Dual Carriageways
Dual carriageways are efficient.

Dual Carriageways
Dual Carriageways are safer than single carriageway roads

Dual Carriageways
General rules and information about Dual Carriageways

Dual carriageways not only offer a safer means of travelling distances. Dual carriageways usually have higher speed limits enabling us to travel longer distances in a shorter time. Sounds great. Be careful though because when things go wrong on dual carriageways at higher speeds they go wrong quickly. Always make certain that you maintain effective observations and a suitable clearance between yourself and the vehicle ahead on a dual carriageway.

If you are travelling along the driving lane (left lane) of the dual carriageway and see someone ahead who wishes to enter the dual carriageway from a junction it is considered courteous to change lanes if it is safe to do so to enable the other vehicle to access the dual carriageway. If it is not safe to do this then remain in your normal drive position on the dual carriageway. The traffic merging onto the dual carriageway should give way to you when they reach the give way lines. You should be aware that they do not always do this.

Dual Carriageway - Signs for Dual Carriageways

The beginning and end of every dual carriageway should be signposted. The signs that you see below will become very familiar to you on dual carriageways.
This signpost advises drivers that they have to perform a compulsory left turn and that they are joining a dual carriageway. This sign advises drivers that there is a dual carriageway ahead. This information is useful because it allows you to plan ahead as to whether you want to consider overtaking a slower vehicle when you reach the dual carriageway. This signpost advises drivers that they have to give way at the end of the road and that the new road is a dual carriageway. They will be able to turn either left or right onto the dual carriageway.
This sign states that traffic must pass on the left and will be situated at the beginning of a dual carriageway on the central reservation. This may seem obvious but in an area where you are unfamiliar it is nice to have confirmation at the start of the dual carriageway. You would not want to drive the wrong way along a dual carriageway. The National Speed Limit sign. This is usually found at the beginning of dual carriageways and the national speed limit for a dual carriageway is at present seventy miles per hour. Dual carriageways are not always rated at the national speed limit. Often in densely populated areas the speed for a dual carriageway is lower. Dual Carriageway Ends. This sign is at the end of every dual carriageway. Once you pass it there is likely to be oncoming traffic and you may no longer feel as safe to overtake as you did on the dual carriageway.

The signs above are not the only ones that you may find at dual carriageways but they are the most common ones.

Dual Carriageways - Two Second Gap

Speed is the obvious difference between dual carriageways and normal single carriageway roads. On dual carriageways the distance between vehicles is still measured by the two second gap. Because of the higher speeds achievable on dual carriageways the distance covered in two seconds is greatly increased. On Dual Carriageways always be aware of your two second gap.

Dual Carriageways - Separate procedures

If you are asked to turn right at a junction on a dual carriageway then your instructor will expect you to perform two separate procedures.

  1. Changing lanes is a separate procedure on a dual carriageway
  2. A separate right turn procedure is required on a dual carriageway at the junction

It is important that a distinction is shown between the two procedures on dual carriagewaysso make sure that you cancel the signal from the lane change procedure before you begin the mirror checks and re-apply the signal for the right turn procedure.

Dual Carriageways - In built up areas

Dual Carriageways in built up areas are often restricted to lower speed limits because of the amount of traffic that needs to use them simultaneously.

In built up areas parking is sometimes allowed at certain restricted times of day on the side of dual carriageways. The times at which parking is allowed will be displayed on small signs at the side of the dual carriageway.

Use the overtaking lane of dual carriagewaysto pass the stationary vehicles of course but do not forget that once you are past the last stationary vehicle you must return to the near side lane. If you can see more vehicles parked on the near side lane further down the dual carriageway then remain in the overtaking lane until you have completed the overtaking manoeuvre. You do not want to change lanes any more times than necessary on a dual carriageway.

It may not be necessary to change lanes on a dual carriageway when moving around a stationary vehicle. If the stationary hazard is only slightly on the road (two wheels parked on the pavement and two on the road for example) and can be passed either without crossing the white line or only just crossing it a little then a stationary/slow hazard procedure will suffice.

Dual Carriageways - in open areas

The national speedlimit usually applies to dual carriageways in open areas. The higher speed limit allows the traffic to move between urban areas much more efficiently and safely then they otherwise would using single carriageway roads.

Because of the higher speeds that are attainable on dual carriageways the accidents when they do happen have the potential to be very serious indeed. Always be aware of your two second gap.

Dual Carriageways

Dual Carriageways - Entering a Dual Carriageway

Dual Carriageways - Entering a Dual Carriageway from a side road turning left

This is basically the same as an emerge to the left. There are some special considerations to take into account when emerging onto a dual carriageway though though.

These signs tell you that you are approaching a dual carriageway and that you have to turn left.

All of the traffic on the dual carriageway will be approaching from your right but it is still important that you check to the left. There may be pedestrians crossing the road or the traffic may be stationary on the dual carriageway for some reason. In both cases it is good to know that you are safe before you move out.

While observing to the right do not just consider the near side driving lane. Traffic in the overtaking lane of the dual carriageway may well be changing back into the driving lane. Observe effectively until there is a suitable gap before moving off.

When you do emerge stay in the driving (left) lane unless you are near to a junction where you need to turn right. We should always drive in the near side lane unless overtaking something or turning right.

Dual Carriageways - Entering a Dual Carriageway from a side road turning right

If you find yourself approaching a dual-carriageway at the end of a road and your instructor tells you to turn right at the end of the road then they want you to turn right across the dual carriageway.

This signage tells us that we are approaching a dual carriageway and that we have to give way to traffic already on the dual carriageway.  There is no turning restrictions indicated by these signs so we may turn either left or right.

You are going to have to stop and assess the situation from the side of the dual carriageway.

The width of the central reservation of the dual carriageway is very important. You have to make the decision whether or not it would be safe enough for you to stop in the central reservation if you got half way across the dual carriageway and were unable to complete the manoeuvre onto the other side of the dual carriageway.

In either of the above circumstances it pays to remember that the gap in the traffic must be large enough that you do not affect the speed of the other road users because of your actions. You will read this in other places. It is true in all places.

Turning right either across or from a dual-carriageway can be a dangerous manoeuvre if not completed carefully.

Dual Carriageways - Entering a Dual Carriageway from an entrance ramp

Entering a dual carriageway from an entrance ramp could not be easier.

As you move along the ramp you have to perform a lane change procedure to the right to access the dual carriageway.

If it is not possible to enter the dual carriageway because of traffic conditions then you have to wait behind the give way lines until it is safe to enter the dual carriageway.

Whilst driving with others you will have seen many people enter a dual carriageway without even considering giving way to traffic already on the dual carriageway. This is becoming increasingly common but is very dangerous.

Dual Carriageways

Dual Carriageways - Leaving a Dual Carriageway

Dual Carriageways - Leaving a Dual Carriageway into a side road on the left

Check thoroughly and well in advance to find how far away traffic behind you is and how much faster than you they may be travelling.

Indicate your intentions early to give road users on the dual carriageway behind planty of notice that you intend to leave the dual carriageway. Begin to reduce speed early.

You have to slow down enough to make your turn from the dual carriageway safely, bearing in mind that there may be a meet situation straight away in the new road.

Dual Carriageways - Leaving a Dual Carriageway into a side road on the right

If you are driving along a dual-carriageway and need to turn right into a side road then you first have to take the right hand lane using the changing lanesprocedure.

Now you need to begin a normal right turn procedure; making sure that you do not start to indicate too early if there are any gaps in the central reservation of the dual carriageway before the one that you intend to take.

You will approach the gap in the central reservation of the dual carriageway slowly and judge any gaps in the oncoming traffic. If it is possible to take a lower gear and go straight across, completing the turn then that is the favourite. Your instructor does not want to sit out there in the middle of the dual carriageway any more than you do. If it is necessary to stop please make sure that you stop before the give way line. It is very dangerous for you to have the front of your car sticking out onto the oncoming carriageway. Do not move away until you are sure that you can completely cross both of the oncoming traffic lanes without affecting the oncoming traffic at all.

Dual Carriageways - Leaving a Dual Carriageway using an exit ramp

As you approach the exit of the dual carriageway that your instructor wants you to take they will say, "I would like you to leave the road at the next exit please."

These are the hundred yard markers that you would see on approach to the exit ramp on a dual carriageway.

Ahead of you on the left of the dual carriageway you should see the first of three markers illustrated on the left of this column. The stripes each indicate a distance of one hundred yards from the exit.

At the three hundred yard marker you shoud perform your mirror checks and apply the indicator.

Maintain a constant speed between the three and one hundred yard markers.

At the one hundred yard marker take your foot from the gas pedal but do not press the brake pedal.

As you begin to cross the line at the exit of the dual carriageway, now is the time to begin braking. You should brake as necessary and select a lower gear as necessary for whatever road or junction you are now faced with.

The above procedure may need to be varied a little because people do cut in front of other drivers when they are leaving dual carriageways. They should not do it, but this never stops them. Be careful out there.

Dual Carriageways

Dual Carriageways - I hope that this tutorial has helped you to further your understanding of Dual Carriageways

Dual Carriageways are safe roads - Lets keep Dual Carriageways safe!

Findley's Driving School, School of Motoring