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AF Commercial Driving Theory study materials
AF Commercial Driving Theory study resources

AF Commercial Driving Theory practice questions

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Question 1Road Traffic Rules and Regulations

On a road with a posted speed limit of 80 km/h, what is the maximum speed a heavy goods vehicle over 12 tonnes is generally permitted to travel in most jurisdictions?

  1. 60 km/h Correct answer.
  2. 50 km/h
  3. 80 km/h
  4. 70 km/h

Explanation

Heavy goods vehicles above a set weight threshold are subject to a lower maximum speed than the general limit for light vehicles. In many jurisdictions this reduced limit is 60 km/h on ordinary roads. The posted limit applies to light vehicles, while the lower limit binds the heavy vehicle.

Question 2Road Traffic Rules and Regulations

What is the purpose of a tachograph in a commercial vehicle?

  1. To log fuel consumption for tax purposes
  2. To monitor tyre pressure while driving
  3. To record driving time, rest periods and speed Correct answer.
  4. To measure the weight carried on each axle

Explanation

A tachograph is a recording device that logs driving time, other work, availability and rest periods, as well as vehicle speed and distance. It exists to enforce rules on drivers' hours and rest. It does not measure axle weight, fuel use or tyre pressure.

Question 3Road Traffic Rules and Regulations

When must a driver use hazard warning lights on a moving commercial vehicle?

  1. When reversing into a loading bay
  2. When the vehicle is broken down and obstructing traffic Correct answer.
  3. When driving slowly in a queue of traffic
  4. When parking on a double yellow line for a delivery

Explanation

Hazard warning lights are intended to warn other road users that the vehicle is stationary and causing an obstruction, for example after a breakdown. They should not be used as a substitute for proper signals while driving or parking illegally. Using them during normal reversing or queuing is not their purpose.

Question 4Road Traffic Rules and Regulations

What does a solid white line along the centre of the road normally indicate?

  1. Overtaking is permitted if the road is clear
  2. The line may be crossed to enter a side road
  3. Vehicles must not cross or straddle the line Correct answer.
  4. The lane is reserved for buses only

Explanation

A continuous solid centre line means drivers must not cross or straddle it, generally because visibility or road layout makes overtaking unsafe. It may be crossed only in limited exceptions such as entering premises or a side road where permitted. It does not reserve the lane for any vehicle class.

Question 5Road Traffic Rules and Regulations

What is the minimum legal tread depth for commercial vehicle tyres in most jurisdictions?

  1. 1.6 mm across the central three-quarters of the tread Correct answer.
  2. 2.5 mm across the whole tread width
  3. 3.0 mm across the whole tread width
  4. 1.0 mm across the central three-quarters of the tread

Explanation

The common legal minimum tread depth is 1.6 mm measured across the central three-quarters of the tread around the entire circumference. Tyres below this are illegal and unsafe in wet conditions. The other figures do not match the standard requirement.

Question 6Road Traffic Rules and Regulations

A driver approaching a zebra crossing sees a pedestrian waiting on the pavement. What must the driver do?

  1. Flash headlights and proceed
  2. Continue at the same speed if no one is on the crossing
  3. Slow down and be prepared to stop to let the pedestrian cross Correct answer.
  4. Sound the horn to warn the pedestrian

Explanation

Drivers must give way to pedestrians on a zebra crossing and should slow down and prepare to stop when someone is waiting. Sounding the horn or flashing lights to hurry a pedestrian is inappropriate. Proceeding at speed is unsafe even if the crossing is momentarily clear.

Question 7Road Traffic Rules and Regulations

What is the main rule regarding seat belt use by the driver of a goods vehicle?

  1. Seat belts are optional for drivers of goods vehicles
  2. Seat belts are required only for journeys over 50 km
  3. The driver must wear a seat belt where one is fitted Correct answer.
  4. Seat belts are required only on motorways

Explanation

Where a seat belt is fitted, the driver is legally required to wear it, and this applies to goods vehicles as well. There is no exemption based on road type or journey distance. Passengers must also use belts where provided.

Question 8Road Traffic Rules and Regulations

When may a driver sound the horn of a commercial vehicle?

  1. To express frustration in traffic
  2. To warn other road users of danger Correct answer.
  3. To greet another driver
  4. To signal arrival at a delivery point

Explanation

The horn should be used only to warn other road users of your presence or of danger. It must not be used for greetings, announcements or expressions of annoyance. Its purpose is safety, not communication of convenience.

Question 9Road Traffic Rules and Regulations

A commercial vehicle is involved in a collision that causes injury to a person. What is the driver's first legal duty?

  1. Stop, give details and report the collision to the police Correct answer.
  2. Drive on if the injury appears minor
  3. Continue to the nearest depot and report it
  4. Exchange insurance details only if the other driver asks

Explanation

After a collision causing injury, the driver must stop and provide the required particulars, and report the collision to the police within the legal time limit if details are not exchanged. Leaving the scene is an offence. The seriousness of the injury is not for the driver to judge.

Question 10Road Traffic Rules and Regulations

What is the standard maximum continuous driving period before a qualifying break is required under drivers' hours rules?

  1. 8 hours
  2. 6 hours
  3. 4 hours 30 minutes Correct answer.
  4. 2 hours

Explanation

Under the harmonised drivers' hours rules, a driver must take a break after a maximum of 4 hours 30 minutes of continuous driving. A qualifying break of at least 45 minutes is then required, which may be split under specific conditions. The other periods do not match the rule.

Question 11Road Traffic Rules and Regulations

A driver has driven for 4 hours 30 minutes. Which break arrangement satisfies the standard requirement?

  1. A 15-minute break
  2. No break if the remaining journey is under one hour
  3. A 45-minute break, which may be split into 15 minutes then 30 minutes Correct answer.
  4. A 30-minute break

Explanation

After 4 hours 30 minutes of driving, a break of at least 45 minutes is required. This may be taken as a single 45-minute break or split into a 15-minute break followed by a 30-minute break. Shorter breaks or skipping the break do not comply.

Question 12Road Traffic Rules and Regulations

What does a circular sign with a red border and a number inside generally indicate?

  1. A minimum speed that must be maintained
  2. A recommended speed for the road
  3. A maximum speed limit Correct answer.
  4. A distance to the next town

Explanation

Circular signs with a red border are prohibitory or restrictive signs, and a number inside indicates a maximum speed limit. Minimum speeds are shown on blue circular signs. Recommended speeds and distances use different sign formats.

Question 13Road Traffic Rules and Regulations

A goods vehicle is parked on a road at night on an unlit street. What lighting requirement generally applies?

  1. Parking lights must be shown unless an exemption applies Correct answer.
  2. Only hazard lights are required
  3. No lights are needed if the vehicle is over 12 tonnes
  4. Headlights must be left on full beam

Explanation

Vehicles parked on an unlit road at night must normally show parking lights so they are visible to other road users, unless a specific exemption applies. Hazard lights and full beam are not substitutes for parking lights. Vehicle weight does not remove the requirement.

Question 14Road Traffic Rules and Regulations

When is a driver permitted to cross a continuous white line to overtake a slow-moving agricultural vehicle?

  1. Whenever the road ahead appears clear for 100 metres
  2. Never, under any circumstances
  3. Only where a broken line or specific exception permits it Correct answer.
  4. Whenever the agricultural vehicle is travelling below 30 km/h

Explanation

A continuous white line may only be crossed where a broken line or a specific legal exception allows it. The speed of the vehicle ahead does not create an exception. Visibility alone does not override the marking.

Question 15Road Traffic Rules and Regulations

What is the maximum permitted blood alcohol concentration for a professional driver in jurisdictions with a reduced limit for professionals?

  1. 0.02% or lower Correct answer.
  2. 0.08%
  3. 0.05%
  4. 0.10%

Explanation

Many jurisdictions set a lower blood alcohol limit for professional and novice drivers, commonly 0.02% or effectively zero. The general limit for other drivers is higher. Professional drivers are held to a stricter standard because of the size and risk of their vehicles.

Question 16Road Traffic Rules and Regulations

A driver must make an emergency stop on a motorway hard shoulder. What should the driver do first?

  1. Pull onto the hard shoulder, stop as far left as possible and switch on hazard lights Correct answer.
  2. Reverse along the hard shoulder to the previous exit
  3. Stay in the vehicle in the live lane
  4. Stand behind the vehicle to direct traffic

Explanation

In an emergency, the driver should move onto the hard shoulder, stop as far to the left as possible and use hazard lights to warn others. Occupants should exit on the side away from traffic and wait in a safe place. Remaining in a live lane or standing in the carriageway is dangerous.

Question 17Road Traffic Rules and Regulations

What does a broken white line with long dashes and short gaps on the centre of the road warn of?

  1. A hazard ahead where overtaking should be approached with caution Correct answer.
  2. A cycle lane boundary
  3. A place where parking is permitted
  4. A bus stop clearway

Explanation

Long dashes with short gaps warn of a hazard ahead, such as a junction or bend, and signal that overtaking should be undertaken with caution. They are not lane boundaries for buses or cycles and do not indicate parking permission.

Question 18Road Traffic Rules and Regulations

A driver is directed by a police officer to proceed through a red traffic light. What should the driver do?

  1. Obey the red light and refuse to move
  2. Wait for the light to turn green before moving
  3. Sound the horn and proceed slowly
  4. Follow the officer's direction Correct answer.

Explanation

Directions given by a police officer controlling traffic take precedence over normal signals and signs. The driver should follow the officer's instruction carefully. Ignoring the officer because of the red light could obstruct traffic and is not required.

Question 19Road Traffic Rules and Regulations

What is the purpose of a weighbridge check on a commercial vehicle?

  1. To confirm the tachograph calibration
  2. To test the brake balance
  3. To verify that axle and gross weights are within legal limits Correct answer.
  4. To measure the vehicle's stopping distance

Explanation

Weighbridges determine axle loads and gross vehicle weight to ensure they do not exceed legal limits. Overloading affects braking, stability and road wear and is an offence. Stopping distance, brake balance and tachograph calibration are tested by other means.

Question 20Road Traffic Rules and Regulations

A driver approaches a level crossing where the barrier is raised but the red lights are flashing. What should the driver do?

  1. Drive around the barrier if it is only partly down
  2. Proceed because the barrier is up
  3. Sound the horn and cross quickly
  4. Stop and wait until the lights stop flashing Correct answer.

Explanation

Flashing red lights at a level crossing mean a train is approaching, and the driver must stop and wait even if the barrier is still raised. The barrier may lower shortly after the lights begin. Proceeding or driving around a barrier is extremely dangerous.

Question 21Road Traffic Rules and Regulations

What is the general rule for using a mobile phone while driving a commercial vehicle?

  1. Any phone use is permitted if the vehicle has a tachograph
  2. Hand-held use is allowed while stationary in traffic
  3. Hand-held use is prohibited, and hands-free use must not distract the driver Correct answer.
  4. Phone use is allowed at speeds below 30 km/h

Explanation

Hand-held mobile phone use while driving is prohibited, and even hands-free use is an offence if it causes the driver to lose proper control. Being stationary in traffic or having a tachograph does not create an exception. Safe control of the vehicle is the governing principle.

Question 22Road Traffic Rules and Regulations

A driver's tachograph record shows insufficient daily rest. Who is responsible for ensuring compliance with drivers' hours rules?

  1. Only the transport manager
  2. Only the vehicle manufacturer
  3. Only the driver
  4. Both the driver and the operator Correct answer.

Explanation

Responsibility for drivers' hours compliance is shared: the driver must manage their own driving and rest, and the operator must plan schedules and monitor records to prevent infringements. The manufacturer has no role in operational compliance. Placing responsibility on only one party is incomplete.

Question 23Road Traffic Rules and Regulations

A vehicle's maximum authorised mass is 18 tonnes, but a weighbridge shows a gross weight of 19.5 tonnes. What is the legal position?

  1. The vehicle is overloaded and must not proceed until the load is reduced Correct answer.
  2. It is acceptable if the excess is under 10 percent
  3. It is permitted on motorways only
  4. It is permitted if the driver reduces speed by 20 km/h

Explanation

Exceeding the maximum authorised mass is an offence regardless of the percentage over, and the vehicle should not continue until the excess load is removed. There is no speed-based or road-type exemption. Overloading affects braking and stability and increases road damage.

Question 24Road Traffic Rules and Regulations

A driver is planning a journey that requires two reduced weekly rests in succession. What is the correct approach under drivers' hours rules?

  1. Two reduced weekly rests may be taken back to back without compensation
  2. A reduced weekly rest may only be taken abroad
  3. Reduced weekly rests are not permitted for goods vehicles
  4. A reduced weekly rest must be compensated by an equivalent period attached to another rest Correct answer.

Explanation

A reduced weekly rest must be compensated by an equivalent period of rest added to another rest period, and rules limit how reduced rests may be taken consecutively. Back-to-back reduced rests without compensation breach the rules. There is no blanket prohibition or geographic restriction.

Question 25Road Traffic Rules and Regulations

A load overhangs the rear of a goods vehicle. What requirement generally applies in daylight?

  1. The end of the projection must be made clearly visible, often with a marker Correct answer.
  2. No marking is required if the overhang is under 2 metres
  3. Only the hazard lights need to be switched on
  4. The vehicle may not be driven at all

Explanation

Where a load projects beyond the vehicle, the end of the projection must be made clearly visible to other road users, typically with a marker or flag by day and reflective marking or light at night. The vehicle may still be driven if the load is properly secured and marked. Hazard lights are not the required marking.

Question 26Road Traffic Rules and Regulations

What is the general rule for a driver approaching a roundabout when the intended exit is the first one to the left?

  1. Signal left on approach and keep to the left-hand lane Correct answer.
  2. Stay in the middle lane and signal only after passing the first exit
  3. Signal right and move to the right-hand lane
  4. Do not signal at any point until leaving the roundabout

Explanation

When taking the first exit to the left, the driver should signal left on approach and approach in the left-hand lane, maintaining the signal until the exit is taken. This informs other road users of the intention to leave at the first opportunity.

Question 27Road Traffic Rules and Regulations

A commercial vehicle is travelling on a dual carriageway with a national speed limit. What is the maximum speed for a goods vehicle not exceeding 7.5 tonnes maximum authorised mass?

  1. 60 mph Correct answer.
  2. 70 mph
  3. 40 mph
  4. 50 mph

Explanation

On a dual carriageway subject to the national speed limit, goods vehicles with a maximum authorised mass not exceeding 7.5 tonnes are restricted to 60 mph. The higher figure of 70 mph applies only to cars and motorcycles.

Question 28Road Traffic Rules and Regulations

A driver is waiting at a junction and a pedestrian has stepped onto a zebra crossing from the opposite side. What must the driver do?

  1. Edge forward slowly to encourage the pedestrian to hurry
  2. Sound the horn to warn the pedestrian
  3. Wait until the pedestrian has completely crossed and left the crossing Correct answer.
  4. Proceed if there is enough space to pass behind the pedestrian

Explanation

Once a pedestrian has stepped onto a zebra crossing, the driver must give way and wait until the pedestrian has cleared the crossing. Passing behind a pedestrian on the crossing is not permitted.

Question 29Road Traffic Rules and Regulations

What is the general rule about using hazard warning lights on a moving commercial vehicle?

  1. They may be used only when the vehicle is being towed
  2. They may be used whenever the driver wishes to warn of any hazard ahead
  3. They may be used when the vehicle is moving slowly on a motorway in a traffic queue Correct answer.
  4. They may be used only when the vehicle is stationary

Explanation

Hazard warning lights may be used while moving on a motorway or unrestricted dual carriageway to warn drivers behind of a hazard or traffic queue ahead. At other times they should normally be used only when the vehicle is stationary.

Question 30Road Traffic Rules and Regulations

A driver intends to turn right into a side road. What is the correct procedure regarding oncoming traffic?

  1. Give way to oncoming traffic that is going straight ahead Correct answer.
  2. Turn first if the driver has already entered the junction
  3. Turn across the path of oncoming vehicles that are signalling left
  4. Proceed if the oncoming vehicle is a bicycle

Explanation

When turning right, a driver must give way to oncoming traffic that is going straight ahead or turning left, unless signs or signals indicate otherwise. The driver should wait for a safe gap before completing the turn.

Question 31Road Traffic Rules and Regulations

What is the national speed limit for a goods vehicle with a maximum authorised mass over 7.5 tonnes on a single carriageway road?

  1. 30 mph
  2. 60 mph
  3. 50 mph
  4. 40 mph Correct answer.

Explanation

On a single carriageway subject to the national speed limit, goods vehicles over 7.5 tonnes maximum authorised mass are restricted to 40 mph. This lower limit reflects the greater stopping distance and weight of such vehicles.

Question 32Road Traffic Rules and Regulations

A driver is approaching a junction where the traffic lights are out of order. What should the driver do?

  1. Treat the junction as uncontrolled and proceed with caution Correct answer.
  2. Wait for a police officer to direct traffic
  3. Follow the vehicle in front without checking
  4. Proceed as if the lights were green

Explanation

When traffic lights are not working, the junction should be treated as uncontrolled. Drivers must proceed with caution, giving way as necessary and observing any temporary signs or police directions.

Question 33Road Traffic Rules and Regulations

What does a circular sign with a blue background and a white arrow pointing straight ahead mean?

  1. No entry for vehicles
  2. Give way to oncoming traffic
  3. One-way traffic ahead
  4. Ahead only Correct answer.

Explanation

A blue circular sign with a white arrow is a mandatory instruction sign. An arrow pointing straight ahead means that traffic must proceed ahead only.

Question 34Road Traffic Rules and Regulations

A driver is overtaking a cyclist on a narrow road. What is the recommended minimum passing distance in good conditions?

  1. At least 1.5 metres Correct answer.
  2. At least 1 metre
  3. At least 0.5 metre
  4. At least 2 metres

Explanation

When overtaking a cyclist, drivers should allow at least 1.5 metres of clearance in good conditions, and more at higher speeds. This gives the cyclist room to avoid hazards such as potholes.

Question 35Road Traffic Rules and Regulations

What is the legal requirement for a driver who intends to change lanes on a motorway?

  1. Move first and signal afterwards
  2. Rely on other drivers to make room
  3. Signal and check mirrors and blind spots before moving Correct answer.
  4. Sound the horn before changing lanes

Explanation

Before changing lanes, a driver must use mirrors and check blind spots, then signal in good time to warn other road users. The manoeuvre should only be carried out when it is safe to do so.

Question 36Road Traffic Rules and Regulations

A driver is approaching a steep downhill section in a laden goods vehicle. What is the correct technique?

  1. Switch off the engine to reduce speed
  2. Use a lower gear to assist braking Correct answer.
  3. Rely solely on the footbrake
  4. Select neutral to save fuel

Explanation

On a long or steep downhill gradient, a lower gear should be selected to use engine braking and prevent the brakes from overheating. The footbrake should be used carefully and not continuously.

Question 37Road Traffic Rules and Regulations

What is the general rule for using a bus lane during its hours of operation?

  1. Goods vehicles may use it for loading
  2. Any vehicle may use it if no bus is present
  3. Only buses and authorised vehicles may use it Correct answer.
  4. Motorcycles may always use it

Explanation

During the times shown on the signs, a bus lane may only be used by buses and other vehicles authorised by the signs, such as taxis or cycles where indicated. Other vehicles must keep out.

Question 38Road Traffic Rules and Regulations

A driver is parking a goods vehicle on a road at night in a built-up area with street lighting. What lighting must be shown?

  1. At least headlights
  2. No lights are required
  3. At least parking lights Correct answer.
  4. Hazard warning lights only

Explanation

On a road with street lighting in a built-up area, a parked goods vehicle must show parking lights at night unless an exemption applies. Parking lights make the vehicle visible to other road users.

Question 39Road Traffic Rules and Regulations

What is the maximum permitted width of a vehicle, including load, for general use on public roads without special authorisation?

  1. 3.5 metres
  2. 4.0 metres
  3. 2.55 metres Correct answer.
  4. 2.9 metres

Explanation

The general maximum width for a vehicle, including any load, is 2.55 metres. Wider vehicles require special authorisation and may be subject to notification requirements.

Question 40Road Traffic Rules and Regulations

A driver is involved in a collision where damage is caused to another vehicle but no one is injured. What must the driver do?

  1. Leave a note only if the owner is present
  2. Stop and exchange details with the other party Correct answer.
  3. Drive on if the damage is minor
  4. Report the incident only if asked to do so

Explanation

After a collision causing damage, the driver must stop and provide their name, address and vehicle details to the other party. If details cannot be exchanged, the incident must be reported to the police within the required time.

Question 41Road Traffic Rules and Regulations

What is the purpose of a vehicle's tachograph record?

  1. To log maintenance checks
  2. To record driving times and rest periods Correct answer.
  3. To record fuel consumption
  4. To monitor engine temperature

Explanation

A tachograph records driving time, other work, availability and rest periods. It is used to enforce drivers' hours and working time rules.

Question 42Road Traffic Rules and Regulations

A driver is planning a journey that requires two consecutive reduced weekly rests. What is the correct approach under the drivers' hours rules?

  1. Reduced weekly rests are only allowed in alternate weeks
  2. A reduced weekly rest must be followed by a full weekly rest Correct answer.
  3. Two reduced weekly rests may be taken consecutively
  4. Two reduced weekly rests are allowed if compensated

Explanation

Under the drivers' hours rules, a reduced weekly rest must be compensated for and must be followed by a full weekly rest in the next week. Two reduced weekly rests cannot be taken consecutively.

Question 43Road Traffic Rules and Regulations

What is the general rule for a driver who wishes to use a hand-held mobile phone while driving?

  1. It is prohibited while driving Correct answer.
  2. It is permitted if the call is brief
  3. It is permitted if using a hands-free kit
  4. It is permitted if the vehicle is stationary in traffic

Explanation

Using a hand-held mobile phone or similar device while driving is prohibited. This includes when stationary in traffic, except in limited circumstances such as safely parked.

Question 44Road Traffic Rules and Regulations

A driver is approaching a red traffic light but a police officer signals the driver to proceed. What should the driver do?

  1. Wait for the light to turn green
  2. Obey the red light and stop
  3. Sound the horn to confirm
  4. Obey the police officer and proceed Correct answer.

Explanation

Directions given by a police officer take precedence over traffic lights. The driver should follow the officer's signal, proceeding only when it is safe to do so.

Question 45Road Traffic Rules and Regulations

What is the maximum permitted height of a vehicle, including load, for general use on public roads without special authorisation?

  1. 5.0 metres
  2. 5.5 metres
  3. 4.0 metres Correct answer.
  4. 4.5 metres

Explanation

The general maximum height for a vehicle, including load, is 4.0 metres. Vehicles exceeding this height require special authorisation and may be subject to route restrictions.

Question 46Road Traffic Rules and Regulations

A driver is towing a trailer and the combination exceeds 7 metres in length. What additional requirement applies?

  1. The trailer must have a breakaway cable
  2. The trailer must be fitted with a rear marking plate Correct answer.
  3. The trailer must have a reversing light
  4. A secondary coupling must be used

Explanation

A trailer forming part of a combination exceeding 7 metres in length must display a rear marking plate to warn other road users of its size. This improves visibility and safety.

Question 47Road Traffic Rules and Regulations

What is the general speed limit for a goods vehicle in a built-up area with street lighting, unless signs indicate otherwise?

  1. 20 mph
  2. 50 mph
  3. 30 mph Correct answer.
  4. 40 mph

Explanation

In a built-up area with street lighting, the general speed limit is 30 mph unless signs indicate a different limit. This applies to goods vehicles as well.

Question 48Road Traffic Rules and Regulations

A driver is approaching a zebra crossing where a pedestrian is waiting on the pavement. What must the driver do?

  1. Sound the horn to warn the pedestrian
  2. Continue at the same speed
  3. Give way to the pedestrian Correct answer.
  4. Flash headlights to signal the pedestrian to cross

Explanation

At a zebra crossing, the driver must give way to a pedestrian waiting to cross. The driver should slow down and be prepared to stop.

Question 49Road Traffic Rules and Regulations

What is the general rule for using fog lights on a commercial vehicle?

  1. They may be used whenever visibility is reduced
  2. They may be used in heavy rain
  3. They may be used only when visibility is seriously reduced, generally below 100 metres Correct answer.
  4. They may be used at night instead of headlights

Explanation

Fog lights should only be used when visibility is seriously reduced, generally when the driver cannot see more than 100 metres. They must be switched off when visibility improves to avoid dazzling others.

Question 50Road Traffic Rules and Regulations

A goods vehicle driver is travelling on a road where a speed limit sign shows a lower limit than the national limit for that road type. Which limit applies to the driver?

  1. The limit shown on the sign, because posted limits override the national limit Correct answer.
  2. The limit shown on the sign only during the hours of darkness
  3. The national limit for that road type, because goods vehicles follow national limits
  4. The national limit, unless the sign also shows a goods vehicle symbol

Explanation

Posted speed limit signs set the legal maximum speed for that stretch of road and take precedence over the national limits that would otherwise apply to the road type. A goods vehicle driver must therefore obey the lower figure shown on the sign. National limits only apply where no lower limit is signed.