DTT HGV Road Signs — Questions and Answers
Question 1: What does a circular sign with a red border showing a truck silhouette mean?
- No entry for goods vehicles (or vehicles over the weight shown) (Correct answer)
- Truck parking area ahead
- Truck route recommended
- Warning: trucks turning
Correct answer: No entry for goods vehicles (or vehicles over the weight shown)
A circular regulatory sign with a red border and a truck silhouette prohibits entry for goods vehicles. If a weight is shown (e.g., 7.5t), it applies to vehicles exceeding that weight. This is commonly seen in residential areas and on weight-restricted bridges.
Question 2: What does a triangular warning sign showing a steep incline with '10%' indicate?
- A steep hill ahead with a gradient of 10% — select appropriate gear (Correct answer)
- The road width narrows by 10%
- Speed limit of 10 km/h
- 10% of the road is under repair
Correct answer: A steep hill ahead with a gradient of 10% — select appropriate gear
This triangular warning sign indicates a steep hill with a 10% gradient (1 metre rise for every 10 metres of road). Truck and bus drivers should select an appropriate low gear before the descent and avoid over-reliance on brakes.
Question 3: What does a rectangular sign with 'LOW BRIDGE' and a height measurement indicate?
- The maximum height of vehicle that can safely pass under the bridge ahead (Correct answer)
- The depth of water at a ford crossing
- The width restriction ahead
- The height of the road above sea level
Correct answer: The maximum height of vehicle that can safely pass under the bridge ahead
Low bridge signs show the maximum safe clearance height. Drivers of tall vehicles must know their vehicle's height and must not attempt to pass under the bridge if their vehicle exceeds the stated clearance. Bridge strikes are a serious and costly offence.
Question 4: What does a blue circular sign showing a truck and a car side by side (with the truck crossed out) mean?
- No overtaking by heavy goods vehicles (Correct answer)
- Trucks and cars must travel side by side
- Dual carriageway for trucks and cars
- Truck parking next to car parking
Correct answer: No overtaking by heavy goods vehicles
This mandatory sign prohibits overtaking by heavy goods vehicles. It is typically placed on sections of road where truck overtaking manoeuvres would be dangerous or cause excessive traffic delays, such as on long uphill sections.
Question 5: What does a sign showing an axle weight limit (e.g., '8t' with an axle symbol) mean?
- No vehicle with any axle weight exceeding the stated limit may use this road (Correct answer)
- The total vehicle weight must not exceed 8 tonnes
- The road has 8 tonnes of material on it
- Speed limit for 8-tonne vehicles
Correct answer: No vehicle with any axle weight exceeding the stated limit may use this road
An axle weight limit sign restricts individual axle weights, not total vehicle weight. This is different from a gross weight limit. A vehicle might be within the total weight limit but still exceed the axle weight limit, especially if poorly loaded.
Question 6: What does a sign showing a width restriction (e.g., '2.5m' with width indicator arrows) mean?
- The road or structure ahead has a width restriction — vehicles wider than the stated measurement cannot pass (Correct answer)
- The lane is 2.5 metres wide
- You must maintain 2.5 metres between vehicles
- The speed limit is 2.5 times higher than normal
Correct answer: The road or structure ahead has a width restriction — vehicles wider than the stated measurement cannot pass
Width restriction signs indicate that the road, bridge, or structure ahead cannot accommodate vehicles wider than the stated measurement. Drivers must know their vehicle's width including mirrors and any wide loads.
DTT HGV Road Signs
What does a circular sign with a red border showing a truck silhouette mean?