Description
This document describes the requirements for authorising, issuing and using a Track Work Authority (TWA).
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Purpose
To prescribe the rules for authorising, issuing, and using a Track Work Authority (TWA).
Principle
A TWA:
- authorises occupancy of a defined portion of track between rail traffic movements
- does not give exclusive occupancy of the defined portion of track
- is requested by and issued to the Protection Officer
- may include multiple worksites
- allows work that breaks or obstructs the track or alters track geometry or structure.
Drivers and Track Vehicle Operators must follow instructions given by Handsignallers and the Protection Officer.
Issue of a TWA
The Signaller must get the Network Controller’s authority to issue the TWA.
A TWA is a spoken authority, a form is not required.
Rail traffic
Protection Officers must manage rail traffic approach to, and passage through, the TWA.
Before allowing workers to re-enter the Danger Zone, Protection Officers must make sure that:
- the protection has been replaced, and
- rail traffic has passed beyond the limits of the worksite.
Handsignallers must replace railway track signals on the line immediately after each rail traffic has completely passed their location.
Protection Officer
At all times there must be a nominated Protection Officer for a TWA.
The Protection Officer must:
- get the TWA, and
- be the only person to speak to the Signaller about protection arrangements, and
- protect workers from rail traffic, and
- make sure that worksites are protected against the unauthorised entry of rail traffic, and
- be the only person to tell workers about:
- the locations of safe places, and
- the safety measures in place, and
- the extent of the area protected, and
- changes to protection arrangements.
- make sure that the protection is in place before work starts.
When requesting a TWA, the Protection Officer must identify the worksite limits in kilometres, the line names and nominate the worksite kilometres as being between:
- two signals, or
- a signal and the end of a terminal line.
Signals must be identified by their numbers.
Nominating the worksite kilometres as being between signals or between a signal and the end of a terminal line, provides only a guide to the Signaller to locate the worksite limits on the track indicator diagram.
Protecting worksites
The Danger Zone must not be occupied before the TWA has been issued and protection is in place.
Where possible, Protection Officers must protect worksites by placing railway track signals and Handsignallers at signals protecting the worksite.
Where there are no protecting signals, Protection Officers must place Handsignallers and railway track signals at the TWA limits.
Effective communication must be maintained between the Protection Officer and:
- the Signaller, and
- Handsignallers.
Protection Officers must make sure that all points of entry into worksites are protected against unauthorised rail traffic.
The Protection Officer, in agreement with the Signaller, may reduce the number of points of entry to a worksite by making sure points are clipped and locked to exclude rail traffic.
The Protection Officer must make sure that worksites are protected against unauthorised rail traffic entry before restoring the points for use.
Points may be unclipped to allow rail traffic movements into and within the TWA limits, only if, the Protection Officer has made arrangements to advise the Driver or Track Vehicle Operator to proceed:
- at normal speed, or
- at caution, or
- under special conditions.
Where the protection arrangements of adjoining TWA worksites would overlap, the worksites must be managed as multiple worksites under a single TWA.
Protecting worksites by setting signals at STOP
A worksite may be protected by setting signals at STOP on the approach side of the worksite.
At locations where controlled absolute signals are available, these signals must be used to protect the worksite.
Controlled absolute signals must be:
- set and kept at STOP with blocking facilities applied, and
- cleared only if it is safe to allow rail traffic to pass through the worksite.
Automatic signals may be used to protect the worksite if:
- the signals are booked out of use for the duration of the TWA by a Maintenance Representative, or
- the signals are fitted with a signal key switch and can be operated to protect the TWA.
In remotely controlled locations where signals or routes cannot be remotely blocked, a Qualified Worker must cut in the local control panel to set and keep signals at STOP for the duration of the work.
To use signals to protect worksites, Protection Officers must use one of the following methods:
1. If there are two controlled absolute signals within 500m before the worksite, an inner Handsignaller must be placed at the first signal reached by approaching rail traffic. An outer Handsignaller is not necessary.
2. If a signal between 500m and 1000m before the worksite can be set at STOP, an inner Handsignaller must be placed at that signal. An outer Handsignaller is not necessary.
3. If there are no signals within 1000m before a worksite:
- an inner Handsignaller must be placed between 500m and 1000m before the worksite, and
- an outer Handsignaller must be placed at a signal that can be set at STOP, within a further 2500m from the inner Handsignaller.
The distance between the outer and inner Handsignallers must not be greater than 2500m.
If the distance between the outer and inner Handsignallers is less than 2500m, the outer Handsignaller must warn Drivers and Track Vehicle Operators about the reduced distance to the inner Handsignaller.
Protecting with Handsignallers only
An inner Handsignaller must be placed at least 500m, and not more than 1000m, from the worksite in the direction of approaching rail traffic.
An outer Handsignaller must be placed 2500m from the inner Handsignaller in the direction of approaching rail traffic.
Worksite Warning
If a platform is located between the inner and outer Handsignallers, a WORKSITE warning sign must be placed beyond the departure end of the last platform before the inner Handsignaller.
Affected signals
If signals will display STOP because they are affected by work on track, the Protection Officer must:
- tell Signallers about the affected signals before starting work, and
- place Handsignallers at the affected signals.
Once rail traffic has stopped at an affected automatic signal, Handsignallers must follow the Protection Officer’s instructions about allowing rail traffic to proceed, and at what speed.
The Protection Officer must direct Handsignallers at affected controlled absolute signals to get the Signaller’s authority to allow rail traffic to pass the signal at STOP.
Protecting signals that cannot be cleared
A clearance Handsignaller must be placed beyond the worksite at the first running signal that can display STOP if:
- a protecting signal cannot be cleared, and
- the Protection Officer cannot be sure that the line is clear between the worksite and the first running signal beyond the worksite that can display STOP.
The clearance Handsignaller must report to the Protection Officer when rail traffic has passed complete beyond the clearance location.
The clearance Handsignaller must not do other work.
Approaching worksites
Before authorising inner Handsignallers to allow rail traffic to approach worksites, Protection Officers must make sure that:
- workers are in safe places, and
- the track is unobstructed and safe for the passage of rail traffic.
Only Protection Officers may tell Handsignallers whether to allow rail traffic to proceed, and at what speed.
The Protection Officer must direct Handsignallers at controlled absolute signals to:
- ask the Signaller to clear the signal, or
- get the Signaller’s authority to allow rail traffic to pass the signal at STOP.
Handsignallers at automatic signals must allow rail traffic to proceed only if the Protection Officer directs them to do so.
Multiple worksites
Worksites more than 3500m apart must be managed under separate TWAs.
Worksites less than 1000m apart must be treated as one worksite.
If the protection arrangements of adjoining worksites would overlap, the worksites must be managed as multiple worksites under a single TWA.
A designated Protection Officer must coordinate rail traffic passage through the worksites.
The inner Handsignaller located at the first worksite must issue Drivers and Track Vehicle Operators a NRF 011 Worksite Warning form.
Handsignallers and three railway track signals must be placed at least 500m, and not more than 1000m, from each worksite in the direction of approaching rail traffic.
A CLEARANCE sign or Handsignaller must be placed at least 50m beyond the last worksite.
Drivers and Track Vehicle Operators may resume normal speed after the rear of the last vehicle has passed the CLEARANCE sign or the Handsignaller.
Adjacent lines
If the safety assessment indicates that workers need to be protected from rail traffic on adjacent lines, the Protection Officer must arrange for safety measures to be implemented in accordance with NPR 712 Protecting work from rail traffic on adjacent lines.
The Protection Officer may arrange for the speed of rail traffic on adjacent lines to be restricted.
Slip sites
If a signal at STOP protects a slip site, Drivers and Track Vehicle Operators must follow the directions on the instruction sign on the signal.
X, Y and Z keys
If bidirectional running has been prevented by withdrawing an X, Y or Z key, protection is needed only in the normal running-direction.
Converging lines
If adjacent signals on converging lines are used to protect a worksite a single Handsignaller must be placed in a safe place, where approaching rail traffic on either line can be seen, and:
- railway track signals placed at each signal, or
- railway track signals placed beyond the crossovers, and
- if necessary, place an additional Handsignaller responsible for placing and removing railway track signals.
Platforms
Where a platform prevents railway track signals from being placed within 20m beyond the fixed signal:
- a Handsignaller must be placed at the protecting signal, and
- railway track signals must be placed beyond the end of the platform, and
- if necessary, place an additional Handsignaller responsible for placing and removing railway track signals.
Where an additional Handsignaller is used, the Handsignallers must maintain effective communication.
When railway track signals are placed beyond crossovers or platforms, worksites must not be established within 500m of the railway track signals.
Terminal lines
If the Signaller tells the Protection Officer that there is no rail traffic between the worksite and the end of a terminal line or balloon loop, protection from that direction is not necessary.
Tonnage signals
A tonnage signal affected by work on track or being used to control rail traffic approaching the worksite, must be set, and kept at STOP and a Handsignaller must be placed at the signal.
Before authorising the Driver of a prescribed train to pass a tonnage signal, the Protection Officer must make sure that the train can pass through the worksite to the last signal controlling the tonnage signal. This signal might be as many as three signals beyond the tonnage signal.
A clearance Handsignaller must:
- be placed at the signal controlling the tonnage signal, and
- tell the Protection Officer when the line is clear for rail traffic as far as that signal.
Liaison
The points of contact between Signallers and work groups for matters of worksite protection must be the:
- Protection Officer, and
- Handsignallers placed at controlled absolute signals.
The Protection Officer must:
- tell the Signaller about protection applied to lines adjacent to the TWA, and
- tell the Signaller about work progress, and
- if necessary, seek an extension of time.
Change of Protection Officer
An outgoing Protection Officer must tell the incoming Protection Officer about the worksite protection arrangements.
The incoming Protection Officer must:
- tell Signallers about the changed contact details, and
- record, in permanent form, the handover details.
Fulfilling the TWA
The TWA may be fulfilled only when the Protection Officer:
- arranges for work to continue under another work on track authority, or
- tells the Signaller that:
- the worksites have been cleared, and
- protection has been removed, and
- the portion of track included in the TWA is certified as available for use.
The Protection Officer must tell the Signaller about operating restrictions that have been placed or removed.
Work to continue under another work on track authority
If arrangements have been made to continue work under another work on track authority, the Protection Officer must make sure that the protection for the TWA is not removed until the new work on track authority is issued and the required protection is in place.
The Signaller must make sure that the track within the limits of the work on track authority:
- is clear of rail traffic, or
- is occupied only by associated rail traffic permitted under that Authority.
Keeping records
Network Controllers and Signallers must record, in permanent form, the TWA details.
The Protection Officer must record, in permanent form:
- the TWA details, and
- the protection arrangements for worksites, and
- details of communications about:
- Train Running Information, and
- changes to the worksite protection arrangements.