In message <st8d1e$13l$1@dont-email.me>, at 11:18:22 on Mon, 31 Jan
2022, Rolf Mantel <news@hartig-mantel.de> remarked:
>Am 31.01.2022 um 07:08 schrieb Roland Perry:
>> In message <d63evg18pcc2g49jmr9cba5gb89fpujnn3@4ax.com>, at 22:54:37 on
>> Sun, 30 Jan 2022, Charles Ellson <charlesellson@btinternet.com>
>> remarked:
>>> On Sat, 29 Jan 2022 10:53:11 +0000, Roland Perry <roland@perry.co.uk>
>>> wrote:
>>>
>>>> In message <st35cm$aj2$1@dont-email.me>, at 10:37:10 on Sat, 29 Jan
>>>> 2022, martin.coffee@round-midnight.org.uk remarked:
>>>>> On 29/01/2022 08:49, Tweed wrote:
>>>>>> Charles Ellson <charlesellson@btinternet.com> wrote:
>>>>>>> On Fri, 28 Jan 2022 18:12:40 -0000 (UTC), Tweed
>>>>>>> <usenet.tweed@gmail.com> wrote:
>>>>>>>
>>>>>>>> Charles Ellson <charlesellson@btinternet.com> wrote:
>>>>>>>>> On Fri, 28 Jan 2022 16:50:57 -0000 (UTC), Tweed
>>>>>>>>> <usenet.tweed@gmail.com> wrote:
>>>>>>>>>
>>>>>>>>>> <martin.coffee@round-midnight.org.uk> wrote:
>>>>>>>>>>> On 28/01/2022 16:13, mick wrote:
>>>>>>>>>>>> I am wondering drivers brains don't register the lower orange
>>>>>>>>>>>> and black
>>>>>>>>>>>> stripes.  Perhaps a colour change to the flourecent yellow
>>>>>>>>>>>>
>>>>>>>>>>>> would make it stand out better.
>>>>>>>>>>>>
>>>>>>>>>>>> https://www.bbc.co.uk/news/uk-england-cambridgeshire-60170620
>>>>>>>>>>>>
>>>>>>>>>>> Personally I think nothing short of a permanent driving ban
>>>>>>>>>>>
>>>>>>>>>>> inroads in these drivers.
>>>>>>>>>>
>>>>>>>>>> Nothing like depriving the working classes of their
>>>>>>>>>>livelihoods to keep
>>>>>>>>>> them in their place eh?
>>>>>>>>>>
>>>>>>>>> Nothing like playing the Anglo-Norman class game to evade
>>>>>>>>> responsibility for criminality ?
>>>>>>>>
>>>>>>>> In my book genuine criminality involves some sort of malicious intent,
>>>>>>>> though I admit the law often sees otherwise. I doubt the average bridge
>>>>>>>> basher sets off with the intent of hitting a bridge.
>>>>>>>>
>>>>>>> Gross negligence can be an element in various criminal offences (e.g.
>>>>>>> manslaughter, dangerous driving) with or without intent.
>>>>>>>
>>>>>> Yes, legally that’s true. But in my personal classification of moral
>>>>>> behaviour there’s a difference between intending to do something bad
>>>>>> (criminal) and being totally stupid (gross negligence). If you intend to
>>>>>> neglect to do something, such as not bothering to maintain dangerous
>>>>>> equipment or not bothering to fit a machine guard when you know
>>>>>>you should,
>>>>>> well that’s intended and criminal. Likewise, dangerous driving is
>>>>>> intentional, whereas careless driving probably isn’t, but both are
>>>>>> classified as criminal offences.
>>>>>>
>>>>> I would suggest that failure to compare the bridge height sign with
>>>>> that written in the vehicle is negligence.
>>>>
>>>> It might be slightly more than that, because all the bridges in the
>>>> top-ten have I think red-circle prohibition signs, not red-triangle
>>>> advisory signs.

>> <deep sigh> Upwards pointing triangular height warning signs.
>> Sometimes they get changed, the ones at Queen Adelaide are now
>>circles.

>> http://perry.co.uk/images/QA-nearmiss-Sept-2018.jpg That HGV
>>stopped before it hit the bridge, but still blocked the road for
>>quite some time while it tried to do an n-point turn.
>>
>>> Which doesn't include point-downwards versions such as Give Way
>>>signs
>>> (now the sole example?) and IIRC a few older short-lived Stop signs.

>> And that site really needs a give-way sign which applies to the
>>bridge hole (not the junction 100yds beyond) as it's barely wide
>>enough for two small cars to pass, let alone a-tractor-plus-anything
>>(etc).
>
>Are you now confusing 'give way' at a junction with 'oncoming traffic
>has priority' (sign 615)?

No. But that sign might work almost as well, although the bridge is on a
bend and you can't really see if there's oncoming traffic until it's
almost too late.

On a wider note, it was predicted, and I'm sure has come true, that the
new Ely bypass has triggered much increased rat-running along the
eastern bank of the river (and round the new bypass, and onwards to the
south).

I was in a queue of about a dozen cars at the staggered junction at QA
this morning (where priority is for the relatively very lightly
trafficed Prickwillow Rd) and I was the only one who then went towards
North Ely (and the two level crossings) rather than heading for Stuntney
Rd. That's very typical.
--
Roland Perry

On 29/01/2022 15:40, Tweed wrote:
> Roland Perry <roland@perry.co.uk> wrote:

>> Good luck editing out this: <http://www.perry.co.uk/images/signage-
>> March-2020.jpg>
>>
> Actually I fear it’s exactly the sort of sign I’d edit out. Perhaps
> alternating flashing yellows on the sign might draw my attention to it. The
> other issue is how complex the road is immediately before the bridge. If
> your brain’s processing power is diverted to avoiding a crash, giving way,
> turning at a complex junction etc it’s very easy to miss a sign.

There are 11 signs (possibly 12) in that picture.

Isn't that rather a lot to process for someone who also has to drive a
vehicle? Particularly, a van they have hired that they are unfamiliar
with.

Some of the signs are facing the other way, but the driver's brain needs
to recognise that, although they are sign shaped, they can be ignored.

The sensible thing to do would be to remove as much as possible of the
extraneous signage.

There is no need for two level crossing signs. And maybe they could be
moved, anyway?

Is one of those signs some sort of Welcome to the County signs? Another,
about parking?

There ought to be some research to find out whether two low bridge
signs, on both sides of the road, are actually more effective than one.

Maybe cut down on the verbiage? "300 yds ahead" is useful, but not
essential. Maybe, it detracts from the essential message?

In article <st8mis$7ho$1@dont-email.me>, NOTsomeone@microsoft.invalid
says...
>
> The sensible thing to do would be to remove as much as possible of the
> extraneous signage.

This!

There are simply too many signs on the roads, most of which appear to be
there because someone is covering their arse, rather than because they
add to safety.

And then there are the "new road layout ahead" ones which have been
there for 5 years or more.

I propose a rule: there should be no more than one sign every 5 seconds
of driving time at the speed limit in force. If you genuinely can't
remove enough superfluous signs to meet that limit, then the speed limit
has to be reduced.

John

In message <MPG.3c61f16aca6a23da9897b0@news.eternal-september.org>, at
13:15:57 on Mon, 31 Jan 2022, John Aldridge <jpsa@cantab.net> remarked:

>And then there are the "new road layout ahead" ones which have been
>there for 5 years or more.

My favourite is "Changed priorities ahead", which makes me think about
the Liberal Party when they joined the coalition. Which shows how long
some like that have been in place (and still are).
--
Roland Perry

On 31/01/2022 13:15, John Aldridge wrote:
> And then there are the "new road layout ahead" ones which have been
> there for 5 years or more.

Aren't they only supposed to be displayed for a limited period, I think
it is in "Traffic signs manual" somewhere.

In message <st8mis$7ho$1@dont-email.me>, at 13:01:16 on Mon, 31 Jan
2022, GB <NOTsomeone@microsoft.invalid> remarked:
>On 29/01/2022 15:40, Tweed wrote:
>> Roland Perry <roland@perry.co.uk> wrote:
>
>>> Good luck editing out this: <http://www.perry.co.uk/images/signage-
>>> March-2020.jpg>
>>>
>> Actually I fear it’s exactly the sort of sign I’d edit out. Perhaps
>> alternating flashing yellows on the sign might draw my attention to it. The
>> other issue is how complex the road is immediately before the bridge. If
>> your brain’s processing power is diverted to avoiding a crash, giving way,
>> turning at a complex junction etc it’s very easy to miss a sign.
>
>There are 11 signs (possibly 12) in that picture.
>
>Isn't that rather a lot to process for someone who also has to drive a
>vehicle? Particularly, a van they have hired that they are unfamiliar
>with.

In that case they need to reconsider whether they are competent to drive
a hired van.

The "Level Crossing Ahead Closed" was added about a year after the big
blue signs, perhaps because (as is reported for the latest bash) the
driver's excuse was "I was following my satnav".

>Some of the signs are facing the other way, but the driver's brain
>needs to recognise that, although they are sign shaped, they can be
>ignored.

They greyness makes them very easy to tune out.

>The sensible thing to do would be to remove as much as possible of the
>extraneous signage.
>
>There is no need for two level crossing signs. And maybe they could be
>moved, anyway?

The idea is probably that maybe some people would stop, and take the
road to the right as a detour (not the optimal detour, but better than
losing the roof).

There are more signs closer to the bridge, and on the bridge.

>Is one of those signs some sort of Welcome to the County signs?
>Another, about parking?

One is "Welcome to the City", combined with a "Free Parking", which is
somewhat of a local sore point (the traders and residents want to keep
it that way, the council keeps threatening to impose charging, to pay
for traffic wardens to combat unlawful street-parking). The sign has
been there a decade or more.

The yellow sign has been removed for at last a year now, and I think was
a temporary "Level crossing now closed" sign. It wasn't there in:

http://www.perry.co.uk/images/signage-March-2019.jpg

None of these minor signage tweaks has appeared to have any effect on
the number of bashes (either up or down).

>There ought to be some research to find out whether two low bridge
>signs, on both sides of the road, are actually more effective than one.

It's normally accepted that signs both sides of the road create a
"gateway" to the road they are informing the driver about, in case
there's some ambiguity that they might apply to a sideroad.

>Maybe cut down on the verbiage? "300 yds ahead" is useful, but not
>essential. Maybe, it detracts from the essential message?

In another context I happened to have a conversation with someone who
was a retired traffic-signage engineer. And his contribution was that
the position of wording on the sign wasn't important (so not reading
expecting people to read from the top down for example) but rather
biggest-size first.

To that extent the signs which are literally as big as the back of a bus
should be expected to take priority.

And on those signs the roundel is the biggest object.

You can't delete the "Low Bridge ahead", because there are places in
those 300yds [a boatyard, a playing field] where vehicles higher than
2.7m are allowed. So this is a warning of an impending height
restriction, not the *start* of the height restriction.
--
Roland Perry

In message <st8ou5$ne9$1@dont-email.me>, at 13:41:25 on Mon, 31 Jan
2022, MB <MB@nospam.net> remarked:

>On 31/01/2022 13:15, John Aldridge wrote:

>> And then there are the "new road layout ahead" ones which have been
>> there for 5 years or more.
>
>Aren't they only supposed to be displayed for a limited period, I think
>it is in "Traffic signs manual" somewhere.

I've talked with councillors several times about this, and the problem
is that there's no budget for them to be removed, or even a budget for a
5-10yr diary to alert a person who isn't there (because he's not in the
budget either), that *had* there been a budget for a man with a
screwdriver, they should be sent out to do the deed.

[Sorry if that's a bit recursive]
--
Roland Perry

On 29/01/2022 18:29, Roland Perry wrote:
> In message <st3pe3$uio$1@dont-email.me>, at 16:19:15 on Sat, 29 Jan
> 2022, MB <MB@nospam.net> remarked:
>
>> On 29/01/2022 15:16, Roland Perry wrote:
>>> There have been numerous academic studies (I decided to go looking for
>>> them a couple of years ago).
>>
>> What if they built the bridges so solid that even a bridge strike by a
>> large vehicle would not damage it.  It would cost more but there would
>> not be the regular costs or inspections and repairs.
>
> There are thousands of bridges, it would cost a fortune. Just as
> erecting beams in front of thousands of bridges would cost a smaller
> fortune. The problem with the latter is they typically require repairing
> if something crashes into them, which is why they aren't recommended
> (even where legal).
>
> So what they do is install custom measures at a handful of bridges. And
> live with the consequences. We are where we are.
>
> The most helpful measure at the Ely underpass would be to lower the road
> an inch, at which point the number of bashes would reduce to about a
> tenth. Of the dozen a year I've tracked the last six years, only one in
> ten was a vehicle that was more than half an inch too tall.

Wouldn't it be cheaper just to change all the signage to say that the
height is 2.6m (instead of the present 2.7m)?

Perhaps, what is really happening is that drivers are well aware of the
height of their van. They know they are close to the indicated bridge
height, but they reckon there's probably a safety margin built in. So,
build in a bigger safety margin, and it will all be fine!

On 31/01/2022 14:11, GB wrote:
> Wouldn't it be cheaper just to change all the signage to say that the
> height is 2.6m (instead of the present 2.7m)?

Wouldn't drivers get used to that and believe there was always an extra
few inches clearance?

On 31/01/2022 14:22, MB wrote:
> On 31/01/2022 14:11, GB wrote:
>> Wouldn't it be cheaper just to change all the signage to say that the
>> height is 2.6m (instead of the present 2.7m)?
>
> Wouldn't drivers get used to that and believe there was always an extra
> few inches clearance?
>

You may well be right.

Roland's solution is to make the actual height 3cms bigger, by lowering
the road. Possibly, drivers will keep misjudging the new height. So,
perhaps there'll still be a spate of collisions involving only an inch
or two of overheight?

In fact, until research is done into what causes the problem, it's not
sensible to try any expensive solutions. Cheap changes, that seem
plausible, are in effect part of the research process.

In message <MPG.3c61f16aca6a23da9897b0@news.eternal-september.org>, at
13:15:57 on Mon, 31 Jan 2022, John Aldridge <jpsa@cantab.net> remarked:

>I propose a rule: there should be no more than one sign every 5 seconds
>of driving time at the speed limit in force. If you genuinely can't
>remove enough superfluous signs to meet that limit, then the speed limit
>has to be reduced.

In an area like the town-side of Ely Station, that would mean a speed
limit of about 5mph, because there's so much going on.

A roundabout, a pelican crossing [do traffic lights and Keep Left
bollards count as one or three, and don't get me started about green/red
men pointing along the road rather than across it
<https://goo.gl/maps/wzXtwB1yAnmJ6kgg6> ] and a station entrance, quite
apart from the underpass and the closed level crossing.

Also, these bridge bashes haven't accelerated with increased signage,
they have merely not reduced.

It's human nature to look at a bridge being bashed, when all there is to
prevent it is one dinner-plate sized roundel, and think "maybe if we
made the signs bigger / or put some Tiger Stripes on / or installed more
signs on the roads leading to the bridge" that it would deter the
drivers.

What's actually required is more research into why drivers ignore the
signs, however big or many there are. My own hunch is that they *do* see
the signs, but for some reason don't think they apply to the vehicle
they are driving.
--
Roland Perry

In message <st8qmu$ur$1@dont-email.me>, at 14:11:43 on Mon, 31 Jan 2022,
GB <NOTsomeone@microsoft.invalid> remarked:
>On 29/01/2022 18:29, Roland Perry wrote:
>> In message <st3pe3$uio$1@dont-email.me>, at 16:19:15 on Sat, 29 Jan
>>2022, MB <MB@nospam.net> remarked:
>>
>>> On 29/01/2022 15:16, Roland Perry wrote:
>>>> There have been numerous academic studies (I decided to go looking for
>>>> them a couple of years ago).
>>>
>>> What if they built the bridges so solid that even a bridge strike by
>>>a large vehicle would not damage it.  It would cost more but there
>>>would not be the regular costs or inspections and repairs.
>> There are thousands of bridges, it would cost a fortune. Just as
>>erecting beams in front of thousands of bridges would cost a smaller
>>fortune. The problem with the latter is they typically require
>>repairing if something crashes into them, which is why they aren't
>>recommended (even where legal).
>> So what they do is install custom measures at a handful of bridges.
>>And live with the consequences. We are where we are.
>> The most helpful measure at the Ely underpass would be to lower the
>>road an inch, at which point the number of bashes would reduce to
>>about a tenth. Of the dozen a year I've tracked the last six years,
>>only one in ten was a vehicle that was more than half an inch too tall.
>
>Wouldn't it be cheaper just to change all the signage to say that the
>height is 2.6m (instead of the present 2.7m)?

It's probably not allowed, and the clearance is 2.85m anyway - I've
measured it.

>Perhaps, what is really happening is that drivers are well aware of the
>height of their van.

I'm convinced that's not the case. Apart from one local plumber, I think
it was, who bashed his brand new van into it and said "well, my old van
fitted OK".

>They know they are close to the indicated bridge height, but they
>reckon there's probably a safety margin built in. So, build in a bigger
>safety margin, and it will all be fine!

Is 15cm not sufficient?
--
Roland Perry

In message <st8s8f$480$1@dont-email.me>, at 14:38:08 on Mon, 31 Jan
2022, GB <NOTsomeone@microsoft.invalid> remarked:
>On 31/01/2022 14:22, MB wrote:
>> On 31/01/2022 14:11, GB wrote:
>>> Wouldn't it be cheaper just to change all the signage to say that the
>>> height is 2.6m (instead of the present 2.7m)?
>> Wouldn't drivers get used to that and believe there was always an
>>extra few inches clearance?
>>
>
>You may well be right.
>
>Roland's solution is to make the actual height 3cms bigger, by lowering
>the road.

Which my well be not enough to trigger the signage going to the next
step up (2.8m I presume). But remember that would actually be the
current 2.85m + 0.03

The reason for lowering the road isn't to play salami-slicing with the
signage, but because there's a substantial feet of vehicles out there
which appear to be 2.86-2.87m tall

>Possibly, drivers will keep misjudging the new height.

The aren't misjudging it (do you really think they can estimate the
height of such a bridge, at a closing speed of typically 15mph, to the
nearest cm).

No, they have some reason for thinking their vehicle will fit, and it's
not doing mental arithmetic comparing the signage to the number that
isn't on a sticker in the cab, and isn't in the vehicle's glovebox
manual either (because the manual, which is almost certainly missing,
will be for the generic chassis and cab, not the chassis-cab plus an
aftermarket box on the back).

>So, perhaps there'll still be a spate of collisions involving only an
>inch or two of overheight?

Not if there's in practice a negligible fleet of vans whose inherent
height is 2.88-3m high.

>In fact, until research is done into what causes the problem, it's not
>sensible to try any expensive solutions. Cheap changes, that seem
>plausible, are in effect part of the research process.

I'm not sure anyone is doing that research (other than my attempts in
places such as this).

It's pretty clear Network Rail in Ely are just ordering more popcorn and
chuckling about the balsa-wood vans [literally] topping themselves on
the two foot thick raft of reinforced concrete with movement sensors.
--
Roland Perry

On 31/01/2022 15:03, Roland Perry wrote:

>> They know they are close to the indicated bridge height, but they
>> reckon there's probably a safety margin built in. So, build in a
>> bigger safety margin, and it will all be fine!
>
> Is 15cm not sufficient?

You want to spend say £1m lowering the roadway in order to make the
margin 18cm. :)

You have no evidence that it will work. Yes, I know that 9 out of 10
collisions were caused by drivers only misjudging by a couple of cms,
but you have no evidence that they won't continue to do so after the
road is expensively lowered.

GB <NOTsomeone@microsoft.invalid> wrote:
> On 31/01/2022 15:03, Roland Perry wrote:
>
>>> They know they are close to the indicated bridge height, but they
>>> reckon there's probably a safety margin built in. So, build in a
>>> bigger safety margin, and it will all be fine!
>>
>> Is 15cm not sufficient?
>
> You want to spend say £1m lowering the roadway in order to make the
> margin 18cm. :)
>
> You have no evidence that it will work. Yes, I know that 9 out of 10
> collisions were caused by drivers only misjudging by a couple of cms,
> but you have no evidence that they won't continue to do so after the
> road is expensively lowered.

I’ve tried to take this up with Roland before but he insists, without much
in the way of evidence except that the vans that are a couple of inches too
tall are the ones that hit the bridge, that there is a break point in the
distribution of van heights at around 2.85.

Sam

--
The entity formerly known as Sam.Wilson@ed.ac.uk
Spit the dummy to reply

On 31/01/2022 15:15, Roland Perry wrote:
> In message <st8s8f$480$1@dont-email.me>, at 14:38:08 on Mon, 31 Jan
> 2022, GB <NOTsomeone@microsoft.invalid> remarked:
>> On 31/01/2022 14:22, MB wrote:
>>> On 31/01/2022 14:11, GB wrote:
>>>> Wouldn't it be cheaper just to change all the signage to say that the
>>>> height is 2.6m (instead of the present 2.7m)?
>>>  Wouldn't drivers get used to that and believe there was always an
>>> extra  few inches clearance?
>>>
>>
>> You may well be right.
>>
>> Roland's solution is to make the actual height 3cms bigger, by
>> lowering the road.
>
> Which my well be not enough to trigger the signage going to the next
> step up (2.8m I presume). But remember that would actually be the
> current 2.85m + 0.03
>
> The reason for lowering the road isn't to play salami-slicing with the
> signage, but because there's a substantial feet of vehicles out there
> which appear to be 2.86-2.87m tall

Perhaps there really are loads of vehicles 2.86-2.87m tall. But, it
seems rather unlikely, especially with "a negligible fleet of vans whose
inherent height is 2.88-3m high".

You could be right in that surmise, but, before persuading anybody to
spend loads of money lowering the roadway, you ought to justify it. I'm
not sure how? Is there a database of vehicle heights?

> No, they have some reason for thinking their vehicle will fit

Or, they are just distracted, not thinking about it?

>> In fact, until research is done into what causes the problem, it's not
>> sensible to try any expensive solutions. Cheap changes, that seem
>> plausible, are in effect part of the research process.
>
> I'm not sure anyone is doing that research (other than my attempts in
> places such as this).
>
> It's pretty clear Network Rail in Ely are just ordering more popcorn and
> chuckling about the balsa-wood vans [literally] topping themselves on
> the two foot thick raft of reinforced concrete with movement sensors.

It is chuckle time, really. Unlike the double decker buses trying to fit
under single decker bridges, nobody is hurt when a van gets topped.

Who would be interested enough to pay for research to be done?

Roland Perry <roland@perry.co.uk> wrote:
> In message <MPG.3c61f16aca6a23da9897b0@news.eternal-september.org>, at
> 13:15:57 on Mon, 31 Jan 2022, John Aldridge <jpsa@cantab.net> remarked:
>
>> I propose a rule: there should be no more than one sign every 5 seconds
>> of driving time at the speed limit in force. If you genuinely can't
>> remove enough superfluous signs to meet that limit, then the speed limit
>> has to be reduced.
>
> In an area like the town-side of Ely Station, that would mean a speed
> limit of about 5mph, because there's so much going on.
>
> A roundabout, a pelican crossing [do traffic lights and Keep Left
> bollards count as one or three, and don't get me started about green/red
> men pointing along the road rather than across it
> <https://goo.gl/maps/wzXtwB1yAnmJ6kgg6> ] and a station entrance, quite
> apart from the underpass and the closed level crossing.
>
> Also, these bridge bashes haven't accelerated with increased signage,
> they have merely not reduced.
>
> It's human nature to look at a bridge being bashed, when all there is to
> prevent it is one dinner-plate sized roundel, and think "maybe if we
> made the signs bigger / or put some Tiger Stripes on / or installed more
> signs on the roads leading to the bridge" that it would deter the
> drivers.
>
> What's actually required is more research into why drivers ignore the
> signs, however big or many there are. My own hunch is that they *do* see
> the signs, but for some reason don't think they apply to the vehicle
> they are driving.

For the van hire drivers I wonder if they are otherwise car drivers? If so,
they may never pay attention to height signs as there’s no need when
driving a car. I know that I as a car driver never process height signs.

In article <EEIWyFZch$9hFA2Q@perry.uk>, roland@perry.co.uk says...
>
> In message <MPG.3c61f16aca6a23da9897b0@news.eternal-september.org>, at
> 13:15:57 on Mon, 31 Jan 2022, John Aldridge <jpsa@cantab.net> remarked:
>
> >I propose a rule: there should be no more than one sign every 5 seconds
> >of driving time at the speed limit in force. If you genuinely can't
> >remove enough superfluous signs to meet that limit, then the speed limit
> >has to be reduced.
>
> In an area like the town-side of Ely Station, that would mean a speed
> limit of about 5mph, because there's so much going on.

So be it, then. I don't think it's reasonable to expect people to read,
understand, and deduce the consequences for them, of a sign much more
often than that.

--
John

In message <st91iu$seq$1@dont-email.me>, at 16:09:02 on Mon, 31 Jan
2022, Tweed <usenet.tweed@gmail.com> remarked:
>Roland Perry <roland@perry.co.uk> wrote:
>> In message <MPG.3c61f16aca6a23da9897b0@news.eternal-september.org>, at
>> 13:15:57 on Mon, 31 Jan 2022, John Aldridge <jpsa@cantab.net> remarked:
>>
>>> I propose a rule: there should be no more than one sign every 5 seconds
>>> of driving time at the speed limit in force. If you genuinely can't
>>> remove enough superfluous signs to meet that limit, then the speed limit
>>> has to be reduced.
>>
>> In an area like the town-side of Ely Station, that would mean a speed
>> limit of about 5mph, because there's so much going on.
>>
>> A roundabout, a pelican crossing [do traffic lights and Keep Left
>> bollards count as one or three, and don't get me started about green/red
>> men pointing along the road rather than across it
>> <https://goo.gl/maps/wzXtwB1yAnmJ6kgg6> ] and a station entrance, quite
>> apart from the underpass and the closed level crossing.
>>
>> Also, these bridge bashes haven't accelerated with increased signage,
>> they have merely not reduced.
>>
>> It's human nature to look at a bridge being bashed, when all there is to
>> prevent it is one dinner-plate sized roundel, and think "maybe if we
>> made the signs bigger / or put some Tiger Stripes on / or installed more
>> signs on the roads leading to the bridge" that it would deter the
>> drivers.
>>
>> What's actually required is more research into why drivers ignore the
>> signs, however big or many there are. My own hunch is that they *do* see
>> the signs, but for some reason don't think they apply to the vehicle
>> they are driving.
>
>For the van hire drivers I wonder if they are otherwise car drivers? If so,
>they may never pay attention to height signs as there’s no need when
>driving a car. I know that I as a car driver never process height signs.

I look at height signs (although haven't yet encountered a bridge that
was too low, just one multi-storey car park which had lots of plumbing
attached to the ceiling). With roof-bars on, 1.85m

In other news, someone commenting on the recent Ely bash has suggested
that it was because the van was empty, and the driver knew it would fit
if loaded. Err, no, I don't think the suspension is that soggy.

One of the changes made while it was closed for a year as part of the
Bypass/Crossing-closure project, was to widen the pavement and make it
single-alternate with traffic lights. And another punter suggests that
people are distracted by them and race through while still on green. The
problem with that analysis is that before the lights were installed, it
was bashed just as often.

And in practice getting a through-run is almost unheard of, and stopping
in a small queue for the lights is almost a certainty. Especially a the
time of day of the last bash. Therefore most drivers have ten or twenty
seconds to contemplate the bridge, tiger stripes and height prohibition
signage, while they wait.
--
Roland Perry

In message <MPG.3c622b5393eaab99897b1@news.eternal-september.org>, at
17:23:07 on Mon, 31 Jan 2022, John Aldridge <jpsa@cantab.net> remarked:
>In article <EEIWyFZch$9hFA2Q@perry.uk>, roland@perry.co.uk says...
>>
>> In message <MPG.3c61f16aca6a23da9897b0@news.eternal-september.org>, at
>> 13:15:57 on Mon, 31 Jan 2022, John Aldridge <jpsa@cantab.net> remarked:
>>
>> >I propose a rule: there should be no more than one sign every 5 seconds
>> >of driving time at the speed limit in force. If you genuinely can't
>> >remove enough superfluous signs to meet that limit, then the speed limit
>> >has to be reduced.
>>
>> In an area like the town-side of Ely Station, that would mean a speed
>> limit of about 5mph, because there's so much going on.
>
>So be it, then. I don't think it's reasonable to expect people to read,
>understand, and deduce the consequences for them, of a sign much more
>often than that.

And what about the three or four previous signs they've seen, further
away on the approach roads, where they are the only one?

This montage also gives an idea of the size (big as the back of an HGV).

http://www.perry.co.uk/images/A142-signage.jpg

A good five seconds to the next and also to the one after that:

https://goo.gl/maps/GGV8FEW2TYsrUbJs8

Would you recommend a 15mph speed limit here, so drivers can take in and
comprehend the five signs (recursively, two of which are "30") and the
two backs of signs?

https://goo.gl/maps/yQTgxYD5X7CUfCPq7

And do these two illegal signs change the equation at all?

https://goo.gl/maps/dPBxwJNPRU17BW6Z7

[It's a separate debate, but I would support giving the local authority
powers to remove such illegal signs in the same way they'd clear up
litter. But currently it doesn't work like that.]

In other news, how many signs here, and what speed limit would you
impose. If the 30mph speed limit indicated only two were allowed, which
of the others would you remove? https://goo.gl/maps/g4KpG74rM3TFf6ym8
--
Roland Perry

In message <st90op$9if$1@dont-email.me>, at 15:55:06 on Mon, 31 Jan
2022, GB <NOTsomeone@microsoft.invalid> remarked:
>On 31/01/2022 15:15, Roland Perry wrote:
>> In message <st8s8f$480$1@dont-email.me>, at 14:38:08 on Mon, 31 Jan
>>2022, GB <NOTsomeone@microsoft.invalid> remarked:
>>> On 31/01/2022 14:22, MB wrote:
>>>> On 31/01/2022 14:11, GB wrote:
>>>>> Wouldn't it be cheaper just to change all the signage to say that the
>>>>> height is 2.6m (instead of the present 2.7m)?
>>>>  Wouldn't drivers get used to that and believe there was always an
>>>>extra  few inches clearance?
>>>>
>>>
>>> You may well be right.
>>>
>>> Roland's solution is to make the actual height 3cms bigger, by
>>>lowering the road.

>> Which my well be not enough to trigger the signage going to the next
>>step up (2.8m I presume). But remember that would actually be the
>>current 2.85m + 0.03

>> The reason for lowering the road isn't to play salami-slicing with
>>the signage, but because there's a substantial feet of vehicles out
>>there which appear to be 2.86-2.87m tall
>
>Perhaps there really are loads of vehicles 2.86-2.87m tall. But, it
>seems rather unlikely, especially with "a negligible fleet of vans
>whose inherent height is 2.88-3m high".

Yes, there really really are loads of vehicles that just-don't-quite-
fit. That particular model of Mercedes with the wind deflector over the
cab (and a couple of other makes which are essentially clones).

As for an absence of vehicles in the 2.88m-3m range that's again
something which can be observed. I don't know if there's a regulatory
reason, but if we think about engine sizes, there are huge numbers of
cars with 1098cc engines and very few 1101-1190 (the next increment
typically being 1198).

>You could be right in that surmise, but, before persuading anybody to
>spend loads of money lowering the roadway, you ought to justify it. I'm
>not sure how?

Mainly by showing pictures (I'm getting quite fed up posting them,
apparently to no effect) of identical-looking vehicles being the most
common casualty at the bridge.

For a final time:

http://www.perry.co.uk/images/DPD_18-09-2017.jpg

[Yes, I know, Delivering Parcels Dangerously].

>Is there a database of vehicle heights?

Part of the problem is that the data is dispersed amongst lots of
manufacturer databases. And then there's the custom-backs which people
like Tesco and hire companies fix on the back of a chassis, where the
database can only realistically have the height of the cab section,
before the back-end was added.

Maybe the DVLA database (linked to the licence plate) should also have
the individual height of the custom-built vehicle in it (as well as the
other stuff about engine sizes and CO2 G/KM). Although I wonder if the
latter can be properly measured and recorded once a custom-back and its
custom air resistance has been added to a chassis/cab delivered from the
factory.

In case people are unfamiliar with the concept:

<https://www.van-discount.co.uk/wp-content/uploads/2020/09/2014-ford-
transit-chassis-cab.jpg>

>> No, they have some reason for thinking their vehicle will fit
>
>Or, they are just distracted, not thinking about it?

They would need to be multiply-distracted, because by the time they get
to that bridge they'll have passed about six signs dotted along three
quarters of a mile (that's counting signs on both sides of the road as
'one')

>>> In fact, until research is done into what causes the problem, it's
>>>not sensible to try any expensive solutions. Cheap changes, that
>>>seem plausible, are in effect part of the research process.

>> I'm not sure anyone is doing that research (other than my attempts
>>in places such as this).

>> It's pretty clear Network Rail in Ely are just ordering more popcorn
>>and chuckling about the balsa-wood vans [literally] topping
>>themselves on the two foot thick raft of reinforced concrete with
>>movement sensors.
>
>It is chuckle time, really. Unlike the double decker buses trying to
>fit under single decker bridges, nobody is hurt when a van gets topped.

Not directly hurt, but the subsequent traffic jams and delays may have
collateral damage, such as patients late arriving at hospital.

>Who would be interested enough to pay for research to be done?

Shroud-waving Network Rail would be the prime candidate.

The first step might be to conduct "exit interviews" with the perps. To
determine their views on why they ignored all the warnings. There's a
bit of that with the latest one, where there's a hint in the reporting
the driver said "I was following my Satnav", but he probably doesn't
have a satnav that's cognoscent of the height of the vehicle he's
driving. And/or an out of date map. So whose fault is that?
--
Roland Perry

In message <st8v6q$59j$1@dont-email.me>, at 15:28:27 on Mon, 31 Jan
2022, GB <NOTsomeone@microsoft.invalid> remarked:
>On 31/01/2022 15:03, Roland Perry wrote:
>
>>> They know they are close to the indicated bridge height, but they
>>>reckon there's probably a safety margin built in. So, build in a
>>>bigger safety margin, and it will all be fine!

>> Is 15cm not sufficient?
>
>You want to spend say £1m lowering the roadway in order to make the
>margin 18cm. :)

You have no evidence it would cost that much.

>You have no evidence that it will work.

I think I have plenty.

>Yes, I know that 9 out of 10 collisions were caused by drivers only
>misjudging by a couple of cms,

They should not be judging the height on-the-fLy as they approach, when
their vehicle is *at least* 15cm taller than the number on the signage.

>but you have no evidence that they won't continue to do so

The evidence for that is the lack of any candidate vehicles whose height
is in that inch-higher-then-the-current-victims bracket.

>after the road is expensively lowered.

Network Rail need to tone down the shroud-waving and decide if a simple
remedy in this instance is cost-effective.

--
Roland Perry

In message <st907b$ssj$1@dont-email.me>, at 15:45:47 on Mon, 31 Jan
2022, Sam Wilson <ukr@dummy.wislons.fastmail.co.uk> remarked:
>GB <NOTsomeone@microsoft.invalid> wrote:
>> On 31/01/2022 15:03, Roland Perry wrote:
>>
>>>> They know they are close to the indicated bridge height, but they
>>>> reckon there's probably a safety margin built in. So, build in a
>>>> bigger safety margin, and it will all be fine!
>>>
>>> Is 15cm not sufficient?
>>
>> You want to spend say £1m lowering the roadway in order to make the
>> margin 18cm. :)
>>
>> You have no evidence that it will work. Yes, I know that 9 out of 10
>> collisions were caused by drivers only misjudging by a couple of cms,
>> but you have no evidence that they won't continue to do so after the
>> road is expensively lowered.
>
>I’ve tried to take this up with Roland before but he insists, without much
>in the way of evidence except that the vans that are a couple of inches too
>tall are the ones that hit the bridge, that there is a break point in the
>distribution of van heights at around 2.85.

Find me some which are. It might take you a while.

An analogy I've used before is multi-storeys and SUVs. Typically the
former will have a height limit of 2m, and that works fine because even
the taller SUVs are rarely above 1.85m. If there were significant
numbers of SUVs that are 2.05m tall, I'm sure we'd have heard the
complaints about them being excluded from the facilities everyone
else uses.
--
Roland Perry

On 01/02/2022 01:51, Nobody wrote:
> Blimey! I hope Brits don't have to deal with signs instructing the
> direction of wiping a....?

That is the least of your problems, the Greenies will probably bring in
a law that you must use both sides of the paper.

On 01/02/2022 08:19, Roland Perry wrote:
> An analogy I've used before is multi-storeys and SUVs. Typically the
> former will have a height limit of 2m, and that works fine because even
> the taller SUVs are rarely above 1.85m. If there were significant
> numbers of SUVs that are 2.05m tall, I'm sure we'd have heard the
> complaints about them being excluded from the facilities everyone
> else uses.

Whenever I used to use the roof box on my car, I always measured the
total height and stuck a note on the dashboard. More for barriers on car
parks than multi-story car parks.