety significant assets and are allocated safety significant tasks of performing a shunt test, zero feed test and polarity test (where applicable). These tasks are done to ensure that the track circuit characteristic has not drifted beyond its specified limits, and ensure that it cannot be falsely fed from another source.

Safety significant assets are slower to manifest themselves and are less likely to be adverse

02000 following the breach of the defined conditional criteria.

Signalling safeworking procedures shall classify the following tasks as safety significant:

• signal engineer’s periodic inspection and testing of signalling interlockings and mechanical SC locking items

• signal engineer’s periodic inspection of level crossing protection equipment

HR • periodic testing of signalling electrical conductor-insulation resistance

• periodic testing of electro-mechanical and thermal type time limit relays T • periodic overhaul of non-proved vital signalling relays – ac vane and dc shelf types

• periodic testing of dc type track circuits by

• periodic inspection of parallel bonds

• periodic track circuit shunt testing, zero feed testing and polarity testing where applicable

• periodic testing of slip detectors and rain-fall detectors

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

20.3. Maintenance scheduling, reporting and recording

A maintenance management system shall be used to schedule all signalling safety critical, safety significant, and other signalling periodic maintenance tasks. Work orders shall be generated by the maintenance management system in accordance with the signalling technical maintenance plan. 04/05/2021 The maintenance management system shall highlight in particular, the compliance of signalling safety critical and safety significant tasks.

Apart from the compliance requirements, safety critical and safety significant tasks shall require specially attested returns from licensed signalling personnel to provide verification of v4.0, certification. A specific format for the return shall be arranged by the AEO acting on behalf of the operator/maintainer. Returns shall be duly submitted to the responsible signal engineer for review of the certification and compliance elements and actioning any necessary items. ST An additional return shall be required for any out of course safety critical or safety significant adjustment or test made between periodic maintenance inspections.

Other such records (for example, relay records, battery records, track circuit records, insulation test records, signal inspection and test records) shall be kept on-site as applicable and also with the responsible signal engineer or maintenance depot. 02000 20.3.1. Maintenance schedule period latitudes

The signalling technical maintenance plan defines the tasks and schedules for signalling infrastructure maintenance. Maintenance frequencies shall comply with the frequencies stated SC in the signalling technical maintenance plan and this standard where defined for safety critical and safety significant tasks. Each task may have a planning latitude which reflects the permitted variation around the task due date. Planning latitudes shall be no greater than 20% for tasks

HR with a frequency of up to 42 days, and no greater than 10% for tasks with a frequency of beyond 42 days, unless authorised by the ASA. T Safety critical and safety significant tasks shall be completed within the defined planning latitude. by Safety critical and safety significant tasks not achieved by the due date and latitude period shall be risk assessed by the responsible signal engineer and the risks appropriately and promptly mitigated. Failure to secure prompt appropriate risk mitigation shall warrant the particular asset and associated assets to be booked out of use.

The non-compliance of other signalling maintenance tasks that are not safety critical or safety significant shall be managed in accordance with the AEO's engineering management system. However the risks associated with the safety elements of these tasks shall be considered and prioritised by the responsible signal engineer.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

21. Inspection and testing of vital signalling relays

Vital signalling relays are integral to the safety and reliability of interlockings. Their critical applications include control, indication, locking, operation, detection and timing. The safety assurance aspect of vital signalling relays requires a thorough understanding and management of the various failure modes and associated risks. Persons working on vital signalling relays

04/05/2021 shall take the necessary precautions when wiring, inspecting, maintaining, replacing, and overhauling. These safety assurance requirements shall be included in signalling safeworking procedures.

Vital signalling relays exist in various forms and configurations, but all are categorised as either proved (proved in the de-energised position by the signalling design) or unproved. Unproved v4.0, relays pose a greater risk, as a wrong side failure associated with these relays can go undetected by the system.

ST All vital signalling relays shall be supplied sealed to prevent unauthorised tampering. Any vital signalling relay in service that is not sealed shall be treated as being sealed and not to be opened. The seal shall not be broken in the field except in exceptional circumstances and only as directed by a signal engineer.

Plug-in conversion units, using Q type BRB 930 relays, are available as a replacement for ACVL relays, and any ACVL relay determined for replacement shall be replaced with the

02000 conversion unit. For each replacement, a notice of installation advice shall be completed and submitted for the purpose of circuit book update. Once installed, the conversion unit may be considered as a plug-in relay for maintenance purposes.

SC Note: Conversion units have a contact current capacity of only three amperes.

21.1. Precautions and requirements for vital signalling relays

HR Precautions and requirements for vital signalling relays shall be prescribed in signalling safeworking procedures. T The following are examples of precautions and requirements for vital signalling relays:

• Vital signalling relays shall be inspected and tested before they are placed into service for by correct operation and configuration (voltage, type, contact configuration, and coding) in accordance with the specific signalling design. The relay shall also be closely inspected for any transit damage.

• The tampering of coding holes in bases or coding pins in relays shall be strictly forbidden.

• The signalling associated with circuits that pass through shelf relays that are not fitted with a detachable top shall be booked out of use before replacing.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• The circuits that pass through replaced relays shall be functionally tested. Any wiring disturbed shall be wire and null counted.

• The replacement task of shelf relays shall be wholly performed by one person and not transferred to another person part way through the work.

• The change details of replaced shelf relays, VT1 relays, electro-mechanical and thermal

04/05/2021 timer relays, and large plug-in relays shall be duly recorded and a notice of relay change submitted to the responsible signal engineer.

• Relay wiring shall not be altered contrary to the specific signalling design unless transferring to a spare contact for the purpose of temporary repair during failure situations. Care shall be taken to ensure the contact configuration is not changed by the transfer. v4.0, Temporary repair requirements stated in Section 12.3 of this standard shall apply.

• Timer relays shall not be adjusted contrary to the time noted on the specific signalling

ST design.

• Magnetically latched relays shall only be inserted into service while in the de-energised position. Under no circumstances shall they be inserted while in the energised position. Before interfering with these relays (typically NLR/RLR), the protecting signals and any other affected signals shall be placed at stop, and all approaching trains ensured to have come to a stand at the signals, with no train foul or passing over any affected points. 02000 • Double element ac line relays may be replaced with a single element type and vice versa provided the local and control coils are correctly bridged in parallel as required in the specific signalling design. SC • DC shelf relays and dc large plug-in relays shall be bench tested for pick-up, drop-away and working currents before being placed into service.

• AC shelf relays fitted with black coils without coil formers shall not be used, as these relays HR can release wax from the coils when hot.

T • Signal branch type dc shelf relays shall not be used.

• Single stranded wire (1/1.70 mm or similar) only shall be used on shelf relays that are not

by fitted with a detachable top. Flexible stranded wire (9/0.40 mm or similar) may be used on shelf relays fitted with detachable tops.

21.2. Storage and reuse of vital signalling relays

Vital signalling relays shall be handled, transported and stored with care, and not subjected to any damage or deterioration. The relays shall be stored in an upright position and not placed on floors prone to dust particles and contamination.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The armature securing screw, provided on shelf relays to prevent transit damage shall be removed before use.

Refurbished vital signalling relays shall be retested for correct operation and contact effectiveness when they have exceeded their storage period. Retesting shall be conducted using an approved relay go/no-go tester that cycles the relay operation while measuring the contact resistance. 04/05/2021 The storage period for refurbished relays is as follows:

• Q type BRB 930 relays – seven years

• ac plug-in relays – three years v4.0, • dc shelf relays – five years

• ac shelf relays – three years

ST New Q type BRB 930 relays, stored in original packaging may be exempt from retesting requirements subject to the relays passing a visual inspection and operation in a conventional relay test panel (which indicates relay contact status).

Used Q type BRB 930 relays with up to 10 years' service may be considered for reuse, on condition that the relay is inspected to be in proper condition (including seals intact, coding pins straight, plug in contacts not bent, no evidence of corrosion or foreign matter, and transparent

02000 cover). Additionally, the relay shall pass a functional test in an approved relay go/no-go tester.

Q type BRB 930 relays with a contact resistance greater than 2 ohms shall not be used except in cases of emergency, as a temporary measure, on condition that the resistance is not greater

SC than 7.5 ohms. In such cases, temporary repair requirements in accordance with this standard shall be complied with.

HR 21.3. Maintenance and overhaul of vital signalling relays

The periodic inspection of unproved vital signalling ac vane and dc shelf relays shall be treated T as a safety critical task in accordance with Section 20.2 of this standard.

The testing of electro-mechanical and thermal type timer relays shall be treated as a safety by significant task in accordance with Section 20.2 of this standard.

The replacement for overhaul of unproved ac vane and dc shelf relays shall be treated as a safety significant task in accordance with Section 20.2 of this standard.

Any vital signalling relay, including spare relays, found with a defect having potential to impact on its safe operation shall be promptly brought to a signal engineer's attention and the signalling shall be protected accordingly.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

21.3.1. Inspection requirements for ac vane relays (all types)

AC vane relays shall be periodically inspected for abnormal operation in accordance with the signalling technical maintenance plan. However, the period between inspections shall not exceed 52 weeks.

The following inspection criteria for ac vane relays shall be included in signalling safeworking

04/05/2021 procedures:

• ensure correct operation, condition of contacts, terminals and pigtails

• inspect for correct release (not sluggish or jerky) and not failing to return fully to the stop position due to defective bearings, warped bakelite tops, wax or other foreign matter in the v4.0, bearings or vane obstructions

• inspect for foreign matter, flaky plating or paint inside the relay

• inspect for deposits of wax, varnish or paint on the vane which can indicate overheating of ST coils or contact with pole faces

• inspect for scratches or abrasions on the vane which can indicate that the vane is distorted or air gap tolerances are incorrect

• inspect vane for spread due to striking the bottom of the relay case (detected by a mark in the paint of the case bottom or jamming on the pole faces) 02000 • inspect vane spindle for any accumulation of dust or discolouration which can be attributed to wear of the bearings or evidence of wax deposits

SC • inspect roller stops for evidence of grooving

• inspect for evidence of grooving on spring type stops to ensure that the spring is effective and not fouled by its bracket when the relay is energised

HR • ensure vane is positioned centrally between (and clear of) pole faces

T • ensure ends of split pins are properly spread

• ensure counter weight lock-nut is locking the counter weight and it has not shifted by 21.3.2. Inspection requirements for dc shelf relays

DC shelf relays shall be periodically inspected for abnormal operation in accordance with the signalling technical maintenance plan. However, the period between inspections shall not exceed 52 weeks.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following inspection criteria for dc shelf relays shall be included in signalling safeworking procedures:

• ensure correct operation, condition of contacts, terminals and pigtails

• inspect for correct release and ensure the armature is operating freely and drops away promptly when the relay is de-energised – check for defects or wax or foreign matter in the

04/05/2021 bearings

• inspect for foreign matter or flaky plating or paint inside the relay

• ensure ends of split pins are properly spread

• inspect for any other unusual condition v4.0, 21.3.3. Inspection requirements for large plug-in and Q type BRB 930 relays ST Large plug-in and Q type BRB 930 relays shall be periodically inspected for abnormal operation (to the extent practical without removal) in accordance with the signalling technical maintenance plan. However, the period between inspections shall not exceed 52 weeks.

The following inspection criteria for large plug-in and Q type BRB 930 relays shall be included in signalling safeworking procedures:

02000 • inspect for evidence of overheating, such as discoloration or distortion of plastic covers, and burn marks on circuit boards, electronic or electrical components

• ensure plastic covers are not fouling the contact assembly and are not loose, warped or

SC cracked

• inspect for contact burning, or pitting of the carbon contacts

• inspect for evidence of melted solder and other particulates across contacts or base of HR plastic cover

T • inspect for displaced or worn carriers

• inspect for rust on plated components or signs of excessive deterioration of the plating by • ensure retaining clip is securing relay in base

21.3.4. Inspection requirements for time limit relays

Electro-mechanical and thermal type timer relays shall be periodically tested for the correct time-out duration (not exceeding 10% of the specified time) and operation in accordance with the signalling technical maintenance plan. However, the period between inspections shall not exceed two years.

Electronic time limit relays, such as QTD5 or similar may be exempt from periodic testing.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

21.3.5. Replacement requirements for vital signalling relays

The procedure for shelf relay replacement shall be in accordance with the like for like renewal requirements as prescribed in this standard.

Unproved ac vane and dc shelf relays shall be periodically inspected and overhauled in accordance with the signalling technical maintenance plan. However, the period between

04/05/2021 overhaul shall not exceed 15 years, except for relays used on cut-tracks which will not exceed 10 years.

Proved ac vane and dc shelf relays, and other relay types shall be replaced on a needs basis.

Samples of Q type BRB 930 relays in service for 20 years or more shall be inspected from

v4.0, typical installations to assess the need for replacement. The inspection shall eventually cover all such relays in service over a defined period, determined by the assessment process. The operator/maintainer shall have an adequate asset management process in place to address

ST these inspection requirements.

The inspection shall be performed in suitable workshops by persons competent to do so, jointly with licensed signalling personnel. A report of the sample relays inspected shall be compiled and sent to the responsible signal engineer for review and determination.

All vital signalling relays shall be fitted with suitable labelling to identify the relay as overhauled. The label shall include relevant information, such as the date of overhaul, workshop and tester's 02000 identification and any specific values pertaining to the relay type.

21.3.6. Programming the replacement and overhaul of vital signalling

SC relays

The responsible signal engineer shall have an effective program for the replacement and overhaul of vital signalling relays, as required by this standard. The program shall include

HR relevant details of ac vane and dc shelf relays in service. The program shall also include details of ac vane and dc shelf relays that were replaced due to defect or periodic overhaul. T 21.3.7. Treatment of safety related relay faults

by Any vital signalling relay that fails to de-energise, or falsely indicates an energised or de-energised state, or has a fault which can impact the safety of the signalling system shall be immediately protected in accordance with signalling irregularity requirements, as prescribed in this standard. The relay shall not be initially disturbed. The responsible signal engineer shall be promptly advised to provide further instruction. The failure and investigation shall be treated as a signalling irregularity.

Vital signalling relays identified with defects shall be analysed jointly by a signal engineer and a relay manufacturer or overhaul expert in a suitable workshop environment. The pending actions,

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

including the addressing of any potential effects for similar relays in service or spares, shall be promptly attended to and closed-out.

22. Inspection and testing of signals and signs

Signals and signs referenced in this standard are those shown on signalling plans, track plans

04/05/2021 and working sketches. These are viewed by train drivers or by users at level crossings for the purpose of safeworking and operation of the railway.

Signals display either a colour light or semaphoric indication. Signs can be passive, retro reflective or active.

Running signals shall be maintained to display the optimal indication from the lens system and v4.0, the applicable sighting of the indication shall be as long and continuous as practical, with regard to not causing 'read-through'.

ST The focus of signals shall be maintained not to cause an ambiguous or read-through indication.

The door of colour light signals shall not be opened, where the risk of light penetrating through the open lamp case can affect approaching trains (causing an irregular signal indication). Signal doors shall be checked to ensure that they are securely closed and locked before leaving the signal site.

02000 22.1. Requirements for periodic and responsive signal sighting

Signals and signs shall be periodically inspected and maintained for optimum visibility and SC acceptable sighting distance, in accordance with signalling design principles. The frequency of this work shall be in accordance with the signalling technical maintenance plans and whenever the opportunity exists during the course of other site visits.

HR The sighting inspection shall observe for obstructions such as vegetation growth, new or altered structures, as well as changes to the environmental conditions (for example, landscape T background and lighting conditions), whether these conditions are on or off the rail corridor. Any pending actions from such inspections shall be promptly addressed. by In difficult cases where the signal indication cannot be distinguished due to sunlight shining directly onto the lenses, the responsible signal engineer shall be notified to provide an appropriate solution. Any configuration change required in this regard shall be approved by the AEO that provides the design assurance accountability.

For level crossing signals and signs (active and passive types as applicable), similar action is required to ensure that the road and pedestrian users receive good sighting of the level crossing lights and signs. The signal focus and intensity shall be checked as part of periodic maintenance. This will necessitate viewing the signals on all approaches to the level crossing from a suitable distance, in accordance with signalling design principles.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Running signals shall be regularly checked from the driver's cabin by a signal engineer or other competent representative for correct focus, optimum light intensity, sighting obstructions, and the potential for phantom or ambiguous indications. The inspection provides an opportunity to liaise with the driver to obtain their perspective of the signal sighting and shall preferably be done in collaboration with a lead train crew representative.

The signal sighting inspection frequency shall be in accordance with the signalling technical 04/05/2021 maintenance plan. However, the period between inspections shall not exceed 26 weeks on passenger lines and 52 weeks on non-passenger lines.

Where a phantom signal indication is possible, arrangements shall be made to have anti phantom filters fitted to the lens modules concerned. v4.0, The lights displayed by mechanical signals shall be checked at night while colour light signals shall be checked during daylight.

Where a signal sighting committee is formed to review the sighting of a signal due to a SPAD or ST other sighting issue, the committee shall use a signal sighting checklist and compile a signal sighting form. A sample of the checklist and form are available in SPG 0711.

22.2. Maintenance and inspection of signals

Signals shall be periodically inspected to ensure that the whole profile is in accordance with the

02000 specific signalling design and in proper condition. The signal profile includes the following elements:

• signal post, structure and ladder SC • hoods and backgrounds

• lamps or LEDs, lenses and lamp cases

HR • mechanical arms

• identification and notice plates T • termination boxes

The frequency of maintenance and inspection for signals shall be in accordance with the by signalling technical maintenance plan.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

22.2.1. Maintenance of lamp cases, hoods and backgrounds

The coating of lamp case interiors shall be checked to be coloured matt black to minimise reflection of external light.

The matt black coating on hoods and front of backgrounds shall be checked to be in good condition and not capable of reflecting external light. 04/05/2021

22.2.2. Maintenance of lamps

All lamps used in signals shall be of the correct type, voltage, wattage and filament arrangement in accordance with the specific signalling design. v4.0, New lamps shall be kept in their wrapping and stored in a dry place until they are put into service, to prevent any damage or deterioration due to corrosion.

Multi-filament lamps such as SL35 type shall be a good fit in the lamp holder and properly ST seated with the main filament at the focal point of the lens. Multi-filament lamps shall be inserted in the holder so that the main filament is normally illuminated. The lamp shall also be checked that on breaking the main filament circuit, the auxiliary filament becomes illuminated. When replaced, new lamps shall be observed to light up before being left in service.

Signal lamp voltages shall be checked on installation, when replaced or as necessary due to

02000 regular failure.

Lamp voltages shall be measured across the terminals of the lamp holder.

Level crossing lamp voltages shall be measured with the level crossing battery supply operating

SC with the charger turned off.

To maximise lamp life, the lamp voltage shall be adjusted towards the minimum voltage.

Table 1 provides the maximum and minimum voltage settings for signal lamps. HR T by

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Table 1 – Signal lamp settings

Lamp rating Maximum setting (volts) Minimum setting (volts) 10 volt 5 watt 9. 7 9.4 10 volt 11 watt 9. 7 9.4 10 volt 13/3.5 watt 9. 7 9.4

04/05/2021 10 volt 18 watt 9.5 9.0 10 volt 18/3.5 watt 9.5 9.0 10 volt 25 watt 9.7 9.4 (level crossing lights) 12 volt 2/2 watt 10.7 9.0

v4.0, 12 volt 24/24 watt 11.7 / 11.5* 11.3 / 11.1* 12 volt 24/24 watt 10.7 / 11.3+ 10.2 / 11.1+ (subsidiary and marker lights) 12 volt 36 watt 11.2 10.7 ST 12 volt 36 watt 10.1 9.5 (subsidiary lights) 120 volt 15 watt busbar value busbar value 130 volt 60 watt busbar value busbar value * applies to lamps where separate voltage taps are not provided for the main and auxiliary filaments and the auxiliary filament is not subject to voltage drop across the filament changeover relay coils 02000 + applies to lamps in Solid State Interlocking installations

22.2.3. Maintenance of LED modules

SC LED modules used in signals shall be of the correct type, voltage and current in accordance with the specific signalling design.

LED modules shall be appropriately packaged against damage during transportation.

HR LED modules shall display no less than 50% of the applicable individual LEDs contained within the module or otherwise they shall be promptly replaced. T LED modules that display between 50% and 75% of the applicable individual LEDs contained within a module shall be managed for change-out. by Care shall be taken to ensure any replacement LED module is of the correct type by checking the voltage, colour, model and conditioning resistors to be in accordance with the specific signal design.

Whenever a LED module is replaced, or the wiring to a LED module altered, a functional test of the signal shall be performed to ensure that the signal displays the correct aspect and focus. Additionally, the voltage at the LED module shall be checked and an inspection made for any defective LEDs. Where current proving is in force, the current shall be measured and the

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

proving circuit checked for functionality by breaking the circuit to the lit LED module. The light intensity shall be compared with other lights of the same signal.

22.2.4. Maintenance of lenses

Lenses shall be cleaned during periodic maintenance and as necessary. Cleaning products which contain abrasives or solvents shall not be used to clean lenses. 04/05/2021 Lenses shall be inspected to ensure that they are not cracked, damaged or faded, such that they can impair the optimum light intensity or appear as another colour (for example, red appearing as amber).

Where lenses are regularly subjected to graffiti, an acceptable graffiti protective coating may be v4.0, applied.

Whenever lenses are replaced, a functional test of the signal shall be performed to ensure that the signal displays the correct aspect and focus. ST

Where the outer lenses of running incandescent signals are partially or completely missing, the lens shall be either immediately replaced, or otherwise the lens removed or securely covered with dark non-reflective material. Additionally, the lamp shall be removed and the respective controlling relay disconnected.

In such cases, the more restrictive indications of the signal may be left working. For example, if

02000 the full clear (green) indication is missing, then the signal medium and caution indications may be left working. However, if the caution (where caution is the lowest proceed-aspect) or low speed indication is missing, then the signal shall be retained at stop and booked out of use. In

SC any case, the signaller shall be advised of the situation.

22.2.5. Maintenance of mechanical signals

HR The signal operating structure, including its signal wire length and supports shall be periodically inspected to ensure that the signal arm movement is not restricted by corrosion or any obstacle

T which can impact the signal's ability to display a stop indication.

Signal stay wires and associated mechanical items shall be checked to ensure that they remain clear of the structure gauge. by

The back-spectacle shall be adjusted to enable the back-light to be seen only when the signal arm is horizontal.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

22.2.6. Maintenance of signs

Signs shall be inspected periodically in accordance with the signalling technical maintenance plan to ensure that the wording remains in accordance with the signalling design.

Signs shall be cleaned and observed for damage, legibility, colour fade, retro-reflectivity and clear sighting. Where such legibility and retro-reflectivity is significantly diminished, the sign 04/05/2021 shall be replaced.

Where signs are regularly subjected to graffiti, an acceptable graffiti protective coating may be applied.

v4.0, 22.2.7. Signal structural inspection

The structural integrity of posts, mounting brackets and gantries used for signals, warning lights, buffer stop lights, level crossings, guard indicators, signs, and associated equipment shall be

ST periodically inspected in accordance with signalling technical maintenance plans.

The whole structure shall comprise its supporting components, landings, ladders, gateways, walkways, handrails, signal cages, fall-arrest devices and foundations, as applicable.

Examinations beyond the competency of signalling personnel shall be referred to others holding such structural competency. Signalling safeworking procedures shall nominate the responsibility

02000 of inspection requirements accordingly to ensure clear accountability.

Signalling safeworking procedures shall contain a suitable check list to assist inspection personnel when compiling suitable reports where rectification work is necessary. SC 23. Gauging of trainstops

Trainstops provide protection for trains that inadvertently pass signals at stop. In other

HR circumstances, trainstops provide speed checking for approaching trains. The raised position of the trainstop trip arm is paramount for its effectiveness and for this reason trainstops are T gauged to ensure that the raised trip arm position is within specification.

Trainstops may be exempt from periodic gauging. However, trainstop gauging shall be triggered

by by specific events which can cause the trainstop trip arm to become out of gauge.

The following are examples of typical events that can affect the gauge of the trainstop trip arm:

• occurrence of re-railing adjacent to the trainstop

• renewal of the trainstop

• reinstatement following temporary removal of the trainstop such as facilitating trackwork

• renewal or adjustment of the trainstop trip arm

• renewal or adjustment of a trainstop component affecting the height of the trip arm

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• renewal or refastening of the trainstop mounting

• where signs or evidence indicates the trip arm is out of gauge such as non-aligned trip marks on the trip arm face

• where the adjacent track alignment has changed or the rail fixings replaced or adjusted

Whenever trainstops are gauged, an attested return shall be duly submitted to the responsible 04/05/2021 signal engineer.

24. Inspection and testing of points

Points referenced in this standard are the power operated layouts and layouts operated from a v4.0, mechanical frame. Non-interlocked points, including ball lever and throw-over types, or spring switch types such as Thompson, Thornley, or similar, are not covered by this standard.

Point operating mechanisms and layouts shall be periodically maintained, tested and certified to ST ensure that their operation is safe and reliable. The point lock and point detection shall be certified to ensure that they remain within their specified limits. The open-switch shall be checked to be securely held in the correct position. The rear flangeway of open switches shall be checked to have sufficient clearance. The frequency of this certification shall not exceed 30 days, excepting for derailers and specific Spherolock point layouts which shall not exceed 90 days. The periodic certification of points is a safety critical task and shall be treated in

02000 accordance with Section 20.2 of this standard.

Note: The specific requirements for Spherolock points that permit their safety critical task frequency to be extended to 90 days are prescribed in the technical maintenance SC plan.

Before commencing work on points, consideration shall be given to the risks associated with the work, having the potential to impair or disrupt the safe and reliable operation of trains. The

HR arrangement to perform this work shall be in accordance with Section 20.1 of this standard.

T For testing purposes, mechanical points shall be operated by means of the lever in the interlocking machine. Power operated points shall be preferably operated using the manual operation facilities provided, such as EOL or ESML, or the actuator arrangements in air control by units where manual operation facilities are unavailable. Otherwise they can be operated from the usual signalling control.

Note: On some electric point machines, the points may require power-operation upon restoration to ensure that the mechanism has operated to its full stroke.

Where the point-lock locks the points both ways, each switch rail shall be tested.

The closed-switch opening gaps stated in this standard for the purpose of point lock and point detection testing shall be effective, generally between the switch-tip and up to 75 mm from the

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

switch-tip, or otherwise in line with the respective point lock or detector rod as specified by the respective equipment manual.

Signalling safeworking procedures shall prescribe the applicable methodologies for the testing of point lock and point detection that complies with the settings specified in this standard. The methodologies prescribed may include effective novel methods of testing that are in accordance with ASA signalling principles. 04/05/2021

24.1. Objective of point testing

The objective of point testing is to prove the safety critical elements of points are effective and will remain so until at least the next scheduled certification. v4.0, The following safety critical elements are to be proven effective during point testing:

• the closed-switch is closed and locked against the stock rail

ST • the open-switch is securely held in the correct position

• the open-switch rear flangeway has sufficient clearance

• the positions of point switches are correctly detected

• the positions of point drives, lock drives and other critical movements are correctly detected; for example, operating bar, plunger lock, indication box, mechanical point lock

02000 plunger

The closed-switch shall be checked to be closed against the stock rail along its machined length and without switch-roll, having sufficient spring applied where applicable. The open-switch shall SC be checked to be securely connected, such that it remains fully open to the correct specification and provides sufficient rear flangeway clearance. The associated point rodding and fastenings shall be checked to ensure that they are effective and in proper condition. HR 24.2. Prerequisite tasks for point testing T Certain tasks are required to be done as a prerequisite to point lock testing and point detection testing. These are done to confirm the satisfactory condition of the various elements before

by testing for certification.

The following are examples of prerequisite tasks required before point testing:

• checking the layout for excessive movement that can alter the correct track gauge, including any excessive lateral movement of switch and stock rails

• checking the stock and switch rail conditions for rail overflow and evident rail defects (including rail surface defects) that can affect the integrity of the turnout

• checking the point lock, detection and drive components to ensure that they are secure, are in sound condition and will effectively perform the intended function

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• cleaning and lubricating, as applicable, the switch plates and switch rollers (where fitted) to remove contaminants and permit uninhibited operation of the switch rails

• checking the switch plates or rollers for even loading from switch rails

• checking the back-drive equipment (where fitted) for correct and smooth operation

04/05/2021 24.3. Requirements for point lock testing mechanically operated points

Mechanically operated points shall be tested to ensure that the closed-switch cannot open by 3.2 mm or more. This requirement shall be reliant on achieving the following conditions:

v4.0, • completion of the prerequisite tasks described in Section 24.2 of this standard

• the point switches lying in correct position

• the point lock has fully entered ST

The point lock shall not enter if the closed-switch is open by 3.2 mm or more.

For reliability, the point lock shall be adjusted to fully enter with a closed-switch opening of at least 1.6 mm.

Each open-switch shall be checked to be securely held in the correct position.

02000 The rear flangeway clearance of each open-switch shall be checked to have sufficient clearance. Any event causing the rear flangeway clearance to become altered (for example, worn switch rail, loose back-drive nuts, bent rodding) shall be suitably tested to ensure that the clearance is in accordance with the specification. SC

The point lock plunger travel shall be 200 mm, except in cases where double lock plungers are worked by one lever, the travel shall be 175 mm. When the lock plunger is withdrawn, the clearance between the end of the lock plunger and the slotted lock rod or the locking rod block HR shall be 20 mm. T 24.3.1. Other requirements for mechanically operated points

On mechanically operated catchpoints, a fully entered point lock shall not permit the by open-switch to close by less than 100 mm. Additionally, the point lock shall not enter if the open-switch is open by less than 100 mm.

On mechanically operated points fitted with a wide cut notch point lock for the trailing only switch, the point lock specification may be exceeded. In this case a fully entered point lock shall not permit the closed-switch to open by 6.4 mm or more. Additionally, the point lock shall not enter if the closed-switch is open by 6.4 mm or more. Refer Section 24.6.2 of this standard for requirements that relate to the provision of wide cut notch point locks.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

On mechanically operated points fitted with point lock detectors (such as HLM style); the point lock shall enter into the slide notch with sufficient clearance on both sides. The point lock shall not enter with a closed-switch opening of 3.2 mm or more. However, the point lock shall fully enter with a closed-switch opening of 1.6 mm or less. Where a wider notch is used in point lock detectors as a replacement for wire locks (such as at Lithgow), the point lock settings may be altered so that the point lock does not enter with a closed-switch opening of 4.8 mm or more

04/05/2021 and fully enters with a closed-switch opening of 3.2 mm or less.

24.4. Requirements for point lock testing power operated points

v4.0, Power operated points shall be tested to ensure that the closed-switch cannot open by 3.2 mm or more. This requirement shall be reliant on achieving the following conditions:

• completion of the prerequisite tasks described in Section 24.2 ST • point switches lying in correct position

• point lock has fully entered

The point lock shall not enter if the closed-switch is open by 3.2 mm or more.

For reliability, the point lock shall be adjusted to fully enter with a closed-switch opening of at least 1.6 mm. 02000 Each open-switch shall be checked to be securely held in the correct position.

The rear flangeway clearance of each open-switch shall be checked to have sufficient

SC clearance. Any event causing the rear flangeway clearance to become altered (for example, worn switch rail, loose back-drive nuts, bent rodding) shall be suitably tested to ensure the clearance is in accordance with the specification.

HR 24.4.1. Requirements for Claw Lock points

T On Claw Lock points, the point lock specification may be exceeded such that a fully entered point lock shall not permit the closed-switch to open by 4.8 mm or more. Additionally, the point lock shall not enter if the closed-switch is open by 4.8 mm or more. by For reliability, the point lock shall be adjusted to fully enter with a closed-switch opening of at least 3.2 mm.

24.4.2. Requirements for EP swing nose points

A swing nose crossing where operated by a Claw Lock electro-pneumatic mechanism fitted with HLM point lock detector, shall lock the Claw Lock operating bar at the extremities of its 180 mm travel. The HLM lock shall enter each notch centrally with equal clearance on both sides.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

24.4.3. Other requirements for power operated points

On power operated catchpoints, a fully entered point lock shall not permit the open-switch to close by less than 100 mm. Additionally, the point lock shall not enter if the open-switch is open by less than 100 mm.

On power operated points fitted with a wide cut notch point lock for the trailing-only switch, the

04/05/2021 point lock specification may be exceeded such that a fully entered point lock shall not permit the closed-switch to open by 6.4 mm or more. Additionally, the point lock shall not enter if the closed-switch is open by 6.4 mm or more. Refer Section 24.6.2 of this standard for requirements that relate to the provision of wide cut notch point locks. v4.0, 24.5. Requirements for point detection testing

Upon completion of the prerequisite tasks described in Section 24.2 of this standard, and with the point switches in their correct position, the point detector contacts shall be tested for the ST following:

• to be opened with a closed-switch opening of 4.8 mm or more

• to be closed when the closed-switch opening is 3.2 mm or less

• to be opened when the open-switch opening is less than 95 mm

02000 Note: The open-switch detection is certified during initial points set-up and whenever components that affect the detection of the open-switch are replaced or adjusted.

Subsequently, whenever periodic inspection of detection components, such as

SC detector rods, linkages and their fastenings is performed, that ensure the correct operation of the open-switch, then this will satisfy the open-switch detection requirement.

HR Point detector contacts shall be visibly observed or otherwise checked using a voltmeter.

T 24.5.1. Requirements for detection testing mechanisms where detection is interlocked with point lock

by On some point mechanisms, the point detection is interlocked with the point lock, such that the point lock is required to enter before enabling the detector contacts to close.

In these cases the point detection setting shall be correct, such that the detection contacts will open and close in accordance with the specifications prescribed in this standard.

Accordingly, the periodic certification of the point detector shall be done for mechanisms that provide visual sighting of the detector actuator roller and also for mechanisms that do not provide visual sighting of the detector actuator roller.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

For mechanisms that provide visual sighting of the detector actuator roller, the following requirements shall be complied with:

• The point detection settings shall be assured by checking the proximity of the detector actuator roller relative to the detector slide notch, such that the relevant contacts open and close in accordance with the go/no-go specifications prescribed in this standard. This test may be achieved without the need to slacken (float) the point lock. 04/05/2021

• The point detector contacts shall be checked to be open while the point lock is tested at the no-go specification.

For mechanisms that do not provide visual sighting of the detector actuator roller, the following requirements shall be complied with: v4.0, • The point lock shall be accordingly slackened (floated) to allow the lock to enter. This provides the opportunity to check the point detection settings.

ST • The point detector contacts shall be checked to be in accordance with the go/no-go specifications prescribed in this standard.

• The point lock shall then be readjusted and certified in accordance with the go/no-go specifications prescribed in this standard.

Other methodologies that assure the correct detection of point switches in these circumstances

02000 can be applied; however, the methodologies used shall be in accordance with ASA signalling principles.

24.5.2. Requirements for testing point operating bar detection on Claw SC Lock and Spherolock points

Point operating bar detection (also known as point lock coverage detection) on Claw Lock and Spherolock points is tested to ensure that adequate point lock coverage is achieved, at the HR moment the detection of the point operating bar is just made.

T Point operating bar detection is tested and certified during the initial set-up of points when commissioned.

Point operating bar detection shall be subsequently tested and certified whenever an event, by such as a setting or component change has affected (altered) any of the following:

• position of the open-switch

• detection of the open-switch

• detection of the operating bar, where separate detectors are used

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The subsequent testing of point operating bar detection during normal train running can be impractical and as such, periodic testing of point operating bar detection may be exempt where the aforementioned events have not occurred to alter the settings.

This is based on the following reasons:

• the point operating bar detection is a relatively coarse setting

04/05/2021 • the detection contacts are back-proved in the circuit design and thus the operation is checked from one position to the other

• the causes for out-of-adjustment situations are mitigated by maintenance tasks and event driven tasks v4.0, Point operating bar detection methods and specifications

The method and specification for testing point operating bar detection is different depending on

ST the type of arrangement in use.

Following are the specified minimum dimensions for the different arrangements in use that prove the position of the operating bar and thus ensure that adequate point lock coverage is achieved:

• Electro-pneumatic Claw Lock and Spherolock points using the open-switch detector contacts 02000

A minimum of 20 mm point lock coverage shall be provided whenever the open-switch detector contacts are made for normal or reverse positions.

SC • Electro-pneumatic Claw Lock and Spherolock catchpoints or independent switches using a separate detector (for example, U5A or HM) fitted at the end of the operating bar

A minimum of 30 mm point lock coverage shall be provided whenever the operating bar

HR detector contacts are made for the closed-switch.

• Electro-pneumatic Claw Lock points, including catchpoints using separate micro switches T fitted at the motor/operating bar

A minimum of 30 mm point lock coverage shall be provided whenever the motor/operating by bar micro-switch contacts are made for normal or reverse positions, or the closed-switch for catchpoints.

• Electric Claw Lock and Spherolock points, including catchpoints and independent switches using the operating bar detector contacts incorporated within the point mechanism (for example, Siemens 84M)

A minimum of 20 mm point lock coverage shall be provided whenever the operating bar detector contacts are made for normal or reverse positions, or the closed-switch for catchpoints and independent switches.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

It can be impractical to achieve the specified dimensions for swing nose points and are therefore exempted from these requirements. However, the maximum achievable point lock coverage shall be afforded to swing nose points.

24.5.3. Requirements for detection testing point locking mechanisms on mechanical points 04/05/2021 Mechanical facing points fitted with a type D point lock are provided with a cross-slide or detection slide. The slides are operated by the point lock plunger and are connected to an electrical or a mechanical detector. The detector proves the locked position of the type D point lock.

v4.0, The detector contacts shall not make until the point lock plunger has completed two thirds of its stroke. This specification equates to a dimension between 130 mm and 140 mm of its 200 mm stroke towards the locked position.

ST Detection of mechanical facing points fitted with a HDLM type point lock is achieved internally within the HDLM unit by two changeover contacts. The lock bar has slots machined on each side which the lock bolt will drop into when the lock bar slides to the locked position. The locked position is detected by cut-outs on the detector slides via bell cranks and rollers.

The detector contacts shall prove the lock position of the HDLM point lock. The detector contacts shall not make until the point lock bolt has dropped into the locked position. 02000

24.5.4. Requirements for detection testing EP swing nose crossings

The point detection settings of EP swing nose crossings for the switch position are the same as SC that of other points.

Where HLM point lock detectors are used to lock the swing nose crossing, the detector contacts shall prove the lock position of the HLM point lock. The detector contacts shall not make until HR the point lock bolt has dropped into the locked position. T 24.5.5. Requirements for detection testing derailers

The detector shall prove the position of the derailer; for example, derail position and clear by position.

Derailer detector contacts shall be made to close when the derailer is in a position to effectively derail a train. The same contacts shall be made to open when the derailer is not in an effective derail position.

Where contacts are used to also prove the derailer in a clear and safe position for the passage of a train, the associated contacts shall only make when the derailer is in the fully cleared position. Similarly, the same contacts shall be open when the derailer is not in the fully cleared position.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The detector contact settings may be adjusted slightly coarse because of the latitude between the effective derail position and the fully cleared position.

24.5.6. Requirements for detection testing point back-drives

The detector contacts of back-drive detectors (where fitted) shall be opened at approximately 6.4 mm for the closed-switch opening. This is measured at the back-drive detector. The detector 04/05/2021 contacts shall be closed with a switch opening of 4.8 mm or less.

24.6. Provision for lock slide removal and wide cut notch point lock v4.0, The provision to remove lock slides from point machines applies only to the points that are trailing-only in both directions and operated by combined electric switch machines.

The provision to allow a wide cut notch in a point lock applies only to the following ST configurations:

• open-switch catchpoints operated by combined electric switch machines

• open-switch catchpoints operated by signal branch electro-pneumatic or mechanical mechanisms

• trailing-only position of points operated by signal branch electro-pneumatic or mechanical 02000 mechanisms

24.6.1. Providing approval for lock slide removal and wide cut notch

SC point lock

Where the reliability of trailing-only points can be improved by the removal of point lock slides or by the provision of a wide cut notch point lock, then it is permissible to implement such

HR arrangement in accordance with signalling design principles.

The responsible signal engineer shall approve these provisions and control a register of all T points with point lock-slides removed or with a wide cut notch point lock.

Points fitted with wide cut notch point lock slides shall be inspected every two years by a signal by engineer as part of their mechanical interlocking inspection to ensure that the integrity of the arrangement is maintained and that the inscriptions remain in accordance with the signalling plan or working sketch.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

24.6.2. Requirements for lock slide removal and wide cut notch point lock

Signalling safeworking procedures shall include the following requirements for the removal of point lock slides in points operated by combined electric switch machines:

• the unused guide-ways on both sides of the machine are plugged to prevent entry of dust 04/05/2021 and grit

• the points shall be identified as non-locked points to network operators, for the purpose of yard working

• the affected point-end shall be identified in the signalling plan or working sketch as having v4.0, lock slides removed

Signalling safeworking procedures shall include the following requirements for the provision of a wide cut notch point lock for the open-switch catchpoint of points operated by combined electric ST switch machines:

• the wide cut notch point lock shall be machined at an engineering machine shop

• the allowable cut out for the wide cut notch in the point lock shall not exceed 13 mm wider than the respective locking dog

• the point lock slide shall be stamped with the words 'wide cut notch' together with the 02000 applicable point end number, all in 6 mm letters

• the stamped text shall be adjacent to the wide cut notch on one side of the lock slide, and

SC on the top and bottom face at the end between the elongated slot and second hole

• an additional set of lines shall be inscribed on the opposite face corresponding to the new wide cut notch point lock, and the old marks shall be stamped with a cross

HR • installation of wide cut notch point lock-slides shall be certified by a signal engineer

• T the affected point-end and open-switch position shall be identified in the signalling plan or working sketch as having a wide cut notch point lock

• the lock slide with a wide cut notch shall always belong to its respective point end at the by specified location, or otherwise when made redundant shall be destroyed

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Signalling safeworking procedures shall include the following requirements for the provision of a wide cut notch point lock for the open-switch catchpoint or the trailing-only position of points operated by signal branch electro-pneumatic or mechanical mechanisms:

• the allowable cut-out for the wide cut notch in the point lock shall not exceed 13 mm wider than the respective locking dog

04/05/2021 • installation of wide cut notch point lock-slides shall be certified by a signal engineer

• the trailing-only position of points shall be identified as non-locked points to network operators for the purpose of yard working

• the affected point-end and open-switch/trailing-only position shall be identified in the

v4.0, signalling plan or working sketch as having a wide cut notch point lock

• the lock slide with a wide cut notch shall always belong to its respective point end at the specified location, or otherwise when made redundant shall be destroyed ST 24.7. Provision to extend point detection limits

On trailing-only points, signalling safeworking procedures may permit an increase to the detection setting for reliability reasons to extend the detection limit of the closed-switch opening from 4.8 mm to 6.4 mm.

02000 This arrangement shall be conditional upon all of the following requirements:

• there is no signalled move through the trailing points in the facing direction

• there is no reversing move where part of the train would set back through the points in a SC facing direction

• the arrangement is duly updated on the relevant signalling plan or working sketch

• a register of the arrangement is controlled by the responsible signal engineer HR

T 25. Inspection and testing of track circuits

Track circuits provide a means of rail vehicle detection as utilised by the signalling system. by Track circuits require inspection, testing and maintenance, periodically and sporadically; for example, following planned works such as re-railing, or unplanned events such as responding to failures. The safety critical and safety significant tasks prescribed in this standard shall not be exceeded. Additionally, signalling personnel shall be vigilant for evidence of potential track circuit problems whenever the opportunity permits.

Any condition found with the potential to cause a track circuit to incorrectly indicate an unoccupied state shall be treated as a signalling irregularity and the responsible signal engineer be promptly notified.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Any condition found with the potential to reduce the reliability of a track circuit shall be actioned in accordance with the operator/maintainer requirements, and network rules and network procedures.

25.1. Objective of track circuit inspection, testing and maintenance 04/05/2021 The objective of track circuit inspection, testing and maintenance is to find and remove any potential failure condition, and ensure as far as practicable that the track circuit will function safely and reliably. The track circuit shall comprise all the necessary components required to enable its safe and reliable operation. v4.0, The following are examples of track circuit components:

• track circuit power supplies

ST • transmitter/feed units

• receiver/processer units

• trackside units and interfaces

• track circuit resistor and capacitor units

• track circuit relays 02000 • rail surface, track and ballast condition

• impedance bonds

SC • insulated rail joints

• equipment wiring, track wiring and cabling

• traction bonds and parallel bonds HR

• wiring connections, including rail connections T • lightning protection

The following are examples of specific tasks that pertain to track circuits: by • performing inspection and maintenance of track circuit components

• recording of power supply and track circuit voltages, currents and settings

• performing shunt tests, including train shunt test where applicable

• performing polarity tests, where applicable

• performing zero feed tests

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Track circuits that fail safety testing criteria shall be immediately reported to the responsible signal engineer or other relevant signal engineer. In the absence of prompt, effective remedial action, the protecting signals shall be booked out of use. Track circuits shall not be left operating in an unsafe condition.

25.2. Track circuit records 04/05/2021 Track circuit records (for example, track circuit history cards) shall be used to record observations, test values, adjustments and events that pertain to the track circuit. The records provide a means of detecting trends. Gradual consistent variations can indicate the imminent deterioration of a track circuit component. These variations shall be identified and resolved. v4.0, Track circuit records shall be made available at the receiver/relay location of the track circuit. The relevant tests and information shall be recorded thereon. The most recent track circuit record shall indicate the first and last full details of any previous record used. This provides a

ST long term baseline to compare variations.

A separate track circuit record shall be used for each track circuit and also for the following applications:

• pin-point detectors (DPU)

• centre-fed track circuits 02000 • common transmitter track circuits

• two receiver track circuits

SC • cut track circuits

• master and slave ends of Microtrax coded track circuits

• overlay track circuits HR 25.3. Track circuit inspection and tests T

The track circuit tests prescribed in this standard shall be performed as necessary during periodic maintenance. Examples of other events that require track circuit testing include the by following:

• in response to an associated failure or incident

• following re-railing or trackwork

• following periods of track disuse

• whenever track circuit components are interfered with or replaced

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

25.3.1. Drop shunt test

A drop shunt test proves the resistance value of the track circuit shunting characteristic. The drop shunt resistance is measured using a variable shunt device called a shunt box. The drop shunt value shall be the highest value of resistance that is obtained when the shunt box is placed across the rails, which causes the track circuit relay/output to drop away.

04/05/2021 When taking the drop shunt measurement, the leads of the shunt box shall be connected across the rails at the relay/receiver end of the track, set at a high value at which the relay/output is energised. The resistance is then decreased until the track circuit relay/output drops away. At that point, the drop shunt value is then measured. The drop shunt test shall be repeated three times until consistent results are obtained. This result is recorded on the track circuit record. v4.0, The drop shunt value shall be in accordance with the specific track circuit equipment manual. However, the drop shunt resistance value shall not be less than the value specified in Table 2 for the relevant track circuit type. ST

25.3.2. Fixed shunt test

A fixed shunt test proves the track circuit shunting characteristic is within the specified limit. A fixed shunt test shall be carried out by connecting a resistive shunt across the rails while observing that the track circuit relay/output drops away with the shunt applied. The shunt

02000 resistor shall be connected across the rails at all extremities of the track circuit (including within crossovers) and at the mid-point of the track circuit. At each point, the track circuit relay/output shall be observed to drop away.

SC The value of the resistive shunt used for this test shall be in accordance with the specified resistance for the relevant track circuit type specified in Table 2.

25.3.3. Fixed shunt check HR The fixed shunt check proves that the track circuit will shunt at a given point along the track,

T usually at the receiver/relay end. The shunt check is done by using a fixed shunt resistor while observing that the track circuit relay/output drops away with the shunt applied.

The value of the resistive shunt used for this test shall be in accordance with the specified by resistance for the relevant track circuit type.

Table 2 provides the minimum shunt resistance for different track circuit types.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Table 2 – Minimum shunt resistance

Track circuit type Minimum shunt resistance DC track circuit with 4 ohm shelf relay 0.15 ohms

DC track circuit with 4 ohm BT1B relay 0.25 ohms

DC track circuit with 4 ohm QT1 relay 0.25 ohms 04/05/2021 DC track circuit with 4 ohm QTM1 relay 0.25 ohms

DC track circuit with 9 ohm QT1 relay 0.50 ohms

DC track circuit with 9 ohm QTA1 relay 0.50 ohms v4.0, HVI Jeumont Schneider track circuit 0.25 ohms – double rail with one BRTCA2 Rx HVI Jeumont Schneider track circuit 0.50 ohms – double rail with one RVT600 Rx ST HVI Jeumont Schneider track circuit 0.25 ohms – double rail with two RVT600 Rx HVI Jeumont Schneider track circuit 0.50 ohms – single rail with Normal/TV-TH1 HVI Jeumont Schneider track circuit 0.25 ohms – single rail with TV-THD2 or TV-LV 02000 AC Signal Branch resistor fed track circuit 0.25 ohms – single rail AC WB&S track resistor fed track circuit 0.50 ohms

SC – single rail AC track circuit with resonant impedance bond 0.25 ohms

AC AAR Standards track circuit 0.06 ohms – double rail HR UM71 CSEE audio frequency track circuit 0.15 ohms

T TI21 ML audio frequency track circuit 0.15 ohms

ET 200 audio frequency track circuit 0.15 ohms by WB&S FS2500 audio frequency track circuit 0.15 ohms

WB&S FS2600 track circuit 0.50 ohms

USS Microtrax coded track circuit 0.25 ohms

Safetran PSO 4000 audio frequency overlay track 0.15 ohms circuit

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

25.3.4. Train shunt check

A final test of the proper operation of a track circuit is the train shunt check. This test is performed to prove that there is effective wheel to rail contact and that a train is effectively detected during its entire passage over the track circuit. A train shunt check shall be required whenever there is doubt about the conductivity of the wheel to rail contact surfaces; for

04/05/2021 example, after re-railing or after an extended period of disuse.

The train shunt check is carried out by monitoring the track circuit relay/receiver input voltage while a train passes over the whole length of the track circuit. The input voltage is observed to ensure it does not exceed the maximum train shunt value in accordance with the relevant values specified in Table 3. v4.0, 25.3.5. Polarity test

A polarity test is performed to prove the polarities across insulated rail joints of like track circuits ST conform to the polarity shown on the specific track insulation plan. In most cases, the polarity of rail voltages across insulated rail joints will be opposite. This requirement avoids an unsafe condition arising, caused by a track circuit being fed from an adjacent track circuit in the event of an insulated rail joint becoming short circuit.

The existence of like polarities is only acceptable at a track feed to track feed interface, or

02000 where a short circuit insulated rail joint would result in both adjacent track circuits becoming de-energised. Polarity reversal does not apply to audio frequency track circuits.

A polarity test is conducted by checking the rail voltage polarities to ensure that the polarity

SC across all insulated rail joints between adjacent like track circuits conform to the specific track insulation plan.

Following are examples of adjacent track circuits affected by like polarity:

HR • dc track circuit adjacent to dc track circuit

•

T 50 Hz ac track circuit adjacent to 50 Hz ac track circuit

• high voltage impulse (HVI) track circuit adjacent to HVI track circuit

by • Microtrax coded track circuit adjacent to Microtrax coded track circuit

The responsible signal engineer shall be advised of incorrect polarities between track circuits as soon as possible. Where incorrect polarities are evident, the condition of insulated rail joints shall be checked to ensure that they are not liable to breakdown before the situation is corrected. Any track insulation reconfiguration shall first require an approved signalling design.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

25.3.6. Zero feed test

A zero feed test is performed to prove that the track circuit relay or receiver is not fed from any other source other than its own track feed or transmitter. Zero feed tests require the track circuit feed or transmitter power supply to be temporarily disconnected. During this time, the relay voltage or receiver input is measured to be near zero and shall not exceed the maximum zero

04/05/2021 feed values specified in Table 3. The track circuit relay/output shall also be observed to have de-energised.

Any track circuit that exceeds the maximum train shunt or zero feed value shall be disconnected and the protecting signalling booked out of use.

v4.0, Notwithstanding the specified maximum zero feed value, test readings above 10% of the drop away test value or above one third of the other values specified in Table 3 shall be investigated and immediately reported to the responsible signal engineer.

ST Note 1: The drop away test value for shelf relays is the drop away value shown on the manufacturer's or workshop's test label on the relay. The drop away test value for plug-in relays is the standard drop away value for that type of relay.

Note 2: On ac vane relays, the supply to the local coil needs to be first opened before conducting the test. On audio frequency track circuits, the transmitter for the track adjacent to the receiver needs to have the supply fuse removed unless a frequency 02000 selective voltmeter is utilised.

Note 3: Where a rail vehicle is fitted with a track circuit actuator (TCA), used to enhance the wheel to rail shunt capability, the vehicle cannot be used for a train shunt SC check unless the TCA is first turned off.

Table 3 provides the maximum train shunt and zero feed resistance values for different track circuit types. It also provides the threshold that requires advising the responsible signal HR engineer.

T Table 3 – Maximum train shunt and zero feed values

Track circuit Test point Unit of Maximum train Advise responsible type measure shunt or zero signal engineer by feed value (see note 1) DC with shelf relay coil V dc <30% of drop >10% of drop away relay away test value test value DC with plug--in R1/R2 V dc <30% of drop >10% of drop away relay away test value test value 50 Hz ac control V ac <30% of drop >10% of drop away terminals away test value test value UM 71 CSEE receiver R1 R2 mV ac <90 >30 (with filter)

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Track circuit Test point Unit of Maximum train Advise responsible type measure shunt or zero signal engineer feed value (see note 1) ML TI 21 input resistor mV ac (mV x gain) <100 (mV x gain) >35 (1 ohm) (with filter) terminals

04/05/2021 ET 200 Receiver mV ac <50% of threshold >30% of threshold TP1 & IP1. (with filter) current current WB&S FS2500 receiver monitor mV ac <400 >135 (with filter) HVI receiver V dc <100 >35 Jeumont terminals (with integrator) v4.0, Schneider HVI C+/C1 V dc <100 >35 Jeumont (RVT-600) 3/C1 (with Schneider (BRT-CA2) integrator) ST USS Microtrax slave end mV dc <80mV (pulse) >50mV (pulse) coded track – track interface circuit panel terminals WB&S FS2600 receiver monitor mV ac <500 >100

Safetran PSO signal display receiver <40 (train shunt) >20 4000 audio signal <20 (zero feed) frequency level 02000 overlay

25.3.7. Inspection of traction bonding

SC Traction bonding includes parallel bonds between rails, tie-in bonds, cross bonds (for example, rail to rail and rail to impedance bond), and traction bonds from rails to substation or section hut busbars. Traction bonding, including its associated connections shall be inspected to ensure it is in good condition. HR

Any open circuit traction bonds or high resistance connections found shall be promptly rectified T or replaced.

Traction bonding not associated with track circuits shall also be inspected to ensure that it is in

by good condition and the connections are not disconnected or damaged. This is done to prevent (so far as is reasonably practicable) the potential for unsafe voltages that can develop across rail breaks or cable breaks. Traction bonding not associated with track circuits is particularly relevant in yards, rolling stock maintenance centres and at end of line sections.

25.3.8. Inspection of parallel bonds

Parallel bonds on track circuits extending over points to a clearance point on another line, shall be inspected along their entire length to ensure the bonding has not been damaged or removed by trackwork, vandals, or other causes. This can result in loss of train detection.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Any open circuit parallel bond or high resistance connection found shall be immediately rectified or replaced.

25.3.9. Inspection of track circuit relays

Track circuit relays shall be inspected in accordance with Section 21 of this standard.

04/05/2021 25.4. Track circuit precautions

Track circuit precautions for the following tasks shall be prescribed in signalling safeworking procedures:

• adjustments v4.0, • circulating currents affecting 50 Hz ac track circuits

• polarity of power supplies ST • interference or repairs to track circuit wires

• contaminated rails

• UM71 CSEE and HVI Jeumont Schneider receiver rack position

• Microtrax coded track circuits

02000 • audio frequency overlay track circuits

These are stated in detail in Section 25.4.1 through to Section 25.4.8.

SC 25.4.1. Adjustments

Track circuit feed voltages shall not be increased to compensate for open circuit or high resistance bonding. In electrified areas, high track feed voltages can increase the probability of

HR circulating currents through traction tie-in bonding or earth paths.

Track circuits adjusted in wet or poor ballast conditions shall be retested when the track has T dried out and the ballast conditions improved to ensure correct shunting of the track circuit.

Licensed signalling personnel are permitted to make minor adjustments. However the by responsible signal engineer shall be accordingly notified.

Intended large adjustments, or adjustments required for unaccountable reasons shall be immediately referred to the responsible signal engineer or other relevant signal engineer for instruction. Large adjustments shall not be made without the authorisation of a relevant signal engineer.

Following any track circuit adjustment, a fixed shunt test (for minor adjustments), or drop shunt test (for large adjustments) shall be performed. A record of the values and reason for the adjustment shall be made on the track circuit record. Additionally, the track circuit shall be

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

monitored accordingly and readjusted immediately when the conditions improve. The responsible signal engineer shall ensure the timely reinstatement of any adjustment.

25.4.2. Circulating currents affecting 50 Hz ac track circuits

Fault conditions with 50 Hz ac track circuits can enable currents to circulate via traction tie-in bonds, earth paths, and so on through other track circuits which can pose a potentially unsafe 04/05/2021 condition. Where unbalanced ac rail currents are detected, the responsible signal engineer shall be promptly notified and the cause of the imbalance investigated and rectified without delay. Open circuit or high resistance rail bonds, series bonds, impedance bond side leads, and their connections, shall be rectified promptly. Jumper bonds, in good condition and installed correctly may be utilised in an emergency. However these will be replaced by permanent bonds as soon v4.0, as possible.

The rail current balance shall be determined by measuring the signalling current in both rails, at

ST both the feed and relay ends of the track, using an induction meter set at 50 Hz frequency. For double rail 50 Hz ac track circuits, an imbalance of rail current greater than 0.5 amps shall be considered significant. For single rail 50 Hz ac track circuits, an imbalance of rail current greater than 1.25 amps shall be considered significant. The currents measured in each cable of a side lead pair should be within 10% of each other. Uneven current sharing indicates a high resistance side lead or connection. The voltage drop across a side lead connection to the rail

02000 should be less than 10 mV ac.

Note: While it is not expected to experience stray 50 Hz ac currents emanating from balanced double rail 50 Hz ac track circuits, this may not be the case with single rail

SC 50 Hz ac track circuits. This is because the traction rails of parallel single rail track circuits are generally connected by tie-in bonds. This provides an alternative low resistance path for the stray currents. Therefore it is not unusual to measure unbalanced 50 Hz ac currents in single rail 50 Hz ac track circuits. HR

25.4.3. Polarity of power supplies T

Whenever power supplies or their associated wiring are worked on, there is a risk that the polarity of 50 Hz ac track circuits can become swapped, potentially causing an unsafe condition. by This is also true when the supply phasing is altered by supply authorities or the location normal or emergency power supply changes state.

Adjacent 50 Hz ac track circuits, fed from different power supplies are mostly at risk. Consequently, the polarities of these adjacent track circuits shall be tested whenever an at-risk event occurs at the power supply level.

Where feed and relay ends of the same 50 Hz ac track circuit are fed from different power supplies, these track circuits shall be promptly reconfigured so that they become fed from the same power supply.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

25.4.4. Interference or repairs to track circuit wires

A fixed shunt check or train shunt check shall be performed whenever two or more track circuit wires to or from the track circuit equipment are disconnected and reconnected. A polarity test between the affected track circuit and adjacent track circuits shall also be performed, where applicable. 04/05/2021 25.4.5. Contaminated rails

Rust and other contaminants that form on the rail surface can affect the wheel to rail interface, potentially causing an ineffective track shunt. Where the rail surface condition is in doubt, a train shunt check shall be performed. Track circuits that fail to provide an effective track shunt shall v4.0, be treated as seldom used apparatus in accordance with Section 16 of this standard.

Similarly, track circuits that are prone to excessive sanding shall be treated as seldom used apparatus. ST

25.4.6. UM71 CSEE and HVI Jeumont Schneider receiver rack position

The task of plugging UM71 CSEE and HVI Jeumont Schneider track circuit receivers into their correct rack positions is critical. The misalignment of a receiver by one module space can have unsafe consequences, resulting in the permanent energisation of the track circuit relay.

02000 These units shall be checked to be in their correct position whenever they are plugged into their base. Additionally a check shall be made to ensure that every vacant module position above and below these units is fitted with obturation fittings and coding plugs. SC 25.4.7. Microtrax coded track circuits

The Microtrax card file shall be securely mounted with all plug-in modules fully inserted and the front panel holding down screws securely tightened. HR

Vacant positions on the cardfile shall have cover plates fitted at all times. T The boards, modules or vital power failure relay shall not be removed or replaced with the Microtrax unit powered up. by Wiring from the Microtrax unit to the track interface panel should not be short-circuited or open-circuited while the Microtrax unit is in operation. The Microtrax unit shall be turned OFF at both ends before interfering with this wiring. Failure in doing so will place the Microtrax unit in selective shut down mode.

When performing shunt tests, the slave-end unit condition shall be monitored. The slave-end unit shall indicate its de-energised state by displaying '0000' in the 'TRK MARGIN' display. To ensure that the occupancy indication displayed remains constant, the track shunt shall be applied for at least 30 seconds.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Microtrax operator keys for crossing loops may be issued to licensed signalling personnel for the purpose of engineering work only, and not for operational use. Where the keys are issued to licensed signalling personnel, the keys shall be numbered and issued to the person who shall be accountable for the security of the key. The key shall not be lent to other persons unless the transfer is approved and documented by the responsible signal engineer.

Microtrax diagnostic and configuration software shall not be copied onto third party machines or 04/05/2021 supplied to unauthorised persons. Under no circumstances shall the vital erasable programmable read-only memory (EPROM) be duplicated or altered by field personnel.

The configuration of modules including associated EPROM shall be permitted only by the AEO that provides the design assurance accountability. v4.0, The storage of Microtrax configuration data (for example, EPROM) and version information shall be registered and kept secure. This shall be managed by the AEO that provides the accountability for maintenance of signalling design records and data. ST Note: A zero feed test is not required for Microtrax coded track circuits.

25.4.8. Audio frequency overlay track circuits (PSO 4000)

The Safetran PSO 4000 audio frequency overlay track circuit receiver indicates its de-energised state by the 'Rx-Int' led in the receiver occupancy display being extinguished. This shall be

02000 monitored in conjunction with the signal display level on the receiver which indicates its de-energised state by displaying a number less than '100'.

The track circuit relay shall also be observed to be in a de-energised state during this time. SC 25.5. Safety critical and safety significant track circuit tasks

The safety critical and safety significant tasks for track circuits are mandatory and shall be

HR treated in accordance with Section 20.2 of this standard.

T 25.5.1. Safety critical tasks for double rail 50 Hz ac track circuits

Double rail 50 Hz ac track circuits in electrified areas shall be periodically tested and certified for

by unbalanced rail currents and voltage drop across connections to ensure their safe operation. The frequency of this certification shall not exceed 30 days.

The values of these tests shall be documented on a track circuit record specific for this purpose.

The following tasks shall be included in signalling safeworking procedures for the testing and certification of double rail 50 Hz ac track circuits:

• test track circuit relay coil voltage when unoccupied

• test current in each rail for balance at relay end

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• test current in each rail for balance at feed end

• test current in each cable of impedance bond side lead for balance at up rail

• test current in each cable of impedance bond side lead for balance at down rail

25.5.2. Safety significant tasks for track circuits installed with parallel

04/05/2021 bonds

Parallel bonds shall be periodically inspected for continuity and integrity. The frequency of this inspection shall not exceed three months, except where parallel bonds are surface run, have hypalon insulation and have welded rail connections. In this case, the inspection frequency can be extended to six month intervals. In any case, signalling personnel shall take every v4.0, opportunity to inspect parallel bonds whenever opportunities arise; for example, when working in the vicinity of points.

The results of this inspection shall be recorded on the track circuit record. ST

The following tasks shall be included in signalling safeworking procedures for the testing and certification of parallel bonds:

• inspect parallel bonds for electrical continuity in accordance with track insulation plan

• inspect parallel bonds for effective rail connection

02000 • inspect parallel bonds for sound condition

25.5.3. Safety significant tasks for dc track circuits

SC DC track circuits shall be periodically tested to ensure the battery voltage and battery condition is within specified limits. The frequency of this testing shall not exceed three months.

The results shall be documented on the track circuit record. HR The following tasks shall be included in signalling safeworking procedures for the testing and certification of dc track circuits: T

• test track circuit relay coil voltage when unoccupied

• test battery supply voltage and current (with charger off, drain or charge as applicable) by

• inspect battery condition

25.5.4. Safety significant tasks for all track circuits

All track circuits shall be periodically tested to ensure that their shunting capabilities are within specified limits. The frequency of this testing shall not exceed two years.

The results shall be documented on the track circuit record.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following tasks shall be included in signalling safeworking procedures for the testing and certification of track circuits:

• test track circuit relay/receiver input voltage when unoccupied (except double rail 50 Hz ac and dc track circuits, as these are certified separately)

• perform fixed shunt test 04/05/2021 • perform drop shunt test

• perform polarity test as applicable

• perform zero feed test v4.0, 26. Inspection and testing of level crossing protection

ST Level crossings are interfaces where rail corridors and road/pathways intersect. This interface poses a risk which can result in a collision between users of level crossings and trains. This risk increases as rail and road vehicle speeds and volumes increase over time.

Level crossing protection takes the form of either active or passive types, as referenced in this standard. Users at level crossings are referred as road vehicles, pedestrians or cyclists, as applicable. In some cases, dedicated pathways for pedestrians or cyclists are provided at level

02000 crossings.

Active level crossing protection includes items such as type F flashing lights, bells and signage (for track and road), and can include road boom barriers, pedestrian boom barriers or swing SC gates, pedestrian lights, and pedestrian tone generators (sirens). Level crossing protection activation can be controlled locally or remotely, or enabled automatically.

Passive level crossing protection is generally provided for roads that are less utilised or for

HR private roads and usually consists of stop or give-way and warning signage only.

T Note: The requirements for passive level crossings only apply where the operator/maintainer references these as signalling assets.

At some level crossings, the activation equipment is interfaced with adjacent road traffic signals by to enable efficient management of road traffic. This aims to reduce the likelihood of road vehicle queuing across the rail corridor or the road intersection.

The requirements for road signage provided for level crossing approach warning is not covered by this standard.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

26.1. Maintenance and inspection of level crossing protection equipment

Signalling safeworking procedures shall prescribe the precautions and procedures necessary to perform inspection, maintenance and emergency response while ensuring the safety requirements of level crossing protection is afforded at all times. Additionally, signalling 04/05/2021 personnel shall be vigilant when in the vicinity of level crossings, to observe for faults, damage or vandalism that can affect its safe operation.

The moving parts of level crossing boom barriers and swing gates, including pedestrian emergency access gates where provided, shall be kept clean, lubricated and checked for

v4.0, efficient operation.

The operational time taken for booms and gates to descend/close and ascend/open shall be checked to be in accordance with the design requirements. Where these times are excessive,

ST the responsible signal engineer shall be notified and the matter investigated.

The balancing of boom barriers and swing gates shall also be checked and adjusted as necessary.

In some ac electric type gate mechanisms, particular attention shall be given to the magnetic brake and armature, to ensure that they are adjusted as necessary to compensate for brake shoe wear. The friction drive or clutch shall also be checked and adjusted as necessary. 02000

Good visibility of lights and signs at level crossings is essential. To achieve this requirement, signal lights shall be maintained in accordance with Section 22 of this standard.

SC Signalling personnel shall arrange to notify the local road authority of situations where road signs at level crossings positioned outside the railway boundary are obscured, missing, or damaged. Additionally, such advice shall be reported to the responsible signal engineer.

HR Maintenance records shall be utilised to record test values, observations and events pertaining to level crossing protection equipment. These shall be available at each level crossing site for T later reference.

26.1.1. Signal engineer's periodic inspection by

A signal engineer shall periodically inspect each active level crossing to ensure the following:

• level crossing protection equipment performs in accordance with its intended design requirement

• level crossing configuration is effective for the current circumstances (that can possibly have changed over time)

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The signal engineer's inspection is a safety significant task and shall be treated in accordance with Section 20.2 of this standard. The frequency of these inspections shall not exceed the specified period stated in Table 4.

Table 4 – Inspection frequency for level crossing protection equipment

Level crossing protection equipment Inspection frequency

04/05/2021 Lights and bells with no boom barriers/gates, not 3 months remotely monitored and tested Lights and bells with no boom barriers/gates, 6 months remotely monitored and tested Lights, bells with boom barriers/gates, not 6 months remotely monitored and tested v4.0, Lights, bells with boom barriers/gates, remotely 12 months monitored and tested

ST 26.1.2. Level crossing daily operation test

Active level crossing operation shall be tested daily, unless the level crossing is fitted with an effective remote monitor and testing device.

This daily test shall consist of a two minute load test (battery charger disconnected), checking for the correct operation of all lights, bells and boom barriers or gates, as applicable. The power supply indicator (PSI) lights where available shall be observed to be turned ON at the 02000 conclusion of the test.

This daily test shall be performed by licensed signalling personnel or qualified rail workers in accordance with network rules and network procedures. SC In addition to periodic maintenance, licensed signalling personnel shall perform a level crossing operation test whenever they investigate reports of defective level crossing protection equipment, which includes associated power supply. HR

26.1.3. Reinstatement actions following maintenance or failure T response

Fault or warning conditions, detected by a level crossing monitor, shall be cleared before by leaving the level crossing site.

Whenever level crossing lamps are replaced or re-adjusted, the level crossing shall be operated for sufficient time to confirm that the level crossing monitor’s lamp detection system (where fitted) is working correctly.

At the conclusion of maintenance, testing or investigation, it shall be ensured that the level crossing is fully operational and that nothing has been left switched off, disconnected or unlocked, including battery chargers, power supplies, test switches, emergency switches and manual operating or overriding switches.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

26.2. Treating reports of level crossing failure

All reports of level crossing protection failure shall be duly investigated by licensed signalling personnel. This includes any report of power supply defect associated with the level crossing, or any fault or warning indication provided by a level crossing monitor.

Reports of signalling irregularity pertaining to level crossing protection shall be promptly 04/05/2021 investigated by a signal engineer. The response to level crossing irregularities shall be in accordance with Section 11 of this standard.

27. Inspection and testing of signalling interlockings

v4.0, New or altered signalling interlockings are tested when commissioned to ensure that they comply with their design requirement. Subsequently, the signalling commissioner is required to provide a copy of the associated design documentation to the responsible signal engineer to

ST indicate the altered locking details as commissioned. These design documents can include locking tables, control tables, locking diagrams, circuit books, signalling plans and working sketches.

The responsible signal engineer shall be accountable for retaining the most up-to-date versions of signalling documentation relevant for the purpose of interlocking testing.

Periodic testing of mechanical and relay interlockings shall then be performed to ensure that 02000 they remain effective and in accordance with their design requirement. The responsible signal engineer shall be accountable for ensuring these interlockings are periodically tested.

Signalling interlockings shall also require testing in the following situations: SC

• when investigating a signalling irregularity or incident and there is doubt with the integrity of the interlocking

HR • whenever there is doubt with the integrity of the interlocking

• whenever mechanical locking or associated locking covers are interfered with T

The inspection and testing of signalling interlockings shall be done in accordance with SPG 0711. by

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

27.1. Authority to test signalling interlockings

Interlocking testing, including design integrity testing (also known as principles testing), shall only be performed by signalling personnel who hold the competency for such testing.

Signalling personnel holding a specific competency for interlocking testing (equivalent to an interlocking certificate) are permitted to perform the following interlocking tests: 04/05/2021

• testing of mechanical interlocking frames, including frames greater than eight levers, for any purpose

• inspection and testing of mechanical interlocking items, releasing devices and notice boards, for any purpose v4.0,

• testing of electrical and CBI interlockings, for the purpose of certifying minor new or altered work where a design integrity tester is not required

ST Note: This does not permit tester to certify complex new or altered work.

• periodical testing of electrical interlockings

Signal design engineers holding a specific competency for design integrity testing are permitted to perform the following interlocking tests:

• function testing to control tables, for the purpose of certifying minor and complex new or

02000 altered work

• design integrity testing, for the purpose of certifying minor and complex new or altered work

• periodical testing of electrical interlockings SC

Licensed signal engineers, who do not have the specific competency for interlocking testing, can perform the following interlocking tests:

HR • testing of mechanical frames of up to eight levers, for any purpose

• inspection and testing of mechanical interlocking items, releasing devices and notice T boards, for any purpose

• testing of electrical and CBI interlockings, for the purpose of certifying minor new or altered by work where a design integrity tester is not required

Note: This does not permit the tester to certify complex new or altered work.

• testing of all types of interlockings as part of an investigation when done in response to a signalling irregularity or incident, or where there is doubt with the integrity of an operating interlocking

Licensed interlocking fitters are permitted to test annett locks, duplex locks and other similar mechanical items following maintenance of these items done by them.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

27.2. Testing altered locking on interlocking frames greater than eight levers

Where a mechanical interlocking frame greater than eight levers is tested to certify an altered locking arrangement, two testers shall be required to jointly conduct the test. Both testers shall meet the same competency requirements for testing interlockings as stated in Section 27.1 of

04/05/2021 this standard.

The testing methodology shall require one tester to test the levers in accordance with the locking table as usual. The other tester shall simultaneously observe the layout plan to ensure that the relevant signalling principles are effective during the test; for example, checking that levers pulled do not clear opposing signals. v4.0, Both testers shall sign the test certificate to certify the interlocking is correct.

ST 27.3. Interlocking test certificates

Interlocking test certificates shall be provided in the following situations:

• upon certification of related new or altered works

• upon certification of periodic interlocking testing

• upon recertification of an interlocking, subsequent to a related signalling irregularity or 02000 incident

The responsible signal engineer shall retain a file of interlocking test certificates.

SC 27.4. Periodic testing of mechanical interlockings

Periodic testing of mechanical interlockings is a safety significant task and shall be treated in accordance with Section 20.2 of this standard. The frequency of this testing shall not exceed HR two years.

T Mechanical locking items and frames are subject to wear and tear. Generally, the mechanical locking does not contain any redundant locking. Therefore, the method of testing used is important to identify any fault or flaw. For example, mechanical locking that can be by inappropriately defeated, or where the inscription or indexing of items is impaired or is inappropriate.

The testing shall ensure mechanical locking items are effectively operational, safe and secure, and in accordance with specific locking tables, control tables, locking diagrams, signalling plans and working sketches as applicable.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following are examples of mechanical interlocking items that shall require testing:

• mechanical lever frames

• releasing switch locks

• annett locks

• duplex locks 04/05/2021

• half pilot staff locks

• emergency locks

• emergency switch machine locks and emergency operation locks v4.0, • token boards (or similar key release devices) and associated equipment shown on signalling plans or working sketches

• bolt locks and bracket locks ST

• loose keys

• XL locks, point-clips and point-spikes used on installed points not connected to the interlocking

• wide cut notch point lock slides

02000 Signalling notice boards shall also be checked as part of this interlocking certification to ensure that they conform to the signalling plan or working sketch.

SC 27.5. Periodic testing of relay interlockings

Relay interlockings consist of both standard relay and route control types.

Periodic interlocking testing on relay locking is a safety significant task and shall be treated in

HR accordance with Section 20.2 of this standard. The frequency of this testing shall not exceed five years. T Relay interlockings contain some safety redundancy over the interlocking and control circuitry. However, their integrity can be reduced by mechanical deterioration of electromechanical by relays, or by deterioration of wiring insulation through aging, termites, rodents, overheating, fire, lightning and so on. Additionally, electrical leakage paths can cause tracking across insulating surfaces which can impair the electrical integrity.

Some defects are identified by the system. For example, where relays are back-proved or cross-proved in the de-energised position or where the equipment fails to operate. However, other defects, such as the inadvertent bridging of an interlocking circuit may not necessarily come to attention. Therefore, the method of testing used is important to identify any fault or flaw where the relay locking has potential to be inappropriately defeated.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following elements assist to ensure the integrity of relay interlockings:

• reliable earth leakage detection equipment

• testing of busbar voltage leakage to earth

• inherent design of relay back-proving and cross-proving

Relay interlockings that fully comprise the following elements may be exempt from periodic 04/05/2021 interlocking testing:

• plug-in type vital signalling relays

• PVC insulated and sheathed wires and cables

v4.0, • double switched external interlocking circuits

• power supplies for vital interlocking circuits fitted with earth leakage detection

Note: Mechanical items that form part of the relay interlocking are tested in ST accordance with Section 27.4 of this standard.

27.6. Periodic testing of computer based interlockings

Computer based interlockings may be exempt from periodic interlocking testing. The safety integrity level required of these interlockings provides the necessary safety assurance

02000 requirements for the signalling system.

However, validation and testing of computer based interlockings is still required when affected by the commissioning of new or altered works, or otherwise when its integrity is in doubt,

SC subsequent to a signalling irregularity or incident.

Following are some computer based interlocking systems used in TfNSW heavy rail:

• Solid State Interlocking (SSI) HR • Microlok II T • Westlock

• Smartlock by • Westrace

Note: Mechanical items that form part of the computer based interlocking are tested in accordance with Section 27.4 of this standard.

28. Inspection and testing of electrical insulation

The integrity of electrical insulation used on vital signalling circuits forms an important aspect of the safety assurance requirements for the signalling system. Electrical conductors used for internal and external wiring, equipment wiring and components, and power supplies are

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

exposed to many elements and forces that subject them to deterioration and damage. This can lead to vital signalling functions being incorrectly activated by electrical leakage currents, which can result in a signalling irregularity. Therefore, the periodic testing of insulation properties of these conductors is important to ensure that they are adequately insulated from one another and from earth.

Conductors and equipment of new or altered signalling installations are initially insulation tested 04/05/2021 when commissioned in accordance with SPG 0711. Subsequently, insulation testing shall be performed periodically to identify any insulation degradation that can be caused by damage or fatigue over time. This provides a timely opportunity to action any emerging faults that are found, and avoid the impairment to signalling safety or reliability.

v4.0, Periodic insulation testing is a safety significant task and shall be treated in accordance with the requirements stated in Section 20.2 of this standard. The frequency of this inspection and testing shall not exceed the period specified in Table 5.

ST Table 5 – Maximum periodic insulation inspection and testing frequency

Testing Insulation Inspection and testing category type frequency Internal wiring PVC 4 years

Non-PVC 2 years 02000 External cables PVC 4 years and single-wires Non-PVC 2 years SC Additionally, signalling personnel shall be vigilant during other opportunities to observe the condition of wiring, cables, terminals, racking, cable routes and equipment.

The responsible signal engineer shall be accountable to ensure that all the required vital HR signalling wires and cables as shown in specific signalling documents are identified for testing. The responsible signal engineer shall also be accountable to ensure that all the electrical T conductors nominated for testing are completed in accordance with the periodic insulation testing schedule. by Insulation testing of operational signalling shall be led by a licensed signalling person. However, where the signalling is first booked out of use and disconnected from the interlocking (by a licensed signalling person), the testing may be led by an authorised signalling person holding appropriate competency.

The methodology and test equipment used for insulation testing shall be in accordance with SPG 0711.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

28.1. Detecting earth leakage

Earth leakage can be caused by two individual earth faults which are significant enough to cause an unsafe situation. Additionally, earth leakages can be made up of cumulative effects of many less-significant earth faults. The intent is to detect and rectify a single fault before another fault arises.

04/05/2021 The following are examples of the various means used to detect circuit electrical leakage paths:

• monitoring of power supply busbars using earth leakage detectors

• measuring of power supply busbars to earth using test instruments

• testing of conductor insulation using test instruments v4.0,

• function testing of signalling circuits

• examining the wiring, cables, terminals, racking, cable routes and equipment for damage ST and deterioration

28.2. Minimum acceptable values

A signal engineer shall be notified to provide instruction upon any of the following findings:

• insulation test resistance values found at or below 1 M ohm 02000 • abnormal earth leakage values

• evidence of abnormal deterioration or insulation damage

SC The requirements of Section 28.3 of this standard shall also apply where these conditions are evident.

Conductors of vital signalling circuits that are found to have an insulation test value of 200,000

HR ohms or less shall have the associated signalling apparatus booked out of use. The decision to permit signalling to remain operational in these circumstances shall be discussed between the

T responsible signal engineer and another signal engineer holding accountability before implementation, to ensure that all risks are controlled.

Note: The signal engineers involved need to have suitable experience relative to the by complexity of the subject matter.

28.3. Determination for further testing

Periodic insulation testing of external cables and single-wires is based on samples of nominated conductors. This provides an effective and efficient assessment of integrity for the conductors in use within the signalling system.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

However, comprehensive testing over and above the initial sample shall be required whenever a defect is found or is suspected. This comprehensive testing shall determine the actual condition of the cable or single-wire group.

A single-wire group is defined as the number of single conductors that are grouped together within the same routing.

04/05/2021 Where any of the sample-tested conductors are found at or below 1 M ohm, all the conductors within the cable or single-wire group shall be completely tested.

Where the conductive sheaths, screens or drain wires of external cables are tested and found at or below 1 M ohm and the associated busbar is not monitored by an earth leakage detector, the following testing requirements shall apply: v4.0, • where all working conductors of the cable are double switched, at least 20% of the cable cores shall be tested

ST • where any of the working conductors of the cable are not double switched, all the cable cores shall be tested

Working cables or single-wires that are left in these conditions shall be tested more frequently than stated in Table 5. The frequency shall be based upon the residual risk. The responsible signal engineer shall be accountable for this determination.

02000 28.4. Analysis and test records

Specific insulation test records shall be provided and kept on file along with the insulation test program for future reference. These records shall pertain to a signalling interlocking or SC block-section, as applicable. The responsible signal engineer shall be accountable for these records including the initiation of any subsequent actions that are derived from the findings.

The values recorded from insulation testing shall be duly analysed by a signal engineer to HR determine if there are any risks involved, and also to evaluate the urgency and extent of any remedial action required. T

The signal engineer shall address any degrading trend in insulation resistance values. by 28.5. Inspection and testing of power supply busbars

Voltage to earth leakage tests on power supply busbars shall be performed periodically. The frequency of this test shall not exceed three months. Each leg of the power supply shall be tested.

Under no circumstances shall an ammeter be connected between any busbar and earth.

Records shall be kept for power supply busbar voltage to earth leakage tests. These shall be retained in the relevant signalling location.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Power supply busbars that are fitted with earth leakage detectors may be exempt from periodic voltage leakage to earth testing. In these cases, the earth leakage detector shall be tested for reliable operation in conjunction with maintenance of the associated signalling location. Each occasion when an earth leakage detector has tripped, shall be duly investigated and recorded.

28.6. Inspection and testing of electrical conductor 04/05/2021 insulation

The treatment of operational signalling, when performing periodic insulation testing, shall be in accordance with the maintenance requirements stated in Section 20.1 of this standard.

Conductors shall not be removed from their terminals for the purpose of insulation testing v4.0, unless necessary. Where it is necessary, only one wire shall be removed at a time and the reconnection shall be suitably tested. The use of disconnection links or the unplugging of coded type plug couplers shall be the preferred means to perform this test. ST Electronic equipment shall be disconnected before performing insulation testing to avoid damage caused by the testing equipment.

The following are examples of such equipment that can be affected:

• power supplies

• electronic track circuit equipment 02000 • timers and timer relays

• flashing relays SC • solid state modules

• computer based interlocking equipment

• train control system equipment HR

• telemetry equipment T 28.6.1. Requirements for insulation inspection and testing of internal wiring by

Internal wiring referred in this standard is the wiring of vital signalling that is contained within signal boxes, relay rooms and trackside signalling housings. It excludes trackside cable junction boxes and the like, which only include through-connection terminals and not any internal wiring for vital signalling equipment.

The internal wiring of circuits shall be preferably tested, complete with all associated relay contacts closed. Where this is not practical, the internal circuit shall be tested thoroughly by testing all the individual parts of the circuit, arranged when the relay contacts can be closed.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The circuits shall be first disconnected from their respective power supply (at all ends) before commencing testing.

All internal wires used for vital signalling shall be tested to earth and to its associated metal frame. Where metal frames are earthed, the earth point used for insulation testing shall be the earth that is connected to the frame.

04/05/2021 The frequency of this test shall be in accordance with Table 5. However, where earth leakage detectors monitor the associated power supply busbar of internal wiring, the requirement for periodic insulation testing of internal wiring may be exempt.

28.6.2. Requirements for insulation inspection and testing of external

v4.0, main cables and single-wires

External cables and single-wires referred in this standard are the conductors that provide the external electrical connection for vital signalling that lie between signal boxes, relay rooms,

ST trackside housings and trackside equipment.

Signalling safeworking procedures shall categorise external cables and single-wires as follows:

• External main cables and single-wires – conductors that connect signalling equipment housings to one another.

• External tail cables and single-wires – conductors that connect signalling equipment

02000 housings to trackside signalling equipment. This includes track circuit cables that connect signalling equipment housings to bootleg risers, impedance bonds, tuning/matching units and the like.

SC • External power cables and single-wires – conductors that supply electrical power to vital signalling equipment

The frequency of these tests shall be in accordance with Table 5. HR Periodic testing of external cables and single-wires shall include inspection and assessment of

T wiring terminations at trackside junction boxes and equipment. The condition of conductor insulation shall be observed (where visible) for damage or degradation, such as evidence of verdigris or other corrosion. by Additionally, cable routes shall be observed for any likely damage or degradation, such as where earth works have taken place in the vicinity of buried cable routes or where trackwork has taken place near cable troughing and pits.

External cables and single-wires shall be isolated from the live (working) portion of the signalling system during testing. Lightning arrestors and surge protection apparatus associated with external cables and single-wires shall be isolated during testing. Computer based interlocking equipment and other similar electronic equipment shall be turned off before testing associated wiring.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The insulation testing requirements for external cables and single-wires shall be as follows:

• All the spare conductors of external cables and single-wires shall be tested to earth and to each other, as well as to any working conductor nominated for testing within the same cable or single-wire group. Spare conductors of tail cables and single-wires shall also be tested to the metal case of their associated trackside equipment.

04/05/2021 • A minimum amount of conductors, as specified in Table 6 shall be tested to earth and to the other conductors nominated for testing within the same cable or single-wire group. The nominated amount of conductors of tail cables and single-wires shall also be tested to the metal case of their associated trackside equipment.

• A cable that is fitted with a conductive sheath, screen or drain wire shall be tested to earth v4.0, and to each conductor nominated for testing within the same cable.

• Conductors nominated for testing including sheaths, screens or drain wires shall also be

ST tested for continuity.

• Where any working conductor of external tail cables or single-wire group is not double switched, a functional test shall be performed on the whole cable or single-wire group. This shall be done by corresponding all the input and output circuits of trackside equipment to their respective interlocking indications or controls.

• Track circuit conductors that connect signal equipment housings to bootleg risers, 02000 impedance bonds, tuning/matching units and the like shall be disconnected at both ends and each conductor tested to earth. However, where a conductive sheath, screen or drain wire is fitted to the track circuit cable, only the sheath, screen or drain wire needs to be

SC tested to earth.

An example of testing an input circuit is to open and close the contacts of a point detector while checking that it corresponds to the indications at the signaller's diagram. An example of testing

HR an output circuit is to observe all the aspects of a signal, in correspondence to its respective control, while checking for erroneous indications. T Alternatively, where the trackside equipment is provided with disconnection links, a core to core test of all the conductors may be done in lieu of performing a functional test. by Note: The functional test or the utilisation of trackside equipment disconnection links avoids the risk of disconnecting the wires.

Table 6 provides the periodic insulation testing requirements for external cables and single-wires.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Table 6 – Periodic insulation testing requirements

External cables Insulation Earth Double Minimum Additional testing and single-wires type leakage switched conductors requirements category detector circuit nominated for fitted testing External main PVC Yes Yes Nil Nil cables and 04/05/2021 single-wires No 2 Core to core test the conductors nominated for testing No Yes 2 Nil

No All Core to core test the conductors v4.0, nominated for testing Non-PVC Yes Yes 3 Nil

No 3 Core to core test the ST conductors nominated for testing

No Yes 3 Nil

No All Core to core test the conductors nominated for testing 02000 SC HR T by

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

External cables Insulation Earth Double Minimum Additional testing and single-wires type leakage switched conductors requirements category detector circuit nominated for fitted testing External tail PVC Yes Yes Nil Nil cables and single-wires No 2 Functionally test the associated trackside

04/05/2021 equipment or core to core test

No Yes 2 Nil

No All Functionally test the associated trackside v4.0, equipment or core to core test

Non-PVC Yes Yes 3 Nil ST No 3 Functionally test the associated trackside equipment or core to core test

No Yes 3 Nil

No All Functionally test the associated trackside 02000 equipment or core to core test External power PVC Yes Not Nil Nil cables and applicable SC single-wires No Not All Nil applicable

Non-PVC Yes Not Nil Nil

HR applicable No Not All Nil

T applicable

The following information provides the criteria for nominating conductors for testing:

• A spare conductor may be deemed as counting towards the minimum amount of by conductors nominated for testing.

• Where there are fewer spares than the minimum amount of conductors nominated for testing, working conductors from the outer layer of a cable shall be chosen for the testing.

• Where the outer layer is directly connected to monitored busbars the next layer shall be chosen for testing.

• External power cables and single-wires are exempt from the 'minimum amount of conductors' requirement where the associated power supply busbar is monitored by an

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

earth leakage detector. This should generally limit the scope of testing for external power cables to the cable sheaths only.

28.7. Circuits exempt from periodic insulation testing

Conductors that are used in circuits exclusively in the circumstances stated in Section 28.7.1 through to Section 28.7.3 of this standard may be exempt from periodic insulation testing. 04/05/2021

However, while conductors that are exempt from periodic insulation testing do not pose a risk to signalling safety, they can still pose a risk to reliability, personnel safety or cause a fire, in the event of insulation breakdown.

For these reasons, the requirement to periodically inspect these conductors to assess their v4.0, insulation condition shall be considered by the AEO acting on behalf of the operator/maintainer.

28.7.1. Exemptions for computer based interlocking systems ST Computer based interlocking equipment shall not be insulation tested.

The following items are examples of computer based interlocking equipment that shall not be insulation tested:

• central interlocking modules and cardfiles

•

02000 vital trackside interface modules and cardfiles

• associated vital communication equipment

• associated non-vital communication equipment SC • maintainer interface peripheral equipment

The following computer based interlocking associated conductors are exempt from periodic insulation testing: HR

• wiring directly connected to central interlocking modules, cardfiles and associated

T peripheral equipment

• input and output wiring directly connected to trackside interface modules and cardfiles by • wiring and cables used for data links

• isolated power supplies between isolation transformers and modules

• conductors on the relay-side of vital output relay circuits where fitted with an isolation module

• conductors of vital input circuits where the associated power supply busbar is monitored by an earth leakage detector

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• conductors of output circuits between the CBI equipment and steering diodes of duplicated output systems

• conductors of output circuits between steering diodes and the vital relay of duplicated output systems, and the relay return path, where the associated power supply busbar is monitored by an earth leakage detector

04/05/2021 • conductors of output circuits between the CBI equipment and controlled equipment ,where steering diodes are not fitted

• conductors of circuits from vital lamp driver cards/output modules to signal lights, where any of the following conditions are met:

v4.0, o the signal wiring is directly connected to the lamp driver card

o isolation transformers are fitted to individual lamp drives

o the signal lighting power supply busbar is monitored by an earth leakage detector ST Periodic insulation testing of wiring directly connected to computer based interlocking equipment is not normally required. However, where insulation testing is undertaken on fixed wiring associated with computer based interlockings, the interlocking equipment shall be first powered OFF and disconnected prior to the testing.

Notwithstanding the above exemptions, circuits not directly connected to interlocking modules,

02000 such as circuits emanating from relay operated circuits, are not exempt from periodic insulation testing.

SC 28.7.2. Exemptions for track circuits

Certain track circuit cables and single-wires may be exempt from periodic insulation testing. This exemption applies specifically to configurations where a breakdown of conductor insulation would not cause an unsafe failure. HR

Where the following conditions are met, the related track circuit cables and single-wires may be T exempt from periodic insulation inspection and testing:

• there is no combination of feed-end and relay-end from like track circuits that are run in the by same routing

• there is no more than one relay-end from like track circuits that are run in the same routing

Where the aforementioned conditions are not met, then each conductor of the track circuit cable or single-wire shall be tested to earth. However, if the track circuit cable has a conductive sheath, screen or drain wire, then the insulation testing requirement can be met by testing only the sheath, screen or drain wire, as applicable (individual cable core not required to be tested).

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

28.7.3. Exemptions for telephones circuits and non-vital circuits

Following are the additional specific circuits that may be exempt from periodic insulation testing:

• signalling communication (telephone) circuits

• non-vital signalling wiring and equipment where the non-vital signalling circuits are

04/05/2021 physically separated from vital signalling circuits, or otherwise where the associated power supply busbar is monitored by an earth leakage detector

29. Specific requirements for computer based interlocking systems v4.0, Computer based interlockings referred in this standard apply to the following systems:

• Solid State Interlocking (SSI) ST • Westlock

• Smartlock

• Microlok II

• Westrace

02000 • emerging computer based signalling systems

The specific requirements and precautions prescribed for computer based interlockings shall supplement the general requirements prescribed in this standard, as they pertain. They shall be

SC read and applied in conjunction with each other as necessary. For example, when securing signalling apparatus out of use that is interlocked by a Solid State Interlocking, then both the specific computer based interlocking requirements of this section and the general requirements stated in Section 13 of this standard shall apply. HR

Signalling safeworking procedures shall prescribe the specific procedures and precautions

T associated with each computer based interlocking system that is in operation within their network. by 29.1. Security of interlocking data

Computer based interlocking data, including master files, firmware and spare devices containing specific data shall be stored in accordance with type approval and manufacture's requirements. The AEO that provides accountability for the maintenance of signalling design records and interlocking data shall manage this storage.

Computer based interlocking modules shall not be unsealed or resealed by field personnel. Any module found in the field with a broken seal or no seal shall be reported to the responsible signal engineer for attention.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Only persons competent and authorised to interfere with internal components of computer based equipment shall be permitted to carry out the specific work. Generally, defective equipment is returned to the manufacturer or authorised agent for repairs. Defective equipment shall be suitably tagged with the relevant defect information such as failure date, defect details and location.

04/05/2021 29.2. Handling and storage of interlocking modules and equipment

Computer based interlocking modules contain electronic components that can be damaged by misuse or inappropriate storage. v4.0, The modules shall be handled, transported and stored with care and not subjected to damage or deterioration.

Anti-static protection handling procedures, as stated by manufacture's requirements, shall be ST applied when handling electronic boards and modules.

Interlocking modules and equipment shall be stored in accordance with type approval and manufacturer's requirements.

29.3. Interlocking system time setting

02000 Computer based interlocking system clocks shall generally be set to Australian Eastern Standard time. It is not a necessary requirement to align clock times with daylight saving time, unless preferred by the AEO acting on behalf of the operator/maintainer.

SC Where the interlocking system's architecture provides for multiple cardfiles or modules synchronised from separate maintainer interfaces, it shall be necessary to ensure that the times of all associated cardfiles and modules are set using the same time reference; for example, the

HR same laptop or smartphone clock.

T 29.4. Interlocking system site records

Each computer based interlocking shall have suitable records available on site that detail the

by versions and the type of equipment, firmware and application data in use at the specific interlocking. The following list is an example of the information required:

• interlocking hardware type and version

• application data, configuration and version

• firmware type and version

• identification information

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

These records shall be compiled by the AEO that provides the design assurance accountability and kept up to date by the AEO that provides accountability for the maintenance of signalling design records and interlocking data.

These records shall be securely retained at each central interlocking location, and accessible to maintainers and other authorised users. The responsible signal engineer shall ensure that the site records are kept in appropriate order. 04/05/2021 Any control that is enabled or disabled from a maintainer interface shall be recorded on specific maintainer control logs. These logs shall be compiled by the signalling person operating the control and kept on-site and accessible for future reference; for example, during a cold start-up of the central interlocking where previously applied maintainer controls could have been lost. v4.0, 29.5. Interfering with operational computer based interlocking equipment ST Licensed signalling personnel may interfere with operational computer based interlocking equipment to manage situations that arise on the operational system. This interference shall be done only by persons that are competent for the work and authorised to do so, and in strict accordance with signalling safeworking procedures.

Examples of interference works associated with computer based interlocking systems include the following tasks: 02000

• replace failed computer based interlocking modules and components

• rectify loss or corrupted interlocking data from memory devices or files SC • monitor communication links

• apply maintainer controls to disable or enable signalling

HR • retrieve event log information

• manage alarms T

• configure system user items such as passwords

• perform periodic or event driven maintenance, such as system time setting by

29.5.1. Maintainer interface

A maintainer interface provides access to the central interlocking. This access facilitates licensed signalling personnel to apply specific interlocking controls, review system data and event logs, manage alarms, and configure system user items, such as passwords and system time.

The distribution of passwords used to gain access to maintainer interfaces shall be restricted to appropriate signalling personnel. Passwords shall be duly controlled and registered. The

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

responsible signal engineer shall hold accountability for the management of maintainer interface passwords.

Peripheral hardware for maintainer interfaces can comprise items, such as computer terminals, support systems, display monitors, LED indicators, fault and event printers, loggers, replay facilities, control-circuit blocking-pins, remote access equipment and communications equipment. The maintainer interface can be accessed locally or remotely depending on the 04/05/2021 technology in use.

The following list provides an example of specific interlocking controls that can be enabled and disabled from a maintainer interface:

• signal aspect v4.0, • signalled route

• points operation ST • track circuit occupancy

• interlocking operation (including virtual interlockings)

Signalling safeworking procedures shall prescribe the procedures for licensed signalling personnel when applying controls to computer based interlocking systems. These procedures shall complement the general requirements of this standard (in Section 13) for securing

02000 signalling out of use.

When a computer based interlocking has been stopped, switched OFF and then restarted, any maintainer controls that were previously applied could have been lost (removed). Therefore, the

SC maintainer control log shall be checked to determine if any controls are missing as a result of the central interlocking's off-state. Any maintainer control noted missing for this reason, shall be reinstated upon restarting the interlocking.

HR Information derived from maintainer interfaces can be used as evidence when investigating serious incidents and signalling irregularities. Therefore, a failure of such equipment shall be T promptly actioned and rectified.

On some computer based interlocking systems, the diagnostic information that is displayed by by LEDs fitted on modules or cardfiles is not always fail-safe. Where this is the case, these indications shall not be used as sole information for a critical test.

On some computer based interlocking systems, an alternative means of restricting signals from clearing is available by disabling the signal's trackside module. In these cases, the signals disabled in the stop position shall have their red lights retained at all times, unless additional protection is applied in accordance with Section 13 of this standard.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

29.5.2. Removal of modules, memory devices and connections

When it is necessary to remove from operation, interlocking modules that have attached data memory devices; such as SSI memory modules, EPROMs, EEPROMs, dongles and so on; they shall be removed in conjunction with their associated memory device. A memory device is considered as an integral component of the interlocking module and thus shall remain attached.

04/05/2021 An exception to this requirement is permissible during failure situations where holdings of spare memory devices are low. In these cases, the re-use of such memory devices is permissible on the following conditions:

• the memory devices were not in-service during the original failure

v4.0, • the specific case for exception is approved by the responsible signal engineer

An exception also applies to dongles (and the like) that are specifically designed to remain correctly matched to replaced interlocking modules; for example, dongles that are secured to ST adjacent equipment racking. This exemption is granted on condition that the dongles retained for use are free from defects, malicious code or viruses, are not corrupt, and contain only the correct data for the specific application.

In all cases (whether retained or removed), modules and their memory devices shall be suitably labelled indicating their identity and version.

02000 When placing modules into service, they shall be pre-fitted with their correct memory device. The module's total compatibility and correct configuration shall be assured before making the module operational for service.

SC Modules shall not be disconnected unless first powered down or otherwise as prescribed by manufacture's requirements. Signalling safeworking procedures shall prescribe the disconnection process for each interlocking type in use.

HR Note: In some computer based interlockings, when point-modules are replaced or powered OFF and powered ON, the points will not always show a detection status.

T Subsequently, upon restoring power to a points module, the signaller is required to key the associated points to the last known position so that detection can be restored.

by The removal of interlocking modules and circuit boards shall be in accordance with type approval or manufacture's requirements. An example of this requirement is for the earthed-metalwork frame to be touched with both hands unless an earth strap is utilised.

The responsible signal engineer shall be notified of all computer based interlocking module replacements. The timing of this notification shall be commensurate with the level of authority bestowed to the signalling personnel tasked with the work.

Module and cardfile retaining screws and plug couplers shall be fully secured before restoring power.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Care shall be taken not to swap external connections to modules, circuit boards or cardfiles, otherwise damage can occur. In some cases where external connections are swapped, the equipment can display different indications to the intended design.

Restrictive coded fixtures, fittings and wiring of modules, cardfiles, dongles, plug couplers and the like shall be periodically checked to ensure that their security is effective. These checks shall ensure that the effectiveness of the mechanism used for inserting only the correct item and 04/05/2021 the electrical connections are in proper working order. Any associated labelling shall be checked to be in proper condition. The frequency of these checks shall be done in accordance with technical maintenance plans.

When lamp driver modules are replaced, the lamp voltages for the associated signals shall be v4.0, checked and adjusted as necessary.

Where Microlok II diagnostic workstations utilise the communications network for safety critical communications, the diagnostic workstation connection shall be disconnected from the safety ST critical communications network while not in use. This requirement may be exempt where fully duplicated Microlok II systems are used. In such cases, one diagnostic workstation may be left connected.

29.6. Authority to upload or program interlocking data

The configuration of interlocking data for computer based interlocking systems, including 02000 associated items such as memory modules, EPROMs, EEPROMs, executive files, application files, network configuration files, compiled processor units and so on shall be done only by personnel competent for the work (for example, a Signal Design Engineer), and engaged by the SC AEO that provides the design assurance accountability.

Limited delegation of authority in this regard may be transferred to licensed signalling personnel holding relevant competency and engaged by the AEO acting on behalf of the HR operator/maintainer.

T This delegation of authority shall be limited to the following tasks:

• uploading of data files, in accordance with specific installed data forms

by • programming of EEPROMs and other similar devices, where these items have failed in service, in accordance with specific installed data forms

• adjustments to adjustable computer based interlocking items (including dip switches), where these adjustments are made in accordance with specific installed data forms, or to specified limits, where relevant

Procedures for these delegated tasks shall be explicitly prescribed in signalling safeworking procedures.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The delegation of authority shall not for any reason permit changes or reconfiguration of interlocking data. The delegation of authority shall be granted to rectify failure situations only and not to initiate new or altered works.

Where devices have been altered, reprogrammed or have data reloaded, verification shall be obtained, as necessitated by type approval requirements to attest the interlocking data and settings are correct. This shall be done prior to bringing such items into operational use. These 04/05/2021 requirements shall be explicitly prescribed in signalling safeworking procedures. The responsible signal engineer shall be notified of such work.

Where it is necessary to replace an EEPROM dongle in conjunction with a Microlok II object controller, it shall be necessary to obtain independent verification of the Microlok II object v4.0, controller's configuration files. The responsible signal engineer shall be notified of EEPROM dongle replacement.

ST 29.7. Tools and test equipment used on computer based interlocking systems

Tools and test equipment used on computer based interlocking systems shall meet the ASA specifications or as deemed acceptable by the relevant manufacturers. The use of such equipment shall be done in conjunction with instructions relative to the specific type of interlocking in use. For example, only the correct tool shall be used to remove and insert 02000 EPROMs and EEPROMs from circuit boards, or only specified devices shall be used for monitoring or interrogating interlocking data.

Conventional test equipment such as multimeters, data loggers, chart recorders and SC oscilloscopes shall be used only where they do not pose a risk to the functional safety of the system.

Inappropriate use of test equipment and test leads can effectively bridge-out or bypass safety HR functions, resulting in a less restrictive input and consequently, an unsafe output. Test equipment can also potentially force an output to produce a less restrictive situation. T

The following restrictions apply for the use of conventional test equipment on computer based interlocking systems: by • test equipment shall have an input impedance of 1 M ohm or greater for the voltage measurement

Note 1: Multimeters which have a low ac impedance mode for voltage measurements (for example, Fluke 289) cannot be used for fault finding when in this mode.

Note 2: External shunts should not be fitted to test equipment when fault finding.

• multimeter current mode shall not be used when testing; current measurements shall be performed using a tong meter or current clamp

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• multimeter ohms and diode-test modes produce a test voltage; use of these modes shall consider the risk of the test voltage turning ON an input or output

• test equipment inputs shall be floating; not referenced to a common potential

• multi-channel test equipment shall have all channels isolated from each other

• test equipment lead probes shall be chosen and applied so as to minimise the likelihood of 04/05/2021 probes causing a short-circuit across an input

Test equipment that enables writing of data, generation of telegrams or messages, or issues simulated controls or indications pose a risk to operational signalling. These are typically used for the purpose of testing during commissioning or specific failure rectification. If used

v4.0, inappropriately, false information can be transmitted to the operational signalling system.

The use of these devices on operational signalling is strictly prohibited. Before connecting such devices, the affected and protecting signalling shall be first booked out of use. ST These devices shall only be used by persons authorised by the responsible signal engineer or signalling commissioner. They shall not be kept on-site. They shall be stored in a similar manner to storing critical computer based interlocking design records and data. These devices shall be managed by the AEO that provides accountability for the maintenance of signalling design records and interlocking data.

Go/no-go testers shall be used to functionally test relevant computer based interlocking 02000 modules, as applicable. These tests shall be executed and the equipment cycled in accordance with manufacturer's instructions before the modules are installed into the working system. Modules retained as site-spares shall be tested using a go/no-go tester before placing into SC service. This also ensures that any module used from another interlocking is cleared of its previous data identity and history.

Modules associated with a signalling irregularity or significant incident shall not be placed in a HR go/no-go tester or other testing device that erases data or configuration memory, until the investigation matters are resolved; otherwise the contents of the module's memory can be T erased.

Third party applications, such as MS Excel and MS Word shall not be used on maintainer by interface systems or operational signalling systems unless otherwise permitted in accordance with type approval and manufacture's requirements.

Third party devices such as USB sticks shall be free of viruses or malicious software before inserting into computer based interlocking systems.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

30. Surveillance inspections

Surveillance inspections shall be performed to meet the primary and secondary objectives as prescribed in this standard. The primary objectives are directed towards signalling safety, reliability, and technical capability. The secondary objectives are directed towards signalling operational efficiency, sustainability and its environmental impact. Additionally, surveillance 04/05/2021 inspections provide an opportunity to effect stakeholder relations along with prompting consideration for initiatives of continual improvement.

The following is a list of primary objectives:

• monitor the standard of signalling maintenance v4.0, • monitor the condition of signalling assets

• monitor the level of compliance to relevant signalling standards, technical maintenance

ST plans, engineering instructions and other such documents

The following is a list of secondary objectives:

• monitor the efficiency and effectiveness of maintenance

• monitor the efficiency and effectiveness of the signalling system

• monitor any adverse environmental impact caused by signalling infrastructure 02000 • communicate directly with signalling personnel in the course of their work, giving them the opportunity to directly raise issues and receive feedback on signalling matters

SC • communicate directly with network operators and other signalling stakeholders

Surveillance inspections shall be conducted by experienced signal engineers. Other signalling personnel may be engaged as enablers for meeting the inspection requirements. However, this

HR shall not negate the requirement for a signal engineer to personally conduct periodic inspections. T The responsible signal engineer shall be accountable to ensure surveillance inspections are conducted accordingly.

by The surveillance inspections shall form part of the AEO's assurance regime for the provision of safety and reliability of the signalling system.

30.1. Scope of surveillance inspections

Surveillance inspections shall include in-depth examination and tests of judiciously selected items and activities from selected areas of aging or brand new installations. The inspections shall include checks of point locks and detector adjustments, track circuit history records and level crossing records as applicable.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following is an example of specific signalling that can be targeted for inspection:

• assets that are difficult to access

• assets that are awkward to maintain

• assets that are maintained by inexperienced persons

• assets that have a poor performance history 04/05/2021

Surveillance inspections shall include observation of signalling safety critical and safety significant tasks. This shall be done to determine elements of compliance to procedures and standards and to ascertain technical capability.

Surveillance inspections shall also include visits to signal boxes and control centres to liaise v4.0, with network operators on the effectiveness of the signalling system from their perspective.

Note: Liaison with train crew is achieved during front of train signal sighting inspection,

ST done in accordance with Section 22.1 of this standard.

30.2. Scheduling of periodic inspections

Periodic surveillance inspections shall be performed on an annual basis, as a minimum.

The scheduling shall be such that an adequate inspection sample is conducted of no less than 20% of the area of accountability, eventually covering the whole area over a five year period. 02000 While it is not practical for surveillance inspections to cover every single asset over the five year period, the scope of inspections and observations shall adequately achieve the objectives listed.

SC Apart from scheduled inspections, other opportunities can exist for signal engineers to capitalise on fulfilling the scope of surveillance inspections.

An example of these opportunities includes the following tasks:

HR • mechanical interlocking testing

T • signal sighting inspections

• level crossing inspections

by • project site integrity meetings and practical completion inspections

• signalling irregularity and failure follow-up investigations

30.3. Surveillance inspection reports and action requirements

The results of surveillance inspections shall be recorded in a specific report. The report outcomes shall contain an itemised asset list of the inspection area, details of inspectors and the details of any personnel observed or stakeholders engaged. The report shall also include

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

action requirements for the rectification of defects. These actions shall be priority based and time scaled. A defect management system shall be used to manage this requirement.

The report shall also contain recommendations, as applicable to the inspection. The recommendations can include increased supervision or local instructions to correct deficiencies, asset renewal programs, training plan requirements and improvements to procedures, standards and so on. 04/05/2021 Signal engineers shall also record occasions where they have directly observed personnel performing signalling related tasks, particularly safety critical and safety significant tasks.

The responsible signal engineer shall be accountable to ensure that surveillance inspection reports are duly produced and actioned accordingly. v4.0, 31. Housekeeping and protection of signalling assets

ST Signalling trackside apparatus and equipment housings shall be kept clean and tidy, and left in a secured state when not being worked-on.

Equipment housings shall include relay rooms, walk-in enclosures, location cupboards, and lower floors of signal boxes. These shall be kept locked whenever possible to prevent unauthorised access and vandalism. Spares and materials shall not be stored in these places, unless they are appropriately placed on racks or cupboards provided specially for the purpose.

02000 Highly inflammable material shall not be stored in these places. Locking arrangements shall be maintained in good condition.

Before securing signalling apparatus or housings, licensed signalling personnel shall check that

SC everything is in order and properly connected and that nothing has been left loose, foul of standard clearances, or in a potentially unsafe condition.

Access pathways, ladders and other such items shall be maintained in good order, so as to

HR provide adequate access to signalling apparatus and housings. Excess vegetation, rubbish or surplus materials shall be removed during maintenance visits. T Lighting of relay rooms and cupboards shall be maintained in good order to ensure adequate visibility is available. by The responsible signal engineer shall be advised of any security breach, water ingress or fire, or any other significant matter that requires escalation and their attention.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

31.1. Prevention of water ingress to signalling equipment

Maintenance of signalling equipment shall be performed to keep insulating surfaces between electrical terminals clean and free from water to prevent leakage currents.

Trackside signalling apparatus, housings, conduits and the like shall be properly sealed to prevent the ingress of rainwater. The drainage around electrical signalling apparatus shall be 04/05/2021 examined to ensure that water does not build up and enter the equipment.

Signalling personnel when performing maintenance shall look for signs of water leakage and take corrective action.

Maintenance during wet weather, which would allow water to enter the equipment, should be v4.0, avoided.

Signalling housings and vulnerable equipment shall be checked for water leaks following heavy rain. Equipment shall be cleaned, dried and lubricated as necessary, and where evidence of ST water ingress is evident, the equipment shall be checked for correct operation.

31.2. Prevention of fire around signalling equipment

Maintenance of signalling equipment shall be performed to prevent fires occurring in and around signalling equipment and signal boxes. 02000 Combustible materials shall be cleared from trackside signalling equipment such as signal boxes, relay rooms, trackside equipment housings, trackside equipment, cables, air lines, air reticulation equipment, pits and ducts. SC The underside portion of elevated relay huts and equipment cupboards shall be enclosed to prevent the accumulation of rubbish.

HR 32. Control of signalling documentation

T Signalling safeworking procedures shall set out the responsibilities and requirements for the control of signalling documentation. These documents pertain to maintenance documentation issued to the field which include as-built copies, interim maintenance copies, commissioned by stage-work copies, modification sheets, and marked-up copies of any temporary repairs, paralleled contacts, and like for like renewals that are pending update.

The following are examples of typical signalling documents, as referenced in this standard:

• circuit books

• signalling plans, track plans and working sketches

• track insulation plans

• locking tables, locking diagrams, lever nameplates diagrams

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

• control and indication panel layouts

• control tables

• interlocking data

• modification sheets

•

04/05/2021 air system diagrams and air reticulation plans

• detailed site survey diagrams

• equipment layout diagrams

v4.0, 32.1. Requirements for signalling documentation control

All personnel involved with the production, installation, maintenance, and use of signalling documentation shall have a responsibility for ensuring that the documents accurately depict and

ST correspond to the as-built status, as applicable. They shall promptly advise of any discrepancies and arrange to have them corrected without delay.

All copy holders shall ensure that they utilise the latest version of controlled documents.

The despatch and receipt of all field-issued signalling documentation shall be supplemented by a transmittal notice.

02000 The responsible signal engineer shall be accountable for maintaining a document control system for all field-issued signalling documentation.

The following are examples of the responsible signal engineer's accountabilities for signalling

SC documentation control:

• identifying appropriate location and quantity requirements, such as signalling housings, signal depots, office copies and so on HR • managing the distribution of new and updated documents, destroying of superseded copies and the management of transmittals for issued copies T

• auditing the versions of all field issued copies every 12 months

•

by certifying corrections and updates as necessary, including corrections emanating from like for like renewals, field paralleling of contacts, temporary repairs that become permanent changes, known discrepancies and so on

• arranging updates for as-built signalling documents

Field issued signalling documentation shall be treated as an asset, and duly maintained in good condition.

Signalling documentation accountabilities for licensed signalling personnel shall be stated in signalling safeworking procedures.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

The following are examples of licensed signalling personnel's accountabilities for signalling documentation control:

• maintaining signalling documents in a satisfactory condition, keeping them bound and secure, ready for use, and updated with the latest amendments

• retaining signalling documents (when not in use) at their nominated location and available

04/05/2021 for failures and other referencing needs

• advising the responsible signal engineer to arrange replacement copies as required

• marking-up and signing (in red pen), signalling documentation following any like for like renewals, paralleling of contacts, temporary repairs, or known and obvious corrections to

v4.0, remedy a discrepancy with the as-built installation, pending the issue of updated copies

• advising a signal engineer of any discrepancies between the signalling documents and the as-built installation, or red mark-ups as a result of work ST • booking out of use vital signalling equipment, where a discrepancy poses an imminent risk to the safety of the signalling system, until instructions are received from a signal engineer

• destroying superseded copies as directed

• ensuring the availability and temporary retention of issued maintenance copies along with interim maintenance copies and commissioned stage-work copies while project works are

02000 in progress

33. Control of signalling security locks and keys SC Signalling housings and equipment, including trackside apparatus and cable pits shall be secured and locked when not being worked-on to prevent unauthorised access and vandalism. Some cable pits and older type trackside apparatus that cannot be locked due to their design,

HR such as signal branch EP plunger lock boxes or indication boxes/escapement slides, may be exempt from this requirement. T The Falcon series locking system is generally used to secure signalling infrastructure, including the provision of dual access locks for entering common signalling and communication housings, by and common signalling and electrical housings. At some locations, older style locks may still be in use on trackside equipment.

Railway specific locks such as SL and XL are used to prevent unauthorised operation of signalling apparatus. The design requirement of these locks and keys is not covered by this standard.

Signalling housings shall be locked using Falcon 4 locks. Signalling equipment shall be locked using Falcon 8 locks. Access doors to interlocking machines where electric locks are in use, shall be locked using Falcon 8 locks.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

Signalling security locks shall be maintained such that they remain effective and in proper condition. Damaged or defective locks shall be immediately replaced.

Note: Falcon series and older style locks used within the heavy rail network, as governed by TfNSW may be in use across other operated railway networks in NSW.

33.1. Lock types in use 04/05/2021

The following system of locking is used for securing signalling equipment housings and apparatus:

• Falcon 4 (signalling housings)

v4.0, • Falcon 8 (signalling apparatus)

• Falcon 17 (dual access lock for common signalling and communication housings)

• Falcon 22 (dual access lock for common signalling and electrical housings) ST

• Older style locks that can still be in use in some areas include the following key types:

o Best series 7 and 8

o Yale series 6, 9 and R

o SWI (safeworking instrument) – old and new 02000 o ESML (emergency switch machine lock)

o STEL Corbin – old and new SC o

33.1.1. Falcon series

The Falcon locking series is a hierarchical arrangement utilising a plurality of locks and keys, HR wherein each key series can engage the lock tumbler for a defined set of locks. The lock

T tumbler uses an interchangeable core with a restricted key broaching.

The Falcon series has a capability of being extended by adding further locks and keys. However, only the nominated keys for Falcon series locks, as listed in Section 33.1, shall be by used within the heavy rail network, as governed by TfNSW. Any requirement to extend the series of locks and keys within the hierarchy shall require approval from the ASA.

33.1.2. Locktech series

An approved alternative supplier of lock cylinder cores and keys exists with Locktech Industries. The profiles of Locktech and Falcon keys are slightly different. The Locktech cores can be pinned similar to Falcon locks and can be opened by either a Locktech key or Falcon key; however, Falcon locks cannot be opened by Locktech keys.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

33.1.3. Older style locks

Older style locks, as listed in Section 33.1, should be phased out in favour of the Falcon series as appropriate.

33.1.4. SL and XL locks

04/05/2021 SL locks are used to control operational access to signalling apparatus; for example, when the apparatus is booked out of use. SL keys are issued to network operators for the purpose of operation and to licensed signalling personnel for the purpose of engineering.

XL locks provide a higher level of security by restricting the issue of XL keys. For signal engineering, only responsible signal engineers and signalling commissioners shall be issued v4.0, with XL keys.

XL locks are used to control operational access to signalling apparatus in the following

ST situations:

• when the apparatus is seldom used (for example, emergency crossovers)

• when the apparatus is booked out of use for extended periods

• where installed points, pending removal or commissioning, are not connected to the interlocking 02000 • where a higher level of security is required

Responsible signal engineers and signalling commissioners may temporarily transfer their issued XL key to specific licensed signalling personnel. The method of transfer shall be SC prescribed in signalling safeworking procedures, and granted in accordance with a valid signalling permit to work. A transmittal stating the reason for the transfer and period of issue shall be provided on each occasion. The transmittal shall be kept by the relevant party.

HR The XL key holder shall be accountable for its safe custody. T 33.2. Major signal boxes and control centres

Major signal boxes and control centres are fitted with proprietary card type security access by systems. The management of these systems is not covered by this standard; however, only persons authorised for access shall be issued with access cards to signalling rooms within these buildings.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

33.3. Configuration and key cutting

The AEO acting on behalf of the operator/maintainer shall be responsible for the configuration control of all signalling security locks and keys.

The AEO shall use a system to control and record the configuration of locks and the cutting of signalling security keys. 04/05/2021

The configuration and cutting of Falcon locks and keys, and the other signalling security locks and keys (excluding SL and XL) shall be performed by a qualified locksmith who is a member of the Master Locksmiths Association, the Locksmiths Guild of Australia or other such recognised locksmiths’ organisation. Appropriate supervision by a licensed signal engineer shall be v4.0, afforded to the work to ensure that the security of the pinning charts is retained.

The AEO acting on behalf of the operator/maintainer shall hold all Falcon and other signalling security key and lock blanks (excluding SL and XL) and arrange for the cutting and numbering ST of keys, ensuring that the allocation of numbers are unique and in accordance with the AEO's key control system.

Each new key issued shall be stamped with the key series number, a unique allocation number and with the words, ‘TfNSW DO NOT COPY’.

33.3.1. Control and distribution 02000

The AEO acting on behalf of the operator/maintainer shall be responsible for controlling the distribution of keys.

SC The AEO shall utilise a system to control and record the distribution of signalling security keys. Signalling security keys shall only be issued to signalling personnel, and only in conjunction with a valid signalling permit to work.

HR The AEO may permit an allocation of signalling security keys to another contracted AEO for signalling works, as permitted by the operator/maintainer in accordance with signalling

T safeworking procedures, and network rules and network procedures. This arrangement shall be agreed by all parties and shall be duly documented by the AEO allocating the keys.

by Lost, stolen or improper use of signalling security keys shall be considered as a breach of signalling safeworking and shall be dealt with accordingly by the relevant AEO.

Dual access keys for common signalling, communication and electrical housings may be provided to signalling personnel in accordance with a valid signalling permit to work. Dual access is provided by a Falcon 17 lock and key for common signalling and communication housings and a Falcon 22 for common signalling and electrical installations. The AEO responsible for the respective discipline shall issue these keys.

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

34. Storage and dispatch of operational safeworking keys

Operational safeworking keys and tokens are used by network operators to operate specific signalling apparatus for the purpose of train running.

The following are examples of keys types as referenced in this standard: 04/05/2021

• half pilot staffs

• bank engine keys

• shunting keys v4.0, • annett keys

• guards keys

ST • closing keys

• token board keys

• ESML or EOL keys

• XYZ keys

• fortress keys used on signalling apparatus 02000 • level crossing emergency operation keys

Licensed signalling personnel may use these keys for the purpose of maintenance, but not for

SC train operations.

34.1. Temporary storage of operational safeworking keys

HR The storage requirements for operational safeworking keys when taken temporarily out of use by licensed signalling personnel shall be prescribed in signalling safeworking procedures. T The following are examples of storage requirements:

• keys stored in a suitable locked safe, or appropriate lock-up area under the control of the by responsible signal engineer

• keys clearly labelled, giving full particulars

• detailed records of keys in storage or transit, kept up to date in regards to movements, controlled by the responsible signal engineer

Superseded T HR SC 02000 ST Mandatory Requirements for Signalling Safeworking Procedures Version 3.0 Issued date: 30 September 2016

34.2. Dispatching operational safeworking keys for repair, replacement or cancellation

A specific record shall be used when despatching operational safeworking keys for repair, replacement or cancellation, for the purpose of transmittal and tracking. The following details shall be included on the record: 04/05/2021 • reason for the dispatch

• key details

• name of all dispatchers

• name of all recipients v4.0,

• date of transactions

The record shall be progressively compiled by the relevant stakeholders throughout the various ST stages of dispatching and receiving. Abbreviations shall not be used to describe station names or other details. The record shall be controlled by the responsible signal engineer.

Operational safeworking keys shall be dispatched in a suitable box locked with an SWI padlock (or similar) accompanied by the record.

The responsible signal engineer shall account for the content of keys when dispatched and

02000 received. When operational safeworking keys are returned, the responsible signal engineer shall inspect the key inscription and number, and if correct, permit the distribution of the keys for operational use.

SC The end receiver shall forward the completed record back to the responsible signal engineer for retaining the file. HR T by

Superseded