National speed limit sign?

Question

Why is the national speed limit sign just a white circle with a black line through it and other speed limits are numbers such as 30, 40 and 50? Why did they decide not to just put a 70 sign or in some cases a 60 sign?

Answer 1

So that if the national speed limit is changed the thousands of signs don't have to be replaced.

Answer 2

The national speed sign means for that type of road for your vehicle. when you see it it does not mean you can drive at 70mph The National speed limit sign means for vehicles with no individual restriction, 60 on single carriageways and 70 on dual carriageways and motorways.

Also some vehicles have restrictions on certain roads, it basically means drive within the national speed limit for the road you are on and the vehicle you are driving.

Answer 3

It's a throw back to the days before we had national speed limits. The white circle with the black diagonal line actually means a speed de-limited road, i.e. you could do whatever speed you wanted on that road.

The indroduction of speed limits in 1965 effectively made these signs obsolete but rather than replace them their meaning altered to mean maximum speed limit.

Answer 4

because it depends whether the road is a single or dual carriage way and what type of vehicle your in because on a dual carriage way on the national speed limit for a car is 70 where as for a lorry its slower (60 I think) therefore if you had the speed there would be a few signs for the one roadfor different vehicles...

basically for the reasons above the national speed limit sign is just clearer for everyone :)

Hope this has helped :)

Answer 5

The white circle, black diagonal stripe sign means that the maximum speed limit applie for that type of road. I.E. 70mph on a motorway or dual carriageway, 60mph on a single carriageway.

Answer 6

There is no national speed limit in the U.S.  There used to be, set at 55, and that was the maximum speed on all interstate highways for about ten years.  It is no more.

Answer 7

Nevada California 100 is not a problem and I've done it and still be passed like I was walking

Answer 8

This sign is used as the maximum speed limit under certain road design and condition, with this sign urban, semi-built up can be anything from 50 to 60 mph to  unless otherwise stated. Dual carriageways are given these B&W signes national speed limit usually 60 MPH, motorways are again with the same sign and are 70 MPH, unless otherwise stated due to weather and, or road conditions.

Read the highway code, it's all there.

Answer 9

Originally, there wasn't a national speed limit (obviously you're too young to know that). Once you were out of the local speed limit, you could go as fast as you liked. (Aah, the good old days.....)

The sign you refer to meant "End of speed limit". When the national speed limit was introduced, they just let the sign take on the meaning it does now, instead of spending millions replacing all the signs.

That's us British for you - we make things more complicated than they need to be. They should've just called it the "End of Local Speed Limit" sign.

Answer 10

the same sign is used for both dual and single track carriageways The number of carriageways denote the meaning so saving time and money.

perhaps some people who have provided answers should read the highway code!

Answer 11

Depends where you are. In Scotland they use 60 & 70 mph signs that  look like normal speed limit signs. Seems to work better, many drivers south of the border don't seem to understand the national speed limit sign & drive at 40 mph on country lanes which really pees  me off.