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Adrian

 

We have always said that there should be exceptions decided by the local authority. These should be based upon the "needs of vulnerab;e road users" as required by the general speed limit setting guidance. The council would take account of type of road users, nature of road, casualty history, segregated provision, etc and hence make a decision.

 

However the fact that a road is an A or B road should not dictate that the needs of vulnerable road users should not be taken into account. The DfT guidance only excepts "major through routes".

 

Neither should the fact that a bus company chooses a road for a bus route. Buses need to be supportive of communities and in any case only exceed 20mph currently for a small part of their journey. In peak times it is even less. In fact 20mph limits help buses through both better economy and by reducing the differential speed between buses and other motor vehicles.

 

Whether a route is strategic or no depends on the road user. For children the route to school is fairly strategic, hence their needs as a pedestrian or cyclist need to be taken into account.

 

Short roads between 30mph road can often be rat-runs and therefore speed on these should be reduced if it is a residential road.

 

So, exceptions are fine as long as they are "considered" exceptions.

 

I trust that this explains our "position" but as we have said the exceptions are a decision and responsibility for the local authority.

 

Best regards

 

 

 

Rod

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Wolfie

 

We have already had that discussion:-

 

http://www.20splentyforus.org.uk/BriefingSheets/pollutionbriefing.pdf

 

Rod

 

Rod

 

Question.... I mentioned (jokingly) about all the fumes messing with my brain earlier today after my mistake and appology to you.

 

So the following sort of jumped out at me on your link

 

Research from the ETA6 found that cyclists and walkers face pollution levels two thirds lower than inside a car. Drivers and their passengers face three times more fumes because they sit in the pollution tunnel in the centre of the road, breathing poisons from vehicles in front.

 

However when I looked at the bottom it says the findings of ETA6 were actually from 1997. That was 15 years ago?

 

Have more recent analysys been carried out and the findings from 15 years ago compared with these ? Obviously far more of the cars on the roads today are more environmentally friendly than they were 15 years ago and also car MOT's now have tests to measure emmission levels whereas they didn't used to have.

 

Just though I'd ask before I put my air fed mask on tomorrow morning incase the traffic through town and at Bridge Foot is going at 2mph again.

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I am fed up with this ridiculous subject. most of the "statistics" quoted by the "biased expert" are rubbish . They are based on false data and guesswork.

 

However it does prove the madmen have taken over.

 

Whal

 

Are you refering to the IAM "statistics". I think you will find that it was Baz who quoted from the IAM press release and all I did was provide the AIM statistics behind the press release. I am not quite sure how you reason that they are "rubbish". Can you add a little bit more depth to your argument perhaps?

 

Thanks

 

Rod

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Research from the ETA6 found that cyclists and walkers face pollution levels two thirds lower than inside a car. Drivers and their passengers face three times more fumes because they sit in the pollution tunnel in the centre of the road, breathing poisons from vehicles in front.

 

Well that is complete and utter nonsense Rod..... How can you claim against facts that are based on research carried out in 1997? I can absolutely guarantee that if you sat in my car in traffic, you would not smell or have any effect from the fumes of the car in front....

 

Even the last point about CO2 is based on data from 1998!!!

 

Your first points are based on the assumption that drivers drive and choose the gear most suitable for the situation they are in.... I would counter that is not the case (even automatics have sport and comfort settings which means the sport mode does not change until the revs are at 3000).... Have you approached any car manufacturers to get their data on whether more or less polution is generated at 20mph or are these just taken from studies by "Experts"?

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Dizzy

 

You win your "brownie point" back by actually reading the link. Thank you. It is sometimes ludicrous when someone implores you to "give them the evidence" and then when you do either does not bother to follow up the link or claims that Statistics are all lies!".

 

Your point about pollutants inhaled by different road users is a good one. Certainly other research has been done which lowers the difference between car passenger and cyclist or pedestrian. But the major point is that pollutant levels are very much on par and just because you are in a car then you are not in some magic bubble that protects your from pollutants. And of course when traffic is stopped then car occupants have to keep breathing whilst stationery, whereas cyclists and pedestrians just keep on moving and don't stay in the "jam".

 

Most reports have stated that the physical health benefits from cycling far outweigh any disbenefits due to pollutants in congested traffic. And of course in Warrington for most cycle journeys then the amount of time they are in stationery traffic is minimal.

 

And every additional cyclist you see is one less engine for you to inhale even if you are sitting in a car.

 

Best regards

 

 

Rod

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Adrian

 

As I have said, it should all be based upon the road usage, layout, casualty history, benefits from going faster (or otherwise), capacity of road at higher or lower speeds, existence of segregated cycle and pedestrian facilities.

 

If you can provide me with all of these then I can give an opinion.

 

In fact if you can provide all of these then you can probably work it out for yourself as well.

 

Regards

 

 

 

Rod

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Baz

 

You said

 

I can absolutely guarantee that if you sat in my car in traffic, you would not smell or have any effect from the fumes of the car in front....

 

Clearly you do actually have a car which forms a complete and magical bubble that does not allow any air into the car. What happens when you use up all the oxygen within the car? Do you have oxygen cyclinders so that you don't have to take the air in from outside, or maybe some special way of selecting which air comes into the car.

 

Of course you are affected by the pollution outside. You don't "smell" it because you are so used to it.

 

 

Regards

 

 

Rod

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Baz

 

Your first points are based on the assumption that drivers drive and choose the gear most suitable for the situation they are in.... I would counter that is not the case (even automatics have sport and comfort settings which means the sport mode does not change until the revs are at 3000)....

 

So are you suggesting that it is sensible to set your automatic gearbox to "sport" when in a residential area? Or do you think that speed limits should be set higher than is sensible because some drivers do not know how to select the correct gear?

 

The car manufacturers have long ago given up providing any really useful information on what their cars emit and consume.

 

Regards

 

Rod

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Baz

 

You said

 

 

 

Clearly you do actually have a car which forms a complete and magical bubble that does not allow any air into the car. What happens when you use up all the oxygen within the car? Do you have oxygen cyclinders so that you don't have to take the air in from outside, or maybe some special way of selecting which air comes into the car.

 

Of course you are affected by the pollution outside. You don't "smell" it because you are so used to it.

 

 

Regards

 

 

Rod

 

You've been wearing the Lycra for too long Rod.... Modern cars have things that stop a lot of the nasty stuff called cabin air filters.

 

Most of today’s cabin air filters trap odours and are the charcoal activated cabin filters. These filters also have an extra layer of activated carbon that reacts with odours and other airborne pollutants to neutralise them before they enter the vehicle.

 

The charcoal activated filters will also reduce the levels of carbon monoxide and Nitrous Oxide from the emissions of other vehicles on the road.

 

"For example; vehicles that do not have a carbon activated filter and are in rush hour traffic, will have up to three times the carbon monoxide levels inside the vehicle than outside."

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Baz

 

So are you suggesting that it is sensible to set your automatic gearbox to "sport" when in a residential area?

 

Did I say that? Or are you twisting what I said to hide the fact that most of your arguments are flawed at best and utter nonsense at worse?

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do you think that speed limits should be set higher than is sensible because some drivers do not know how to select the correct gear?

 

The car manufacturers have long ago given up providing any really useful information on what their cars emit and consume.

 

The first point..... You can advise and legislate all you want, but if someone wants to leave their car in 1st or 2nd gear when driving on a 20mph road and thuis increasing their emissions..... you won't change that Rod

 

Have a look here at our emissions.... http://www.energy.eu/

 

the UK is lower than Germany on CO2 and NO2 emissions.... now is that because they have 20 limits and drive in lower gears I wonder.... Anyway, a good site and plenty to show actual emissions figures from cars so that sort of stomped on your "car manufacturers have long ago given up providing any really useful information on what their cars emit and consume" angle....

 

http://www.energy.eu/car-co2-emissions/

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Have a look here at our emissions.... http://www.energy.eu/

 

the UK is lower than Germany on CO2 and NO2 emissions.... now is that because they have 20 limits and drive in lower gears I wonder.... Anyway, a good site and plenty to show actual emissions figures from cars so that sort of stomped on your "car manufacturers have long ago given up providing any really useful information on what their cars emit and consume" angle....

 

http://www.energy.eu/car-co2-emissions/

 

I think that these are "total emissions" of which transport is probably about 20%. Have you got the figure for motor vehicle emissions per head or per mile travelled? Have you included miles travelled by cycle as well?

 

As you will see the CO2 emissions from the car manufacturuers are a single figure and not broken down into emissions per mile at different speeds or per second of acceleration. Now that would be useful, but is never provided.

 

 

Regards

 

Rod

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Have you got the figure for motor vehicle emissions per head or per mile travelled? Have you included miles travelled by cycle as well?

 

The emissions per km are provided as part of all manufacturer data. I'm sure the clever ones out there can convert it to the proper units of miles easily enough....

 

 

As you will see the CO2 emissions from the car manufacturuers are a single figure and not broken down into emissions per mile at different speeds or per second of acceleration. Now that would be useful, but is never provided.

 

If the data is never provided by the manufacturers and never independantly tested to give such data, how do you come to your opinions that driving at 20mph produces less emissions than at 30?

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Emissions vary so much from car to car, age of car, how they are driven, maintained, what type of fuel they use and 101 other factors that it would be impossible to list a single figure for all cars broken down per mile at different speeds.

 

Interesting link here where the AA say that cutting speed limits on the wrong roads from 30 to 20 may actually increase CO2 emmissions by more that 10% and average petrol fuel consumption on longer and relatively free-flowing 20mph urban streets can worsen by 5.8 miles per gallon.

 

I said WRONG roads Rod by the way and this does not include tiny little residential streets before you tell me off.

 

I will be steering clear of speed bumps from now on though as fuel consumption and emmissions seem to rocket with them :blink:

 

The AA - 20 mph Lower limits can increase fuel consumption and CO2 emissions

 

Anyway sod emissions, I don't really care and I can't see the relevance in our area anyway.....whether it's 20, 30, 40 or 60 there will still be as many cars on Warrington's roads.

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The emissions per km are provided as part of all manufacturer data. I'm sure the clever ones out there can convert it to the proper units of miles easily enough....

Durh stupid me re my last post... you are right Baz.

 

All the levels for all petrol cars registered after 1992 have to conform to the manufacturers spec like you say and all the figures and specs for evert vehilce and it's various nasty emmissions like CO2, hydrocarbon etc are stored on a big database as MOT testing stations use them when they do MOT's.

 

Diesel cars are different though and I think they are just tested for smoke output but I could be wrong.

 

Rod, did you know that Diesel cars have much lower CO2 emissions than petrol cars so are much better for global warming... but they give off far more NOx and nasty particulates so are worse for local polution and health. I learnt that a few months ago when I had to compile some H&S info.

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The fact that CO2 and other emissions vary from car to car is irrelevant and something that is not at the top of rod's priority list.

 

Reducing the speed limit from 30 to 20 will result in higher emissions and higher fuel consumption, so whatever the levels are in near gridlocked Warrington, we can looked forward to even higher levels.

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The emissions per km are provided as part of all manufacturer data. I'm sure the clever ones out there can convert it to the proper units of miles easily enough....

 

 

 

 

If the data is never provided by the manufacturers and never independantly tested to give such data, how do you come to your opinions that driving at 20mph produces less emissions than at 30?

 

Baz

 

I was referring to the CO2 emissions per country which you were using and comparing UK with Germany.

 

With regard opinions regarding fuel and emissions at 20mph, 30mph and accelerating between the two I used the laws of physics and a few ideas put together by Isaac Newton. They may be rather old but seem to stand the test of time. Its rather obvious really. Kinetic Energy at any speed is 1/2 mv2. So the energy required to reach 30mph is 2.5 times that needed to reach 20mph. Hence it takes 1.5 times as much energy to go from 20 to 30 as it does from 0 to 20mph.

 

Also reference to the research by Peter de Mayer and the Telegraph report which I have referred to before in this thread.

 

Oh, and a degree in Automobile Engineering comes in handy as well.

 

Best regards

 

 

Rod

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