Road surfaceWorldwide

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99. 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.

Warning for uneven surface. Warning for a bad road surface. Warning for a bad road surface. (Berlin-Blankenfelde, Germany)
Wikimedia.org • Lukas Beck • CC BY
What does a road surface warning mean?

A road surface warning indicates that the surface ahead may be uneven, damaged or otherwise capable of affecting the safe movement of vehicles.

What kinds of road defects can the warning indicate?

Depending on the country, it may warn of bumps, depressions, potholes, broken pavement, uneven repairs or other surface irregularities.

What should you do when you see a road surface warning?

Reduce speed where necessary, increase your awareness of the road ahead and be prepared for changes in the vehicle's stability or direction.

Does a road surface warning impose a specific speed limit?

Not normally. A warning sign alerts drivers to a hazard rather than establishing a numerical speed limit. A separate speed-limit sign may be used where a particular maximum speed is required.

Should you brake before reaching an uneven road surface?

Where slowing is necessary, it is generally safer to reduce speed before reaching the irregular surface rather than braking sharply while travelling over it.

Why can an uneven road surface be dangerous?

A severe surface irregularity can affect tyre contact, steering, braking and vehicle stability. It can also damage tyres, wheels or suspension components.

Are motorcycles and bicycles particularly affected by uneven surfaces?

Yes. Two-wheeled vehicles can be particularly sensitive to potholes, ridges and other irregularities because these hazards may disturb their balance or alter their direction suddenly.

Is an uneven-road warning the same as a slippery-road warning?

No. An uneven-road warning concerns the physical condition or shape of the road surface. A slippery-road warning concerns reduced tyre grip caused by the surface or conditions such as water, ice, mud or other substances.

Can the warning apply over a longer section of road?

Yes. A supplementary sign may indicate the distance to the hazard or the length of the affected section, depending on the country's traffic-sign system.

Should you increase your following distance on a poor road surface?

Yes, when conditions require it. Additional distance provides more time to react if the vehicle ahead slows suddenly to avoid a pothole or other surface defect.

1 Worldwide 2 Motorway 3 Expressway 4 Residential area 5 Built-up area 6 Zone 7 Speed limit 8 Minimum speed 9 Advisory speed 10 Footpath 11 Bike path 12 Shared-use path 13 Separated path 14 Pedestrian warning 15 Tunnel 16 Bridge 17 Cycling street 18 Pedestrian zone 19 Speed bump 20 Toll road 21 Customs 22 One-way traffic 23 Quay 24 Slope 25 Bus lane 26 Bus stop 27 Dead end 28 Stop sign 29 Give way 30 Roundabout 31 Priority road 32 Road narrowing 33 Priority over oncoming traffic 34 Give way to oncoming traffic 35 Pedestrian crossing 36 Railway crossing 37 Mandatory direction 38 Turn prohibition 39 School area 40 Overtaking 41 Crossing animals 42 Slippery road 43 Rockfall 44 Aircraft 45 Curve 46 Chevron 47 Wrong-way driving 48 Roadworks 49 Crosswind 50 Height limit 51 Width limit 52 Length limit 53 Weight limit 54 Radar speed sign 55 Selective barriers 56 Low-emission zone 57 Intersection direction sign 58 Priority at the next junction 59 Traffic lights 60 Traffic lights warning 61 Pedestrian lights 62 Road markings 63 All-way stop 64 Junction layout 65 Climbing lane 66 Bike box 67 Left-hand traffic 68 Speed feedback 69 Driving licence 70 Location marker 71 Road number 72 Countdown markers 73 Public toilet 74 Rest area 75 Traffic mirror 76 Emergency telephone 77 International border 78 Pedestrian underpass 79 Cycling route 80 End of restriction 81 Parking 82 No parking 83 No stopping 84 Parallel parking 85 Park and ride 86 Kiss and ride 87 Alternate-side parking 88 Parking meter 89 Parking disc 90 Disabled parking 91 Traffic management 92 Merging 93 Reversing 94 U-turn 95 Carpool 96 Traffic jam 97 Detour 98 Uncontrolled crossroad 99 Road surface 100 Advisory cycle lane ...