D is for...

D is for... Dual carriageways!

A dual carriageway is a road which has a central reservation to separate the carriageways. They are usually used to link major roads or areas together, and where there is high traffic flow – where two lanes would benefit the traffic to keep traffic moving. Despite the name, some ‘dual carriageways’ have three lanes.

How do you join a dual carriageway?

If you’re emerging from a side road where there is no slip road, emerge as you would like a left turn at a junction. Ensure that you emerge into the left hand lane of the dual carriageway, and you wait for a gap big enough to build up your speed.

If there is a slip road, indicate your intention to join, and use the slip road to adjust your speed to that of the traffic on the dual carriageway. Look for a gap in the traffic, and then merge into the left hand lane. Consider a quick sideways glance to check that there are no vehicles next to you, but also use your mirrors effectively to see the position of the vehicles on the main dual carriageway.

Once you have joined, remember to cancel your indicators, and continue to build up your speed to match the speed of other vehicles.

If other vehicles are trying to join the dual carriageway whilst you are already on it, follow these tips –

- Don’t try to race them whilst they’re on the slip road

- Look well ahead, if there are several vehicles trying to join, be prepared to adjust your speed

- Show consideration for traffic joining, and if it’s safe to do so, change lanes to give the joining traffic space

- Take extra care if the dual carriageway curves, as vehicles on the slip road may have difficulty seeing vehicles on the dual carriageway

Whilst on the dual carriageway

Continually reassess the movement of other vehicles, and check your mirrors so you know what’s happening around you. Remember that at high speeds, situations can change rapidly, and effective observations can help you prepare for any sudden developments.