Page:UK Traffic Signs Manual - Chapter 8 - Part 2- Traffic Safety Measures and Signs for Road Works and Temporary Situations) - Operations 2009.pdf/157

 The advance warning vehicles and monitor vehicle should then proceed to the pre-agreed marker post locations. The monitor vehicle should be located within sight of a matrix or VMS signal so that their operation can be confirmed, and the advance warning vehicles should be positioned 500 m and 1000 m upstream of where it is planned to establish the closure.

The supervisor should instruct the personnel in the monitor vehicle to conduct a flow count; the operation should not take place if the flow traffic exceeds 1200 vehicles per hour per lane left open (60 vehicles in 3 minutes per lane left open) at the work site, the limit for using the technique referred to in Section O11.4.

At this time, the supervisor should advise the control office in order that the VMS signs/signals show the appropriate symbols for the operation and should check that there are no incidents on the highway that will conflict with the planned operation.

Before the run commences, the personnel in the monitor vehicle should confirm that the matrix signals have been activated.

When the supervisor is satisfied that the operation can proceed, he/she should radio to the closure vehicles to this effect. The LMCC on the closure vehicles should now be lowered if this has not already been done. The closure vehicles and the hard shoulder vehicle should then join the traffic stream in the near side lane behind one another (Plan MCC6, Phase 1).

When the vehicles pass the advance warning vehicles on the hard shoulder, the flashing amber lanterns on the signs on the warning vehicles should be switched on. When the closure vehicles are ready to establish the closure (Plan MCC6, Phase 2), the supervisor should direct that the blind on each closure vehicle should be raised to uncover the "CONVOY VEHICLE NO OVERTAKING" sign, and the red cross and flashing red warning lights should be switched on.

When directed by the supervisor, the closure vehicles should move into the appropriate lane to become line abreast, and the hard shoulder vehicle should move to the hard shoulder. The sequence is shownin Plan MCC6, Phases 3 to 6.

The closure control vehicle should then signal for the closure vehicles to slow down progressively to the agreed closure speed of either 20 or 30 mph.

The monitor vehicle should be positioned in front of the closure vehicles and should keep station with the rear of the traffic moving away in front of the closure.

The advance warning vehicle T1 (see Plan MCC5) should keep station 500 m to the rear of the queue that forms, and vehicle T2 should maintain a position 500 m behind vehicle T1. 155