82
LEVEL CROSSINGS
20.4 Countdown markers
20.4.1. Countdown markers to diagrams 789, 789.1 and 789.2 (S2‑6‑6, see
Figure 20-23
) may
be used to emphasise the approach to a level crossing. They are intended
to divide into equal
lengths the distance between the first marker, with three bars, and the crossing. The
first marker
should be co‑located with the warning sign to diagram 770, 771 or 772 (see
20.1
). Unlike
the countdown markers
on the approach to a junction, the bars do not represent intervals of
100 yards, as the warning sign will usually be less than 300 yards from the crossing.
If the signs
are duplicated on the off side of the road, for greater emphasis
or to improve visibility, the slope
of the bars is reversed.
20.4.2. Where queues sometimes extend upstream
of the crossing warning signs, especially if
the end of the queue
might be hidden by a bend, queue warning signs might be necessary.
The signs are reversed when mounted on the off side
789
789.1
789.2
Figure 20-23 Countdown markers to railway or tramway level crossing (S2‑6‑6)
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