1. Line Blockage Guidance for Planners & GZAC
Operational Close Call Line Blockage Group 1
24-Mar-14

2. Rule Book and Standards Guidance
Guidance to Signallers Rule Book TS (V01)
Guidance to IWA/COSS/PC Handbook (V02)
Guidance to Planners NR/L2/OHS/ (V03)

3. Background
Following a number of issues of interpretation that of have resulted in confusion between Signallers, Track workers and Planners regarding the “correct” signals to be agreed during the process of taking a line blockage . This subject has been discussed at the National Operational Close Call Line Blockage group.
The intention is to produce further guidance for all groups that is acceptable across the three disciplines.
Attached are three briefings, one for each group giving guidance on what is expected when planning a line blockage, requesting a line blockage and granting a line blockage
Above all, the underlying principle is making sure that the correct protection is given to the track workers and that signallers and planners are supported in the decisions they are making. 3
24-Mar-14

4. Principle of a Line Blockage
What does the Planner, Signaller, IWA, COSS or PC need to understand when planning, requesting or granting a line blockage?
Where is the work activity taking place?
This should include the access to the site of work and any protection requirements.
Which lines will be affected during the work activity?
How will the activity be protected?
What signals will be used to protect the activity? (a protecting signal must be identified for each line that will be affected by the work) e.g. Diagram 1 – Up Main L6 Diagram 2 AB4-AB19
What other signals will be kept at danger to protect any route that leads towards the line blockage? e.g. Diagram 1 – Up Branch L8 Diagram 2 AB6-AB8-AB21
What points need to be set so that trains can be signalled normally on unaffected routes? (away from the line blockage) e.g. Diagram 2 – Up Main AB15
Will the safety of the line be affected and what additional protection would be required?
Agreement by all parties what additional protection is going to be used. 4
24-Mar-14

5. Guidance – the Rule Book states:
If a request for a line blockage is received by the signaller you must agree with the IWA, COSS or PC:
the line to be blocked
the nature of the work
the locations between which the work will take place
the amount of time needed to do the work
the time after which permission can be given for the line blockage to start
which signals will be kept at danger to protect the activity
any additional protection needed if the work will affect the safety of the line
the arrangements if single line working is taking place
the arrangements at any level crossings affected by the line blockage
What does this mean to a planner when they receive a request for a line blockage? 5
24-Mar-14

6. Planner Guidance
The Planner must prepare a plan that clearly identifies;
which running lines are affected by the work
the precise location of the work to be undertaken
The protecting signals for the work
The Planner must make sure that the submitted plan is approved through publication in the WON, Signal Box Instructions or Signallers GZAC Daily List (Status of Accepted or With Changes in SSOWPS2)
The Planner must issue the safe system documentation pack to the IWA/COSS/PC at least a shift in advance
The Planner must make appropriate amendments to plans in response to valid feedback being received
The Planner should refer to other submitted plans for Line Blockages so they avoid independently applying for blockages where others have already applied (consider PC option if appropriate). 6
20-Mar-14

7. GZAC Guidance
The GZAC (current title Possession Support Assistant) shall receive and process all line blockage applications received into Green Zone Planner (via SSOWPS2 or Directly input) to check that they;
Clearly identify the location of work
Clearly identify a valid protecting signal for each line affected by the work
Do not clash with WON published items, agreed Signal Box Instructions or other applications in the system
Do not cause Signaller work load limits to be exceeded
The GZAC should try to facilitate different work groups sharing line blockages under a PC by directing different Planners towards each other 7
20-Mar-14

8. Diagram 1 Simple Line Blockage8
20-Mar-14

9. IWA/COSS/PC Guidance
The IWA/COSS/PC shall receive a safe system of work pack including an RT9909 and RT3181 that;
Clearly identifies the location of work
Clearly identifies a protecting signal(s) for each line affected by the work
The IWA/COSS/PC should receive the pack for Verification at least a shift in advance
The IWA/COSS/PC must check that the protecting signals stated on the pack actually provide protection for the work to be undertaken on the running line (s) affected
During the safety conversation with the Signaller record on the RT3181 & repeat back the details of all/any other signals maintained at danger by the Signaller. 9
20-Mar-14

10. Diagram 2: Bi-directional lines & working clear of points
Signaller will expect the IWA/COSS/PC to identify where they are working and what signals on that line are required as protection. (Signals highlighted in Red)
The Signaller and IWA/COSS/PC will have a safety conversation that will agree which signals will be kept at danger to protect the activity (Signals highlighted in Blue)
Also what Signals can be used as normal, this may include maintaining a set of points in a specific position, for routes that do not affect the site of work. (Signals highlighted in Green) 10
20-Mar-14

11. Guidance - IWA/COSS/PC RT3181 contents
The IWA/COSS/PC, have an RT3181 form where the columns in Section 2 – Blocking the Line are currently headed as shown below…
It is completed to the convention illustrated
Provided that the actual work mileage area is totally within the limits shown on the RT3181 – the arrangements can be implemented during the safety conversation.
The Signaller will determine any other signals to be maintained at danger or routes to be set with appropriate reminder devices fitted during the safety conversation.
From Controlled Signal
From C/O Points
To defined Exit location
Running Line A
Running Line B
(Uni directional line)
From Controlled Signal
From C/O Points
From Controlled+BiDi Sig
To defined Exit location
Running Line C
Running Line D
(BI directional line) 11
20-Mar-14

12. Closing Slide 12
20-Mar-14