National speed limit on dual carriageways.

[Victor M]

When did it become law that dual carriageways without central crash barriers are limited to 60mph.

[Ethel]

Surely it has always been so. With no crash barrier it is not a dual carriageway - it is a two lane single carriageway.

http://www.abd.org.uk/know_your_speed_limits.h tm

[bazmoore]

dual carriageway doesnt need to have a crash barrier a central reservation would suffice

two or more lanes only seperated by road markings is classed as single carriageway as far as national speed limit concerned 60 mph for cars 40mph for hgvs.

[Aprilis]

A road is a dual carriageway if the lanes travelling in opposite directions are separated by a central reservation or crash barrier. If they are not separated in this way the road is a single carriageway.

Note that the national speed limit on dual carriageways only applies when there are no other speed limit signs shown to the contrary. If the national speed limit sign (white circle, black diagonal stripe) is shown, then the speed limit is 70mph.

[gazzam]

Im a driving instructor what Aprilis says is bang on