Lesson 11 of 18 · Hazards

Road surface, works and wind

Identify the cause of the warning and choose speed, distance and position before the hazard.

Learn the signs

A31 Glat vej

Unusually slippery road

What it means: Read the plate explaining the cause. Adjust speed and following distance and avoid abrupt braking or steering.
Your action: Read the plate explaining the cause. Adjust speed and following distance and avoid abrupt braking or steering.
Common mistake: Do not assume the warning applies only to ice: the plate may describe wet-road slipperiness.

Full card and sources ↗

UA31 Isglat

Slippery because of ice

What it means: With A31, this plate identifies ice as the cause of the slippery-road warning. Reduce speed and allow a larger stopping margin.
Your action: With A31, this plate identifies ice as the cause of the slippery-road warning. Reduce speed and allow a larger stopping margin.
Common mistake: It specifies the hazard; it does not give a numerical speed or guarantee that all ice is visible.

Full card and sources ↗

A33 Løse sten

Loose stones and chippings

What it means: Reduce speed on the loose material and leave space from other vehicles to reduce the risk of stone impact.
Your action: Reduce speed on the loose material and leave space from other vehicles to reduce the risk of stone impact.
Common mistake: The risk is stones thrown by tyres, not rockfall from a hillside as on A34.

Full card and sources ↗

A34 Stenskred

Rockfall and fallen rocks

What it means: Watch both the slope and the road for fallen rocks. Adapt speed so you can stop before an obstruction.
Your action: Watch both the slope and the road for fallen rocks. Adapt speed so you can stop before an obstruction.
Common mistake: The warning includes rocks already on the road, not only rocks visibly falling now.

Full card and sources ↗

A35 Farlig rabat

Dangerous verge or road edge

What it means: Read any cause plate and keep a safe position away from an unsafe verge or high edge.
Your action: Read any cause plate and keep a safe position away from an unsafe verge or high edge.
Common mistake: The problem is not always soft ground: a height difference at the edge is another possibility.

Full card and sources ↗

A36 Bump

Speed bump

Your action: Reduce to a suitable speed before reaching the hump. Read any accompanying speed information.
Common mistake: The picture does not give one universal safe speed for every hump and vehicle.

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A36.1 Bump

Active traffic-calming dip

What it means: The shown plate says the device is active at high speed. Reduce speed in good time and follow the applicable limit.
Your action: The shown plate says the device is active at high speed. Reduce speed in good time and follow the applicable limit.
Common mistake: Do not mistake this active dip for an ordinary fixed bump, or treat its activation point as a new speed limit.

Full card and sources ↗

Example road scene with A36.1 (illustration) — **Example on the road** Illustration: the street is AI-made, the sign is the official drawing.

A37 Ujævn vej

Dangerously uneven road

What it means: Reduce speed before the uneven section and leave enough space to control the vehicle over the surface.
Your action: Reduce speed before the uneven section and leave enough space to control the vehicle over the surface.
Common mistake: This warns of unevenness; it does not necessarily mean a deliberately installed speed bump.

Full card and sources ↗

A38 Lunke

Depression: water may collect

What it means: Reduce speed before the depression; heavy rain can leave water across the carriageway.
Your action: Reduce speed before the depression; heavy rain can leave water across the carriageway.
Common mistake: The specific warning is water collecting in a low point, not simply a hidden view beyond a dip.

Full card and sources ↗

A39 Vejarbejde

Roadworks

What it means: Expect workers, changed road layout or obstructions. Slow down, read temporary signs and follow the marked route.
Your action: Expect workers, changed road layout or obstructions. Slow down, read temporary signs and follow the marked route.
Common mistake: The warning itself does not specify a numerical speed limit or guarantee that your usual lane stays open.

Full card and sources ↗

A95 Sidevind

Side winds

What it means: Expect crosswinds and changes in wind force when leaving shelter. Adjust speed and allow room for affected vehicles.
Your action: Expect crosswinds and changes in wind force when leaving shelter. Adjust speed and allow room for affected vehicles.
Common mistake: The windsock symbol is a hazard warning, not a mandatory travel direction.

Full card and sources ↗

Recall: name each sign

Similar signs, different decisions

Look at the exact symbol first, then read the difference.

A33Loose stones and chippings

A34Rockfall and fallen rocks

A33 concerns stones thrown from loose material. A34 concerns rockfall and rocks that have fallen onto the road.

A36Speed bump

A36.1Active traffic-calming dip

A36 warns of a traffic-calming bump. The shown A36.1 installation has an active-at-high-speed plate; read it together with the applicable speed limit.

What would you do?

Answer without looking back. Your first check is kept as your result. This is practice, not an official exam.

Lesson result

Sources and review date

Reviewed: 2026-10-17. Study explanations are our wording; use official rules and your instructor’s guidance.

Road markings order 425, 13 April 2023

Færdselsstyrelsen — category B, May 2026

Danish Road Traffic Act 118, 12 January 2026

Vejdirektoratet — A36.1 and its active-at-high-speed plate