This guide explains the most important Dutch theory points about speed and distances: safe speed choice, stopping distance, following distance, fog, and aquaplaning. These are common Category B exam topics because they test whether you can adapt your speed to the road, weather, and visibility.
Why this topic matters
Speed questions are not only about remembering a number on a sign. In Dutch theory, the real test is whether you understand that the posted speed is only the maximum allowed in normal conditions. In poor visibility, rain, or slippery conditions, the safe answer is often a lower speed and a larger following distance.
Key rules in 60 seconds
Aquaplaning risk
- Higher speed increases the risk of aquaplaning.
- Poor tyre condition and incorrect tyre pressure increase the risk.
- Water-filled ruts and standing water make the situation more dangerous.
If aquaplaning happens
- Stay calm and keep the steering as steady as possible.
- Ease off the accelerator gently.
- Do not brake hard or steer sharply.
- When grip returns, adjust speed smoothly.
Fog lights
- Front fog lights: only when visibility is seriously reduced by fog, snow, or rain.
- Rear fog light: only in fog or snowfall when visibility is less than 50 metres.
- Rear fog light is not for normal rain.
Safe speed
- Always choose a speed that lets you stop within the distance you can see is clear.
- In fog, heavy rain, or darkness, this often means driving below the posted maximum.
What the exam asks most often
- What is stopping distance?
- Why does higher speed increase aquaplaning risk?
- When may you use the rear fog light?
- How much distance should you keep from the vehicle in front?
- What is the difference between the posted maximum and a safe speed?
Detailed guide
Safe speed comes first
In Dutch theory, one of the most important rules is that you must be able to stop within the distance you can see is clear. This means that even if the speed limit is legally higher, you must slow down when visibility, grip, or traffic conditions are worse.
Stopping distance
Stopping distance is the total distance from the moment you notice danger until the vehicle stands still. It consists of:
- Reaction distance — the distance travelled while you react.
- Braking distance — the distance travelled while the car slows down to a stop.
A common theory simplification is to use about one second of reaction time, but in real life reaction time can be longer because of fatigue, distraction, or stress.
Following distance
A safe following distance gives you time to react and brake smoothly. In normal conditions, many learners use the two-second rule as a practical guide. In rain, fog, snow, or darkness, the gap should be larger.
Aquaplaning
Aquaplaning happens when the tyres can no longer clear enough water, so the contact with the road is partly lost. The car may feel as if it is floating, and steering or braking will work much worse.
What increases the risk?
- Higher speed
- Standing water and road ruts
- Worn tyres or poor tread
- Incorrect tyre pressure
What should you do?
- Stay calm.
- Ease off the accelerator gently.
- Keep the steering movements small and smooth.
- Avoid sudden braking or sharp steering until grip returns.
Fog and visibility
Fog questions are very common in the theory exam because they combine speed choice, following distance, and lighting rules. The safe answer is usually to reduce speed early, increase distance, and use the correct lights only when the legal condition is met.
- Rear fog light: only in fog or snowfall with visibility under 50 metres.
- Front fog lights: allowed when visibility is seriously reduced by fog, snow, or rain.
- Drive slowly enough to stop within the visible clear distance.
Maximum speeds: general exam overview
- Built-up area: usually 50 km/h unless signs show otherwise.
- Outside built-up area: usually 80 km/h unless signs show otherwise.
- Autoweg: usually 100 km/h unless signs show otherwise.
- Motorway: often 100 km/h between 06:00 and 19:00; outside those hours the applicable speed depends on the road and signs.
Common mistakes to avoid
- Driving at the posted maximum even when visibility is poor.
- Using the rear fog light in rain.
- Braking sharply during aquaplaning.
- Ignoring tyre condition and tyre pressure in wet weather.
- Following too closely in fog or heavy rain.
Quick FAQ
The total distance from noticing danger until the car stands still: reaction distance plus braking distance.
Because the tyres have less time to clear water and can lose contact with the road.
Only in fog or snowfall when visibility is less than 50 metres.
You must be able to stop within the distance you can see is clear.
Relevant Dutch law and exam context
- RVV 1990, Art. 19: you must be able to stop within the distance you can see is clear.
- RVV 1990, Art. 20–22: general maximum speeds and default speed structure.
- RVV 1990, Art. 34: fog-light rules, including the rear fog-light rule under 50 metres visibility.