Manual of Air Traffic Services Part 1:
At aerodromes where taxiway stop-bars are used to protect taxiway routes and
runways from inadvertent incursions controllers are not to clear aircraft to cross an
illuminated stop-bar. The inoperable taxiway stop-bar and its associated taxiway
should be withdrawn from service and an alternative routing used. On the occasions
when this is not possible an aircraft may be cleared to cross such an illuminated
taxiway stop-bar subject to the following conditions:
a) The stop-bar cannot be suppressed.
b) The stop-bar and aircraft affected are visible to the aerodrome controller.
c) The phraseology used is to leave the pilot in no doubt that the clearance applies
only to the faulty stop-bar.
d) In the case of illuminated stop-bars protecting the runway aircraft may not be
cleared to cross without the assistance of an aerodrome operations vehicle.
NOTE: The requirement at b) above may be satisfied by the use of an SMR which
has been approved by the CAA for this purpose.
