Lane control signal indicating that vehicles may not proceed along the lane directly beneath the signal
Lane control signal indicating that vehicles may not proceed along the lane directly beneath the signal

Tidal flow lane control

Lane control signal indicating that vehicles may not proceed along the lane directly beneath the signal

Lane control signal showing the lane below is closed. This sign is common on smart motorways and tidal-flow systems. In the theory test it tests your understanding of lane control signals and the need to obey the red 'X'. Always move out of the closed lane immediately.

Diagram reference
5003.1, 5003.0

Where you'll see this sign

Smart motorways and tidal-flow systems.

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