Mistake 1: Choosing the wrong speed based on the situation

"Outside built-up areas, express road, 2x2 lanes... 90 km/h? 120? 70?"

The permitted speed depends not only on the type of road, but also on the region. In Flanders, outside built-up areas 70 km/h applies on ordinary roads. In Wallonia it is 90 km/h. In Brussels, 30 km/h is the standard within built-up areas — not 50 km/h as many candidates think. On express roads with two directions separated by a central reservation, different rules apply than on ordinary roads. If you do not take the regional context into account, you quickly make the wrong choice. Moreover, the maximum speed is the ceiling, not the recommended speed. In rain, fog or traffic congestion, a lower speed is mandatory.

How do you avoid this?

Learn the speed limits by region off by heart: Flanders (70), Wallonia (90), Brussels (30 in built-up areas as standard). For every speed question, also look at the road type, the infrastructure and the conditions.

Mistake 2: Not paying attention to supplementary plates and additional information

"Oops, I didn’t see that supplementary plate."

Another typical stumbling block: missing extra information on or under traffic signs. You recognise the main sign but ignore the supplementary plate indicating that the prohibition also applies to you — and not only to lorries. Or you miss the zone sign showing that the rule applies to the entire area and not just on the spot. In the exam, these are exactly the small elements that make the difference between right and wrong. A zone sign (such as zone 30) applies until the 'end of zone' sign, even without repetition after every junction. A normal speed limit sign (C11) applies until the next junction or a new sign.

How do you avoid this?

Train yourself to always analyse the whole sign: the main sign and the supplementary plate. Ask yourself: is this a zone sign or a normal sign? Who does it apply to? Also look at the background of the image — signs in the background are at least as relevant.

Mistake 3: Confusing a bus lane with a reserved lane

"Can I drive here to turn off, or not?"

Sometimes a question seems to be about something simple — a lane for buses. But then the difference lies in the road markings and the sign. A bus lane (marked with the word 'BUS' on the road surface) with a broken white line: you may temporarily drive on it to turn off. A reserved lane (marked with the F17 sign — a white sign with a blue bus) with a solid white line: in principle you may not drive on it, except to cross it at a junction. That difference is subtle but is deliberately tested.

How do you avoid this?

Remember the difference: broken line = temporarily driving on it is allowed to turn off. Solid line + F17 sign = reserved lane, do not drive on it. Always pay attention to both elements at the same time.

Mistake 4: Misjudging priority at zebra crossings

"He stopped… so could I overtake?"

Right-of-way rules at zebra crossings are systematically misjudged. Suppose the car in front of you slows down or stops. Can you overtake if there is no pedestrian on the zebra crossing? The answer is no. As soon as another driver slows down or stops for a zebra crossing, you are also required to be extra cautious — in that case you may not overtake that driver. This also applies if you do not see a pedestrian: someone may be about to step onto the crossing. The safety of pedestrians always takes priority.

How do you avoid this?

For every question about a zebra crossing: if a driver in front of you slows down or stops, overtaking is prohibited. Even if you do not see a pedestrian. The exam tests whether you understand the safety logic, not just the literal rule.

Mistake 5: Underestimating stopping and braking distances

"I thought the stopping distance at 100 km/h was about 50 metres..."

When it comes to stopping distance or braking distance, many candidates guess. The actual distances are higher than most people expect. Stopping distance = reaction distance + braking distance. With an average reaction time of 1 second and a dry road surface, the GOCA reference figures are: 50 km/h ≈ 30 metres, 70 km/h ≈ 45 metres, 90 km/h ≈ 70 metres. On wet roads, these distances are significantly higher. At 100 km/h, the stopping distance is already well over 50 metres — anyone answering 'about 50 metres' is way off. For a safe following distance, use the rule of thumb: speed divided by 2 (at 120 km/h = 60 m, at 90 km/h = 45 m).

How do you avoid this?

Learn the GOCA stopping distances off by heart: 50 km/h ≈ 30 m, 70 km/h ≈ 45 m, 90 km/h ≈ 70 m. Also remember the rule of thumb for following distance: speed ÷ 2. On a wet road surface, the stopping distance is always longer — this is deliberately stated in exam questions.

Speed

Stopping distance (dry)

Safe following distance

50 km/h

≈ 30 metres

25 metres

70 km/h

≈ 45 metres

35 metres

90 km/h

≈ 70 metres

45 metres

120 km/h

≈ 108 metres

60 metres

⚠ Remember: stopping distances are ALWAYS higher than you think

At 100 km/h, the stopping distance is already more than 50 metres. Anyone who chooses 'less than 50 metres' makes a mistake. On a wet road surface, all distances are significantly longer. Conditions in an exam question are never mentioned by accident.

Practise this kind of question with RAPP

With RAPP, you practise the category B theory test at GOCA exam level. You get realistic scenario questions, direct explanations for every mistake and targeted practice sessions for your weakest topics. That way, you spot the pitfalls before you encounter them in the real exam.

What are the 5 most common mistakes on the category B theory test?

The 5 most common mistakes are: choosing the wrong speed because you forget the region, missing supplementary plates and zone signs, confusing a bus lane with a reserved lane, overtaking at a zebra crossing when the car in front stops, and underestimating stopping distances.

What is the stopping distance at 90 km/h?

According to the GOCA reference figures, the stopping distance at 90 km/h is about 70 metres on a dry road surface. On a wet road surface, it is significantly longer. The stopping distance consists of reaction distance (±27 m at 90 km/h) and braking distance.

Can I overtake if there is no pedestrian on the zebra crossing?

No. If the driver in front of you slows down or stops for a zebra crossing, you may not overtake them — even if you do not see a pedestrian. Someone may be about to step onto the crossing.

What is the difference between a bus lane and a reserved lane?

A bus lane with a broken white line may be entered temporarily to turn off. A reserved lane (F17 sign) with a solid white line may not be driven on — you may only cross it at a junction.

How do you calculate the safe following distance?

The rule of thumb is: speed divided by 2. At 120 km/h = 60 metres, at 90 km/h = 45 metres, at 50 km/h = 25 metres.

Which speed limit applies within the built-up area in Brussels?

In Brussels, 30 km/h is the standard for the entire built-up area — unless signs permit a higher speed. In Flanders and Wallonia, the standard is 50 km/h.