Matrix signs, a red cross and a queue in the rain
You are driving a three-lane Dutch motorway at 19:15 in steady rain. Permanent signs on this stretch show 120 km/h. Ahead, an overhead gantry carries a red circle containing '70' above lanes 1 and 2, and a red cross above lane 3. Two hundred metres beyond, a second gantry shows '90' with no red circle above lanes 1 and 2, and a green arrow above lane 3. You are in lane 2 at 100 km/h with a lorry 12 m behind you. Five hundred metres ahead, brake lights are coming on in lane 1 and the queue there is already down to walking pace. There is standing water in the wheel tracks. Your exit is 900 m ahead, on the right, and you have not yet moved over.
1. What is the legal status of each signal at the first gantry, and how long does each one apply?
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Each signal has to be read separately:
- Red circle around '70'. The circle is what makes the number binding. From the gantry onwards the maximum speed over lanes 1 and 2 is 70 km/h, and the 120 on the permanent signs is suspended. It stays in force until it is cancelled, normally by an end-of-measures sign or by a later display, not because you have driven past the gantry.
- Red cross above lane 3. The lane is closed. You may not use it, from this gantry until the closure is lifted.
- '90' without a red circle at the second gantry. That is an advisory speed, a warning that something ahead justifies driving more slowly. Exceeding an advisory is not in itself an offence, but it does not raise the binding 70 either; only a new speed shown with a red circle replaces it.
- Green arrow above lane 3 at the second gantry. That reopens lane 3 from that point.
Because it is raining hard and there is standing water, the binding 70 is also the sensible speed: aquaplaning risk climbs steeply above roughly 80 km/h with this much water in the wheel tracks.
2. You still have to reach your exit. How do you plan the next 900 m with the lorry 12 m behind and the queue forming in lane 1?
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The constraint is that everything you do must be predictable for a lorry that cannot stop as quickly as you and is sitting inside the gap you would normally use for braking.
- Lose speed early and gradually. Off the accelerator first, then progressive brake pressure. A late, hard application in standing water gives the lorry no time and risks a loss of grip at your own wheels.
- Warn if the queue appears suddenly. A brief touch of the hazard lights is the accepted way to flag a queue to traffic behind, then cancel them. It is far more effective than a brake light that the lorry driver may only register late.
- Plan the lane change to the exit as a merge, not a dive. Lane 1 is already at walking pace; you cannot join it at 100 km/h. Match the speed of the queue end and slot in behind it, then leave at the exit.
- If you miss the exit, take the next one. Crossing the solid line before an exit, cutting across the chevrons or using the hard shoulder to make the exit are all offences and, in a queue, dangerous ones.
If the lorry keeps closing up, increase your own gap ahead so that you never have to brake hard for the queue.