Safe Speed Forums

Driving for 200 miles yesterday and sticking to the speed limits, I began to wonder how traffic engineers decide what speed limit to apply to a given piece of road. A classic was the A614 between Bridlington and Driffield. On the section from Haisthorpe to Burton Agnes there is a 40 mph limit. It is a wide (20 feet) road passing through little hamlets and open country. The latter bits are the same 40 mph which seems unnecessarily slow for the prevailing conditions. Perhaps a local forum member can enlighten me why this speed limit is there rather than say 50 between the hamlets?
A classic around here is on the A1044/ B1380 from Yarm to Hemlington: 50 mph on an urban section followed by NSL on a twisty section with steep gradients and a narrow bridge at the bottom. Followed by 50 again on another much straighter flat section, followed by NSL on another twisty section with no overtaking. Bonkers, IMHO.

Where I live, they appear to do it by examining the entrails of goats sacrificed at the full moon.

Many of the roads round here are limited to 40mph - they're reasonably wide, have good surfaces and reasonable sight-lines... Yet we have some beautiful anomalies, for example: all the roads limited to 40 have houses along them, yet there's one quite long stretch of road that's 30. It's otherwise indistinguishable from the others except it has no houses and nice wide grass verges. It has one turning off it, but so do most of the 40s. There appears to be no logical reason whatsoever for the limit being lower. Except; part way along there's a thick bush that the council never seems to trim with quite as much enthusiasm as the rest - guess where the local plod sets up his radar-trap? The whole area is very popular with tourist, and it's remarkable how often the radar comes out on a nice sunny day. Probably quite a nice little earner.

Pogo,

Are you talking about the Ironbridge area?

I'm in Telford BTW.

Yes... "Blists Hill (Legges Way) v "Cuckoo Oak" and assorted roads round it.
We'll have to have a pint and set the world to rights!

Had an idea that's where you were referring to. I just wonder if it isn't something to do with the clustering of tourist sites in that area and the liklihood of meeting someone pulling out or driving aimlessly around looking for places.

Maybe.. But all the feeder roads to it are urbanised and 40.. Seems illogical.

There are a few systems that are well designed from the top down, but most systems carry around large amounts of political and legacy baggage. The road system, which must be one of the biggest and oldest systems going, carries far more than it’s share.

Some parts of the system have been totally re-engineered to a standard, well designed format - the canonical example is the motorways. Where this has happened the system can support far more traffic moving much faster in safety than the legacy system could. This implies that the whole system could be fine, but unfortunately, wholesale replacement is not an option due to the cost, so we have to basically make do and mend the ancient system. Whenever an old system is patched like that to extend it and keep it going, a plethora of discontinuities crops up. Whenever you try to mend one, it opens up new problems, both technical and political ones. The road system is a can of worms. If you open it, you have to eat some before you can get the top back on!

_________________
I stole this .sig

It drives me mad! there is no logic to any of the new limits, there must be a rule.

I wonder what makes one set of roadworks on a motorway 40 and another 50, i'm sure it has more to do with density of installable cameras than safety.

Drivers haven't got a hope of guessing correctly so we end up with camera victims driving at 40 causing chaos just incase they are in one of the new "safety" zones.

My other gripe is camera signs are almost built into the planning of any roadworks and many have no cameras at all, though i can see a logic for putting them up (create a panic breaking zone) etc. The fact there is no camera most time just increases my anger against the system, no other countries citizens would tolerate it!

We know the speed limits from the signs we pass, don't we? Why would we guess when we know what the limit is?

_________________
I stole this .sig

Fair point as long as there are plenty of signs, just that i don't understand why some are 40 and some are 50 when there doesn't appear to be any reason.

I would just like to know what makes the difference when they set the limit, i'm guessing there must be some degree of qualification for the limits not just what ever takes someones fancy.

Any ideas?

I don;t know, is the short answer. In situations where there does not appear to be any reason, would you like all roadworks to be 40, or all roadworks to be 50? Do you want a standard roadworks speed limit of some kind, or should it be varied according to the nature of things? What do you think should be done near roadworks?

_________________
I stole this .sig

I think the limit should be whatever is safe for the roadworkers, but consistant from county to county along the same roads, also i'd like a bit of technology ie when people are actually working set the limit to 40, 50, 60 eg whatevers safest.

But when people arn't working set the limit to whats safest then, ie 60, or 70 etc.


I'd have thought theres a relatively easy techy soloution to this or failing that a few big signs saying 40 limit between 9am-5pm Mon-Friday and 60 all other times, also the cameras could then be programmed to have a 40 limit in these hours and 60 limit out of these hours, a bit like setting a video recorder program?


Though it's probably a lot more complicated than i think..

The problem is that limits are reduced piecemeal where there is perceived to be a particular problem, leading to widespread inconsistencies.

For example, in a borough near me, there is a 40 limit on a built-up road which even I would admit is a fairly marginal candidate for a 40, but four miles away a mile of rural NSL A-road with no houses has been reduced to 30.

We need to return to consistent standards, with highway authorities only allowed to depart from them in genuinely exceptional cases.

_________________
"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

My gripe here is with limit signs being placed on a roundabout at the very start of the exit. With all the hassle involved in getting safely through a roundabout it is all too easy to miss signs in such a position. Personally I would then treat the limit as 30 mph until I got positive information to the contrary.

If you drive down the A592 at present, you encounter an open road with driveways, short straights between bends, and formerly all NSL, until recent tinkering with limits because of some bad accidents due to inappropriate speed, and overtaking.

Suddenly, there are two lollipop signs - the right hand saying NSL, the left hand saying 40mph, because some wag has rotated the sign on it's post.
Of course the highways people are on the ball, it's been like it for over a month that I know of!!

_________________
Time to take responsibility for our actions.. and don't be afraid of speaking out!