Page 1 of 2

20 limits - 'the facts'...

Posted: Mon Oct 24, 2022 9:25 am
by martine
So I received an email from a road safety professional with the following 'facts'...what does everyone here think?

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...the below facts are sourced from the DfT, TfL and public health for England...
• Lower speed limits to be introduced in London to try and reduce road injuries and deaths

• TfL committed to reduce speed limits to 20 mph on all 220km of the TfL road network (London red routes) by 2024, in addition to the roads in the Congestion Charge zone, which have carried the lower limit since March 2020

• The lower speed limit encourages people to travel in more active and sustainable ways. Active travel – walking and cycling helps to improve health and reduce the burden on the NHS

• 20 mph zones do not appear to worsen air quality and they dramatically reduce road danger. They also support a shift to walking and cycling, generate less traffic noise and reduce community severance

• Smoother driving, with fewer accelerations and decelerations, generates fewer particulate emissions from tyre and brake wear. 75% of road transport particulate emissions come from tyre and brake wear, not exhausts

• The British Medical Journal (BMJ), report an 8% reduction in Nitrogen Oxide and PM10 (Particulate Matter) emissions for 20mph compared to 30mph in diesel cars

• Speed is a factor in at least 37% of collisions where a person is killed or seriously injured on London streets

• London Borough of Hammersmith and Fulham – Public health report:
https://www.lbhf.gov.uk/sites/default/files/section_attachments/20mph-speed-limit-public-health-report.pdf
(Evidence shows that 20mph limits significantly reduce RTAs, air pollution, noise pollution and increase physical activity. They also have the potential to reduce health inequalities. Therefore, although 20mph limits appear to offer benefits they alone do not solve all road risks.)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Re: 20 limits - 'the facts'...

Posted: Mon Oct 24, 2022 9:47 am
by jont-
martine wrote:• Smoother driving, with fewer accelerations and decelerations, generates fewer particulate emissions from tyre and brake wear. 75% of road transport particulate emissions come from tyre and brake wear, not exhausts

Time to scrap all the speedhumps then :hit:

What does the evidence say about traffic moving from 20mph roads to 30mph roads to skew the stats?

Re: 20 limits - 'the facts'...

Posted: Mon Oct 24, 2022 12:35 pm
by Triquet
Those bullet points are scraping the barrel somewhat ... I believe that 20mph can be sensible in specific cases. I live in a village where some of the internal roads could well justify 20mph, but it would simply be daft for the two main roads through the village. A blanket reduction would probably cause more accidents.

Re: 20 limits - 'the facts'...

Posted: Mon Oct 24, 2022 6:51 pm
by Strangely Brown
They forgot:

• Most people will ignore them as completely inappropriate.

Re: 20 limits - 'the facts'...

Posted: Mon Oct 24, 2022 7:12 pm
by waremark
Strangely Brown wrote:They forgot:

• Most people will ignore them as completely inappropriate.

Not what happens in London, most people now observe them.

Cameras may be set at 24, so unwise to exceed 23.

Re: 20 limits - 'the facts'...

Posted: Mon Oct 24, 2022 10:17 pm
by Strangely Brown
waremark wrote:
Strangely Brown wrote:They forgot:

• Most people will ignore them as completely inappropriate.

Not what happens in London, most people now observe them.

Cameras may be set at 24, so unwise to exceed 23.


Most of the 20s in Brighton are ignored. No camera enforcement... yet. The new scheme that allows / will allow councils to enforce 20s and keep the money will, undoubtedly, change that soon.

Re: 20 limits - 'the facts'...

Posted: Tue Oct 25, 2022 3:21 pm
by vanman
Time to scrap all the speedhumps then :hit:

What does the evidence say about traffic moving from 20mph roads to 30mph roads to skew the stats?[/quote]

Perhaps the monies gathered from speedsters over 20 will pay for the removal of the speed humps. :o

Re: 20 limits - 'the facts'...

Posted: Wed Oct 26, 2022 10:44 pm
by Discov8
waremark wrote:
Strangely Brown wrote:They forgot:

• Most people will ignore them as completely inappropriate.

Not what happens in London, most people now observe them.

Cameras may be set at 24, so unwise to exceed 23.



I drive in London every week day, that's not my experience. People only drive slowly due to congestion, if there's no camera......

Re: 20 limits - 'the facts'...

Posted: Thu Oct 27, 2022 11:35 am
by jcochrane
Discov8 wrote:
waremark wrote:
Strangely Brown wrote:They forgot:

• Most people will ignore them as completely inappropriate.

Not what happens in London, most people now observe them.

Cameras may be set at 24, so unwise to exceed 23.



I drive in London every week day, that's not my experience. People only drive slowly due to congestion, if there's no camera......

Whereas mine is the same as waremark. I regularly drive to Covent Garden in and out of such hour. Even returning late at night with very little traffic.

Re: 20 limits - 'the facts'...

Posted: Thu Oct 27, 2022 11:44 am
by Strangely Brown
Is that because they're all queued up behind you, John? ;)