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  • Emma Hallett

How do you tell the difference between a slip road and a dedicated lane when joining a dual carriage

I found recently a few people are struggling when joining a dual carriageway as they are unsure if it is a slip road or a dedicated lane and therefore don’t know how to deal with it. This problem can also present on a motorway. There are differences in the way you deal with them which I will briefly cover then we’ll go through how to tell them apart.

Slip roads:

  • You will use this to build up speed.

  • You will need to merge in with traffic already on the carriageway.

  • There is a broken line between you and the carriageway which means ‘give way’ so if it is unsafe to join you will need to be prepared to stop at the end of the slip road.

  • You will need to signal to inform others that you are intending to move out.

  • Others will try to make space for you by changing lanes or their speed.

Dedicated lanes:

  • You are joining the carriageway as a new lane.

  • You do not need to signal or look for gaps in traffic.

  • You will not need to ‘give way’.

  • No one will need to make space for you.

Generally when you are joining using a slip road you will not have a sign although occasionally there will be a warning sign. If you do not see a sign proceed as you would for a slip road. It may be a left turn, i.e. little or no slip road, but if it is you follow the same procedure but are more likely to stop.

If you are joining with a dedicated lane there will be a sign similar to the green one above (it may have a different number of lanes).

Also look for the road markings, slip roads have a ‘dotted’ give way line whereas dedicated lanes have a normal lane divider. Also check the cat’s eyes if possible, a slip road will have red then green between you and the carriageway, dedicated lanes have red then white.

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