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Signals and Signs

NSG 614 Blocking facilities

This document describes the requirements for using blocking facilities.

Version 3.3, 4 December 2022


This document describes the requirements for using blocking facilities.

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To prescribe the rules for using blocking facilities in the Network.


Blocking facilities are facilities or devices used by Qualified Workers to prevent:

  • unintended issue of Proceed Authorities, or
  • operation of signalling or point equipment.

Unless allowed in these Rules, equipment with blocking facilities applied must not be operated.


Unless you are assured by the Signaller, do not assume that:

  • signals have been set at stop, or
  • points have been correctly set, or
  • blocking facilities have been applied.

Management of blocking facilities

Before applying blocking facilities to signals or points, Signallers must make sure that affected points are in the correct positions.

Temporary removal

Blocking facilities may be temporarily removed from controls:

  • to set a different route using the same controls, or
  • after safe arrangements have been made, to clear a signal to permit a movement over the blocked route, or
  • for inspection, maintenance and testing of the signalling equipment, or
  • with the agreement of the Possession Protection Officer or Protection Officer to allow a work train or track vehicle to enter or exit the limits of a Local Possession Authority (LPA) or a Track Occupancy Authority (TOA).

Blocking facilities must be restored to controls as soon as the activity that required their temporary removal has been completed.

Permanent removal

Blocking facilities must be removed from controls when the conditions that required their application no longer exist.


Signallers must record, in permanent form, the removal and application of blocking facilities:

  • for inspection, maintenance and testing of signalling equipment, or
  • to allow entry to the limits of an LPA or a TOA.