Should Speed Limits Be Banned?

[Jolliffee]

I enjoyed this article so thought it needed to be shared?

Should Speed Limits be Banned?

by Robert Clarke.

"They say if you want to keep your friends, don’t talk about religion or politics. Well perhaps speeding should also be added to that list, as while everybody seems to have an opinion on the matter, it has in modern times become one of the most strongly disputed issues within our society.

In recent years British motorists have witnessed a dramatic increase in the number of speed enforcement measures installed on our roads. Whether it’s GATSO, Truvelo, SPECS, unmarked police patrol vehicles or handheld laser devices, it seems there’s now no escaping the eye of the law, for Big Brother is watching you. If you’re travelling at 78mph down the M4 you had best watch out, for you are now a criminal…or so we have been indoctrinated to believe. We are told that speeding is the direct cause of almost all fatal or major road accidents, but what exactly do we mean by “speeding”? In the eyes of the law (and the speed camera), speeding is defined as driving a motor vehicle in excess of the limit for any given public road, whether it be by 1mph or 100mph- it is illegal... but is it necessarily dangerous?

When conditions allow...

When assessing the maximum speed at which it is safe to travel there are simply too many contributing variable factors on our roads to construe that if you are travelling greater than the posted limit it is inevitably dangerous. It is impossible to deduce any kind of accurate judgment until evaluating-

- The conditions on the road (dry, wet, icy etc)

- The driver’s ability (fatigue, age, emotion, mind concentration, drug influence etc)

- The vehicle's mechanical condition (drive-train, tyres, brakes, steering etc.)

- The volume of traffic on the road (congested, moderate, quiet)

- Visibility conditions (foggy, day, night, storm etc)

Without taking all of these contributing factors into consideration it is unfeasible to formulate any accurate conception of what a dangerous speed is for any given road. Interestingly, the simple fact of the matter is that no speed camera is capable of evaluating any of these factors - and that’s precisely where opinions differ. The law defines speeding as “too fast for the limit”, when the simple reality is that it really means “too fast for the conditions”. Road fatalities related to speeding only ever occur when a driver fails to accurately evaluate one or more of the five factors listed above, not solely because a posted limit is exceeded.

While a staggeringly large majority of speeding tickets are issued for drivers travelling too fast for the limit as opposed to too fast for the actual conditions, it seems a fair assessment to say that speed doesn’t kill at all - it pays. A bold statement to make you might be thinking, but when you consider that the UK Department for Transport statistics show that road deaths have increased where speed cameras are most prevalent, it begins to make sense.

Do speed cameras kill?

Take for example, Cumbria. When the number of speed camera sites grew by a whopping 48%, you would have expected to see a dramatic fall in the number of road fatalities in that area, when in fact they grew by a morbid 17%. Before 2003, when Cumbria’s speed camera partnership was first inaugurated, the area saw 49 road fatalities in two consecutive years. Once 33 speed camera sites were active, this figure jumped to 54. In 2004, when the number of speed camera sites grew to 49, fatalities figures once again rose, this time to 57.

While in 2004, road deaths dropped 8% percent to 3221 fatalities in the UK, some of the most substantial drops occurred in areas without speed camera partnerships at all, such as in Durham and North Yorkshire, where fatalities dropped 24% and 9% respectively. In the areas with the most speed cameras it’s a different story entirely, where the number of deaths increased substantially. In North Wales, fatalities jumped 18% and Wales overall rose 16%. Fatalities in Hertfordshire and Wiltshire grew by 34% and 22% percent respectively.

The figures speak for themselves, and when you consider that £22m profit is generated annually by speed cameras alone, it is incomprehensible to believe that these “partnerships” have been installed for our safety as opposed to clearing out our wallets. While the local authorities across the country have achieved nothing but impose a state of paranoia upon drivers, we are now spending too much time with our eyes glued to the speedometer, rather than actually concentrating on the road- inciting dangerous driving.

The simple truth is that a majority of drivers will often travel at a speed that they feel is suitable for the road they are on and the conditions of their environment. It is logical to assume that a driver will travel considerably slower on a road in heavy rain with a high volume of traffic than if they were travelling along the same road in dry conditions, clear visibility and a low volume of traffic. The fact that the limit remains the same for both conditions becomes irrelevant, which therefore begs the question – should speed limits be banned?

Abolish speed limits?

Another bold proposition you might think, but consider for a moment the entire network of Britain’s public roads without a single speed limit, and therefore- without any speed enforcement cameras. While many peoples’ immediate reaction might be to assume that everyone would suddenly start racing down every road in an attempt to set a new land speed record, the effects would in fact be much more subtle, and yet increasingly effective in preventing road fatalities. Instead of millions of drivers looking out for unmarked police cars sneaking up behind them or staring at their speedometer to ensure they’re not travelling a deadly 71mph on a motorway, we would all actually be concentrating on the road in front of us. What a refreshing change.

There would be no more panic braking upon the approach to a speed camera, because there would no longer be any. The motoring writer LJK Setright, who sadly died a few weeks ago, once wrote, “Speed limits cannot be justified. Logically, there should be only one motoring offence, dangerous use.” The local authorities could re-concentrate their efforts to catch actual dangerous drivers by targeting those without a valid MOT or insurance, who are escaping detection far too easily.

For the meantime however, while the government continue to manipulate statistics and target Britain’s motorists it seems like little is due to change to work towards fairer motoring and safer roads…especially when £22,000,000 is on the end of it all. How strangely ironic"...

In allowing me to post this here it is understood; Robert's views and opinions are expressed as his own and LOC neither endorses or necessarily agrees with the statements made. LOC disclaims any and all liability for the views expressed in by Robert inthis article.

[Zee007]

Great article.

[Monster-Mat]

i agree 100% with everything in that article

sadly the govnt cares not for our safety, but more for our money

[Jiberjaber]

- The conditions on the road (dry, wet, icy etc)

-- The volume of traffic on the road (congested, moderate, quiet)

- Visibility conditions (foggy, day, night, storm etc)

The above factors are all measureable (and are measured) on UK roads. There are also trials for headway measurement and enforcement in the pipeline...

What the writer also doesn't acknowledge is the design speed for roads in terms of sight lines, cambers, undulations, surface material and the impact speeds used in the structure calculations when designing and constructing roads and their associated infrastructure.

As an example, if the worst happens and you end up in trouble at speed, would you rather be:

A. deccelerating from 70mph into a crash barrier that is designed around that impact speed to crumple and stop you joining the oncoming traffic;

B. or would you rather be at 100mph deccelerating into the same crash barrier with a considerably less chance of being restrained within the same carriageway as your original direction of travel ?

I know which side of the speed limit I would want to be on in the above example.

If you’re travelling at 78mph down the M4 you had best watch out

If your doing 78 off your speedo, in most cases you will be actualy somewhere around the 72 mph mark in real speed and very unlikly to become a target for the poilse unless you are doing something silly (too close to the car in front for example)....

If your doing 78mph actual.. it is most likly that you were doing an indicated 85 - 90 mph on the speedo... thats a bit silly then isn't it! You then know your speeding and accept teh risk and consequences.... it always makes me laugh when I see a complaint about getting done for speeding at something like that when in fact the perp KNEW they were over the limit and what they may expect... playing with fire and not expecting to get burnt!

/high horse mode off....

[Monster-Mat]

- The conditions on the road (dry, wet, icy etc)

-- The volume of traffic on the road (congested, moderate, quiet)

- Visibility conditions (foggy, day, night, storm etc)

The above factors are all measureable (and are measured) on UK roads. There are also trials for headway measurement and enforcement in the pipeline...

What the writer also doesn't acknowledge is the design speed for roads in terms of sight lines, cambers, undulations, surface material and the impact speeds used in the structure calculations when designing and constructing roads and their associated infrastructure.

As an example, if the worst happens and you end up in trouble at speed, would you rather be:

A. deccelerating from 70mph into a crash barrier that is designed around that impact speed to crumple and stop you joining the oncoming traffic;

B. or would you rather be at 100mph deccelerating into the same crash barrier with a considerably less chance of being restrained within the same carriageway as your original direction of travel ?

I know which side of the speed limit I would want to be on in the above example.

If you’re travelling at 78mph down the M4 you had best watch out

If your doing 78 off your speedo, in most cases you will be actualy somewhere around the 72 mph mark in real speed and very unlikly to become a target for the poilse unless you are doing something silly (too close to the car in front for example)....

If your doing 78mph actual.. it is most likly that you were doing an indicated 85 - 90 mph on the speedo... thats a bit silly then isn't it! You then know your speeding and accept teh risk and consequences.... it always makes me laugh when I see a complaint about getting done for speeding at something like that when in fact the perp KNEW they were over the limit and what they may expect... playing with fire and not expecting to get burnt!

/high horse mode off....

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yeah yeah just protecting your intrests :)

Edited September 29, 2005 by Monster-Mat

[jasper]

Arnt the speed limits in use today been the same for a large number of decades? before technological advancements in car safety such as abs etc.

I

[Jiberjaber]

Arnt the speed limits in use today been the same for a large number of decades? before technological advancements in car safety such as abs etc.

I

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Unfortunatly, that doesn't make the concrete any softer to crash in to or hold the bridges up when you take out their supprts :)

[Jiberjaber]

... stuff ....

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yeah yeah just protecting your intrests :)

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Yes Matt :P

[eXOBeX]

As an example, if the worst happens and you end up in trouble at speed, would you rather be:

A. deccelerating from 70mph into a crash barrier that is designed around that impact speed to crumple and stop you joining the oncoming traffic;

B. or would you rather be at 100mph deccelerating into the same crash barrier with a considerably less chance of being restrained within the same carriageway as your original direction of travel ?

There'll be design factors implemented that mean that the barriers will take impact speeds well in excess of 70mph. For example, a bridge with a 3.5 ton weight limit is more likely to be designed to take 6 or 7 tons - a 3.7 ton van ain't going to go through the floor of it!

I don't think speed limits should be abolished altogether, but perhaps the "national" speed limit should be an "advisory" one rather than an "enforced" one - certainly on motorways and dual carriageways - where the majority of us exceed the limit anyway - and also on "long, straight stretches" of single carriageways, where 85mph on a nice, quiet night isn't actually an "offence" as there's nobody about to offend!

Another possible option would be raised limits for those who have passed an advanced driving test. For example, 70mph limit on motorway for "normal" drivers, raising to 100mph for those who've passed their advanced test. Catch someone doing 90mph, PNC check reveals an advanced driver, so no offence recorded. This would encourage more people to take up advanced driving courses and allow them to be not just faster drivers, but SAFER drivers.

[Jiberjaber]

As an example, if the worst happens and you end up in trouble at speed, would you rather be:

A. deccelerating from 70mph into a crash barrier that is designed around that impact speed to crumple and stop you joining the oncoming traffic;

B. or would you rather be at 100mph deccelerating into the same crash barrier with a considerably less chance of being restrained within the same carriageway as your original direction of travel ?

There'll be design factors implemented that mean that the barriers will take impact speeds well in excess of 70mph. For example, a bridge with a 3.5 ton weight limit is more likely to be designed to take 6 or 7 tons - a 3.7 ton van ain't going to go through the floor of it!

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Nope, your thinking about the actual bridge deck, I am taking about the bit that holds the bridge up.... take a 7.5t van going at 70 mph hitting the leg of a bridge for example.

Even the 1.5m x 2m concrete sections of the M25 have been known to stuggle to contain a HGV when it has tried to cross the carriageways...

Remember it is the impact load I am talking about, not the load the structure can carry. For example, you might design a gantry leg to take the impact of a standard car at 70 mph, that means to increase the speed limit on that section of road, the structures would need a large investment in protection from impact - not going to happen I think. This is an element from the equation often missed in articals such as the one at the beginning of this thread.

[star a]

Arnt the speed limits in use today been the same for a large number of decades? before technological advancements in car safety such as abs etc.

I

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Unfortunatly, that doesn't make the concrete any softer to crash in to or hold the bridges up when you take out their supprts :)

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edt see exobex link for 70mph history edit

of course the speed you are travelling when you crash has a huge bearing on the damage caused at impact, so 70 is not a magical safe figure, why not 60, why not 50, after all these are safer speeds.

a typical saloon from the early 70's would fare far far worse if it got into trouble at 70mph than even the most basic cars of today, and as the majority of cars on todays roads are modern, disc braked, abs equipped, airbagged, crash tested it is unfair to use a limit introduced 30yrs ago.

to me, an advisable limit of 70,60, 50 or whatever is fine, with the offence of dangerous driving, should the driving conditions become unsafe to travel in excess of the advisable limit, such as high traffic volumes (e.g. rushhour), heavy rain, freezing conditions, fog etc.

cars don't suddenly crash beyond 70, it is usually travelling too close, lack of observation when changing lanes including lack of signalling, it can be argued that a lower speed would help avoid crashes during those situations, well yes it would, but should we drive at 50 or less to further reduce accidents caused by the above..

or should the erratic lane changers, non signallers and tailgaters be more forcefully targetted, and perhaps then we can spend more time looking at the road when we are driving, and not the speedo, gatso, hidden van etc etc.

(to knock a mway bridge support out would take a incredible amount of mass, they are designed to take an impact from a 44t hgv, so i wonder how fast a car would need to travel to create the same mass at impact.)

[crazylex]

Arnt the speed limits in use today been the same for a large number of decades? before technological advancements in car safety such as abs etc.

I

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Unfortunatly, that doesn't make the concrete any softer to crash in to or hold the bridges up when you take out their supprts :)

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the 70mph motorway limit was introduced to help conserve fuel during the fuel crisis of the early seventies, and helped along the way by a few e-type owners driving at 150mph down the m1.

of course the speed you are travelling when you crash has a huge bearing on the damage caused at impact, so 70 is not a magical safe figure, why not 60, why not 50, after all these are safer speeds.

a typical saloon from the early 70's would fare far far worse if it got into trouble at 70mph than even the most basic cars of today, and as the majority of cars on todays roads are modern, disc braked, abs equipped, airbagged, crash tested it is unfair to use a limit introduced 30yrs ago.

to me, an advisable limit of 70,60, 50 or whatever is fine, with the offence of dangerous driving, should the driving conditions become unsafe to travel in excess of the advisable limit, such as high traffic volumes (e.g. rushhour), heavy rain, freezing conditions, fog etc.

cars don't suddenly crash beyond 70, it is usually travelling too close, lack of observation when changing lanes including lack of signalling, it can be argued that a lower speed would help avoid crashes during those situations, well yes it would, but should we drive at 50 or less to further reduce accidents caused by the above..

or should the erratic lane changers, non signallers and tailgaters be more forcefully targetted, and perhaps then we can spend more time looking at the road when we are driving, and not the speedo, gatso, hidden van etc etc.

(to knock a mway bridge support out would take a incredible amount of mass, they are designed to take an impact from a 44t hgv, so i wonder how fast a car would need to travel to create the same mass at impact.)

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Actualy I thought the M1 speed limit was brought in to stop car manufacturers using it as a speed test track - such as the AC Cobra -

I could be wrong but its what I heard

[eXOBeX]

Nope, your thinking about the actual bridge deck, I am taking about the bit that holds the bridge up.... take a 7.5t van going at 70 mph hitting the leg of a bridge for example.

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The bridge was just an example of design factors at work. They do test bridge designs by trying to take the legs out with lorries, etc. - saw a clip on TV a while back.

My point was that the crash barriers are already going to be designed to take speeds well in excess of 70mph, increasing the limit shouldn't push top speeds up to the point where the barrier's rating is exceeded.

Interesting ABD article here about motorway speed limits.

[Jiberjaber]

Take a look at the following document (DMRB Vol 1, BD60/04), specificaly appendix B for a view on the damage caused by impact from HGV's

http://www.archive2.official-documents.co....ect3/bd6004.pdf

Irrespective of why or when speed limits were introduced on roads, the design of the surrounding furniture is with a speed limit in mind. It is a simple fact that the faster you are going, the more energy you will impart on what ever you hit (Newton knew a few things I guess :) )...

All I was refering to was the fact that these design requirements (and others) are convieniently forgot when it comes to some articals regarding speed limits.

I am sure there is another section of the DMRB relating to speed and design but I can't find it and I am not at work so if you want to look for further info, take a look over at:

http://www.archive2.official-documents.co..../dmrb/index.htm

:)

/unsubscribes before I get into some silly argument about speed limits :)

[MrADeveci]

/unsubscribes before I get into some silly argument about speed limits :)

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I'll protect you mate, i'm on your side ! ..........

[MacRS200]

When I went to school Kinetic Energy = Mass x Velocity Squared.

So a 44 ton lorry travelling at 60 MPH would have 158,400 units of energy.

Therefore a 1.75 ton car would have to be travelling at 300 MPH to have the same amount of Kinetic Energy!

edit - Just checked and it is actually 1/2 x M x V squared. Makes no difference result is still 300 MPH

Edited September 29, 2005 by MacRS200

[Jiberjaber]

Interesting ABD article here about motorway speed limits.

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Interesting article, but no reference to where the 85th percentile speed were measured or when and also not a mention regarding the costs associated with the design issues.....

[star a]

i don't think it would be possible in any car to drive at such a speed as to equate the energy of a 60 mph 44t HGV hitting a concrete bridge support. (we are talking about speed limits for cars here, right?)

edit must learn to type faster

[MacRS200]

i don't think it would be possible in any car to drive at such a speed as to equate the energy of a 60 mph 44t HGV hitting a concrete bridge support. (we are talking about speed limits for cars here, right?)

edit must learn to type faster

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Like I said above about 300 MPH

[Jiberjaber]

Granted a car is not going to take out a bridge leg, but it could do sufficient damage to require replacement.... any one remember the effect of the last two fires under bridges on the M25 at Junction 9? This is a fire of course, but the effect of remedial works on the structure for two weeks was terrible....

Won't someone think of the children!

The impact at speed is just one of the design factors.... there are plenty of others including how cars can react to road subsidence etc.... it all needs to be taken into account, but non of the reports or articles I have seen to date have.. so they are nothing more than just half the story IMHO....

Alowing the speed limit to be raised on the basis of a small percentage of drivers who are capable of driving at those speeds is also a silly idea... but then, who would be able to prove their compentance? Will we need race driver licences to drive at a new higher speed? Remember to problem of the in experianced driver who will just pull out or the twunt on the mobile who doesn't check over the shoulder before pulling out 2 mile before they actualy get within 500m of teh vehicle they want to over take.... how are they going to react to a faster speed limit...

We all think we can drive safe, or what conditions are safe, but do we actuallly know, how are we qualified to make that decision?

Speed limits always cause loads of discussion, enjoy :)

[Matthew_McNally]

I do not agree with speed cameras at all.

I do not see how having drivers spend more time looking at their speedometers than the road is preventing accidents.

However, I have an issue with any idea that involves MY safety relying on the good judgement of others - especially as the majority of the people supporting this are relying on spurious arguments to support their base - but unspoken - requirement.

THEY WANT TO DRIVE FASTER.

I dont care if it takes 15 men three moths to scrape the decaying remains of YOUR corpse off the road, because you crashed your car into the barrier at 180mph.

I do however care that it is not ONLY you who can be involved in these accidents.

Why should I, my family, friends and loved ones be put at risk because someone felt that, IN THEIR ASSESMENT, 130 mph was a suitable and safe speed?

[star a]

Like I said above about 300 MPH

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yeh i know

[MacRS200]

To be serious I regularly drive a section of the A10 with numerous junctions, crossings, farm tracks, tractors and even combine harvestors. The limit is 70.

Yet I can be on a deserted motorway at 03:00 with 10 miles to the next junction and the limit is the same.

Makes sense to me

[Matthew_McNally]

Yet I can be on a deserted motorway at 03:00 with 10 miles to the next junction and the limit is the same.

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have you reserved the road for your exclusive use?

[Jiberjaber]

When I went to school Kinetic Energy = Mass x Velocity Squared.

So a 44 ton lorry travelling at 60 MPH would have 158,400 units of energy.

Therefore a 1.75 ton car would have to be travelling at 300 MPH to have the same amount of Kinetic Energy!

edit - Just checked and it is actually 1/2 x M x V squared. Makes no difference result is still 300 MPH

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Bah.. I have better things to do tonight ;)

Force = Mass x Acceleration [Newtons second law]

acceleration = change in speed / time duration.

Therefore...

Force = mass x (change in speed / time duration).

If we assume a 44t HGV (44,000kg) and a speed of 50mph (22m/s) and an estimated time for deceleration to zero of .5 of a second, then...

The force on impact is just under 2,000kN (1,936,000 Newtons).

From the DMRB BD60/04 Table 4, load parallel to the carriage way during a collision is taken to be 500kN.

For an IS200 based on a mass of 1850Kg, same decelleration time, the force of collision would be:

50mph - 81kN

70mph - 114 kN

90mph - 145 kN

100mph - 166kN

So Yes, you would need to be going 300mph (135m/s) to create the required force :)

Of course I am NOT a structural engineer so my interpretations may be a bit off. :)