Road surfaceWallonia

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Traffic signs

Traffic rules

Wallonia

57. Road surface

A road surface warning indicates that the road ahead may be uneven, damaged or in poor condition and could affect the stability, steering or braking of a vehicle. The hazard may include bumps, depressions, potholes, broken pavement or other irregularities in the road surface.

Drivers should reduce speed where necessary, maintain a safe distance and avoid sudden steering or braking when passing over an irregular surface. The exact meaning and appearance of the warning sign vary between countries, so drivers must follow the local traffic signs and regulations.

Cobblestone road with an asphalt strip on Vladslostraat. (Bovekerke, Belgium)
Wikimedia.org • LimoWreck • CC BY-SA

Which Belgian sign warns about an uneven road surface?

The Belgian A13 warning sign currently warns of a transverse depression or hump in the carriageway that may require drivers to reduce speed significantly.

Warning for a bad road surface.

Signal routier A13 • Cassis ou dos d'âne.

Verkeersbord A13 • Uitholling overdwars of ezelsrug.

What should you do when you see an A13 sign in Belgium?

Observe the road ahead carefully and adapt your speed to the condition of the road. You should approach at a speed that allows you to pass the irregularity safely without losing control or causing danger.

Does the Belgian A13 sign impose a specific speed limit?

No. A13 is a warning sign and does not itself establish a numerical speed limit. Drivers must nevertheless adapt their speed to the road condition, and a separate speed-limit sign may impose a lower maximum speed.

Does A13 currently mean any damaged road surface in Belgium?

Not yet. Under the Road Code currently in force, A13 specifically refers to a transverse depression or hump. Its meaning will become broader when the new Code of the Public Road enters into force.

When will the meaning of the Belgian A13 sign change?

From 1 June 2027, A13 will warn of an uneven road surface or a road surface in poor condition. This broader meaning will replace the current definition referring specifically to a transverse depression or hump.

Is A13 the same as the Belgian raised-road warning sign?

No. A14 warns of an officially constructed raised traffic-calming feature on the public road. A13 currently warns of a transverse depression or hump that represents a road-surface hazard.

Is A13 the same as the slippery-road sign?

No. The Belgian A15 sign warns of a slippery carriageway. A13 concerns an irregularity in the shape or condition of the road surface rather than reduced grip.

Is there a special speed rule for an A13 road-surface warning?

There is no special fixed speed attached to A13. Belgian drivers must always adapt their speed to the condition of the road, visibility, traffic and other circumstances and must be able to stop for a foreseeable obstacle.

Can a supplementary sign indicate how long the hazard continues?

Yes. A supplementary sign may indicate the length of the dangerous section. Warning signs can also be accompanied by information indicating the distance to the hazard where appropriate.

Where are Belgian warning signs normally placed?

In Brussels and Flanders, warning signs are generally placed approximately 150 metres before the danger. If special circumstances require a different distance, a supplementary sign indicates the approximate distance to the hazard.

Should motorcyclists and cyclists take extra care at an A13 warning?

Yes. Depressions, humps and other surface irregularities can disturb the balance and direction of two-wheeled vehicles. Riders should approach at an appropriate speed and avoid abrupt steering or braking where possible.

Uncontrolled crossroad

Ring road

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