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18
- Signs for road works and temporary situations
Signs may provide information about the location of current or future
road works where delays or road closures are expected. This gives
drivers the opportunity to allow more time for future journeys,
use alternative routes, or make other arrangements for the duration
of the works
On the approach to major road works, especially on motorways and
dual carriageway roads, signs may indicate the nature and duration
of the worksThe
Signs for lane closures and contra-flowsystems on motorways and
dual carriageway roads
These signs show the distance over which the reduced number of lanes
continue through the road works. The signs are repeated at regular
intervals, usually every ½ mile. In these examples, there are no
lane restrictions such as a width limit. The vertical black line
indicates that the left-hand lane is the hard shoulder. The white
downward-pointing arrow indicates a contra-flow traffic lane separated
by traffic cylinders . Where the contra-flow lane is separated by
a physical barrier or a buffer lane (a lane closed to traffic),
the white arrow is not shown
Temporary signs indicating lane priority at junctions
Where slip roads leave and join at junctions within a road workssite,
the permanent arrangement for lane drop, lane gain andtraffic merge
may be temporarily changed. Signs may beprovided to show the temporary
arrangements.
Signs for works traffic
Where it is necessary for works vehicles to gain entry to or exitfrom
the works site itself, access may be directly from or to theopen
traffic lanes, such as a break in the line of cones. Theseentry
and exit points are marked by red and white signs. Driversshould
take care not to follow works vehicles into the site and tokeep
a lookout for vehicles leaving the site. These vehicles arelikely
to be moving more slowly than other traffic. Red and whitesigns
may also be used to direct works traffic at road junctions.
Convoy working
At some road works, other than on motorways, it may benecessary
to slow traffic to a speed of 10 mph. To ensure thesafety of both
road users and the workforce, traffic is takenthrough the works
in convoy. At the start of the convoy section,traffic is controlled
by either traffic signals or "STOP/GO" boards(see page 136). You
must wait, where indicated, for the convoyvehicle that will escort
you though the works. On singlecarriageway roads you must not overtake
the convoy vehicle. Ondual carriageway roads you may overtake the
convoy vehicle, if itis safe to do so, after you have passed through
the works areaand signs have indicated that the speed limit has
changed to ahigher limit. Where traffic signals are used at the
start of theconvoy section, the red signal may show for a period
longer thanyou would normally expect: do not proceed until the green
lightshows. Convoy working may take place at any time during theday
or night.
Mobile road works and lane closures
Some road works can be carried out without the need for roadclosures
or major traffic management schemes. The area of workis protected
by a large stationary or slow-moving vehicle with asign mounted
on the back.
On single carriageway urban roads with a speedlimit of 30 mph or
less, the works will always beon the near side in the direction
of travel. A "keepright" sign will be mounted on the back of theworks
vehicle or the vehicle protecting the works.There may also be a
"keep left" sign on the front of the vehicle tobe viewed by traffic
travelling in the opposite direction. Additionalstatic "road works
ahead" signs may be placed at the side of theroad and may include
a distance plate such as "For 1 mile" or"Grass cutting for 1 mile".
There may also be "road narrows onthe left" signs. The vehicle will
usually have flashinglamps on its roof. The type of work likely
to be carried outincludes grass cutting, weed spraying and gully
emptying. Onsome busy roads, traffic may also be controlled by "STOP/GO"boards
On single carriageway roads with a speedlimit of 40 mph or more,
the "keep right"sign on the back of the works vehicle orthe vehicle
protecting the works includesflashing amber lamps. These lamps flash
inpairs from top to bottom.
On motorways and dual carriageway roads,mobile lane closures may
be introduced oneither the left-hand or right-hand side of thecarriageway.
More than one vehicle will beused to protect the lane closure. All
signswill have flashing amber lamps. A lightarrow may supplement
the white-on-blue"keep right" or "keep left" arrow, and flashalternately
with the amber lamps at the top.
On the approach to mobile works on amotorway or dual carriageway
road,vehicles with signs indicating the lanes thatare closed will
be on the hard shoulder orat the side of the carriageway. The type
ofwork undertaken includes line painting,minor repairs and setting
out static roadworks signs.
Mobile carriageway closures may be used to convoy traffic whenit
is necessary to hold traffic back while cones and signs aremoved
to change a temporary contra-flow system, or perhaps toremove an
overhead cable. All lanes on thecarriageway will be closed, but
traffic willmove slowly forward, over a distance ofseveral miles,
on the approach to the areawhere the work is being undertaken. By
thetime the convoy reaches this area, theworks should have been
completed, trafficwill be allowed to increase its speed andtraffic
lanes will be opened. The convoyvehicles will have a large red cross
and redlamps flashing in vertical pairs.
Temporary traffic control
At some road works sites on singlecarriageway roads where two-way
trafficflow is not possible, it is necessary toalternate the direction
of flow by trafficcontrol. This is known as shuttle working.For
short lengths, this may be achieved bymanually-operated "STOP/GO"
boards ateach end. At other sites, portable trafficsignals will
be used. They operate in thesame way as permanent traffic signals.
Normally, a stop line is notmarked on the road. A sign is used insteadto
indicate where you must stop when thered signal shows.
Temporary signals may be used to control a road junction. In thiscase,
the red signal is likely to stay on longer than for normalshuttle
working, as traffic on each leg of the junction will passthrough
the road works separately. There may be a junction withina length
of road subject to shuttle working that is not controlledby signals.
Signs will warn drivers of this.
Miscellaneous temporary signs
Where a mandatory speed limit is imposed at a road works site, advance
warning may be given, especiallyon motorways and high-speed dual
carriageway roads. However, this sign is less likely to be used
in the future: the first speed limit sign will be located at the
pointwhere the speed limit commences
The end of a temporary mandatory speed limit is indicated by the
"end of road works" sign. However, the message may be reinforced
by a sign indicating the permanent speed limit beyond the road works.
This may be combined with the "end of road works" sign. Where the
permanent limit after the works is different from that in advance
of the works, a speed limit sign is always used. The national speed
limit sign shown in the example is varied to the appropriate limit
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