30k speed limits for all urban areas on the way

railer201 · 22-07-2022 02:40PM

https://www.boards.ie/discussion/comment/119372166#Comment_119372166

It has also been amply proved in physics that if you double the flow rate of water through a pipe, twice the amount of water will pass from A to B in any given time. It is the same with traffic flow, or anything that flows for that matter.

It is a nonsense to suggest that slowing down of anything, somehow speeds it up.

magicbastarder · 22-07-2022 02:47PM

https://www.sydney.edu.au/business/news-and-events/news/2018/12/21/does-slower-driving-make-us-go-faster-.html

water pipes don't have traffic lights or crossing traffic, or have to deal with the reaction times of the water molecules etc.

your comparison with water pipes is to trivial as to be useless.

22-07-2022 02:53PM

https://www.boards.ie/discussion/comment/119372918#Comment_119372918

Traffic flow can not be equated with water flow

Its insane that this has to be pointed out

Unrealistic · 22-07-2022 04:11PM

https://www.boards.ie/discussion/comment/119372918#Comment_119372918

Did you even read the post? Water does not flow in individual molecules that try to avoid contact with one another and leave a larger gap between themselves and other water molecules the faster they move. It's an idiotic comparison.

SeanW · 22-07-2022 06:09PM

https://www.boards.ie/discussion/comment/119369429#Comment_119369429

How many fatalities and injuries were there in this incident? How does this one incident justify punishing 2.5 million people with stupid, excessive, punitive "crawl everywhere" laws?

https://www.boards.ie/discussion/comment/119362274#Comment_119362274

In large part yes, Ireland has changed a lot since 1997, and from what I understand the school "system" at best has struggled to keep up. If you're not taking that into account with your glib analyses, you aren't looking at the whole picture.

If you don't like the number/percentage of students being drive to school, you should be asking yourself why so many students and families have to make their own travel plans to school. That might be a little more illuminating than crapping on people for making choices you don't like, which may well be a symptom of a larger problem more than anything else.

AndrewJRenko · 22-07-2022 06:48PM

https://www.boards.ie/discussion/comment/119372466#Comment_119372466

Afaik, as long as you’re not holding or supporting the phone, you’re good. So tapping out a text on a dash mounted phone- no problem. Video chat with your missus on a dash mounted phone- fire away. Catch up on your Netflix binge on dash mounted phone- it’s all good.

AndrewJRenko · 22-07-2022 07:31PM

https://www.boards.ie/discussion/comment/119374062#Comment_119374062

The 2014 SI specifically refers to SMS and MMS messages only, so it doesn’t include WhatsApp or Signal or others.

https://www.irishstatutebook.ie/eli/2014/si/178/made/en/print

The 2006 laws block holding or supporting the phone with any part of the body.

https://www.irishstatutebook.ie/eli/2006/act/23/section/3/enacted/en/html?q=Mobile+phone+hold+or+support+part+body+&search_type=all

harmless · 22-07-2022 09:57PM

Has this been tested in the courts? I don't think I've heard of anyone getting penalty points unless they had the phone held in their hand.

railer201 · 22-07-2022 10:05PM

https://www.boards.ie/discussion/comment/119373419#Comment_119373419

Put your money where your mouth is.

Try driving yourself at 30 kph in the 50 or 60 kph zones and see how quicker your journeys go ? Don't restrict your trips to rush hour, pick some off peak times too.

Let's know how you get on !

hairymaryberry · 23-07-2022 01:52AM

Would bet a weeks wage when it come in not a single DB/GA route will get a new roster to allow for the extra running time.

Remember this post when the 30kph limit comes in and your bus has gone missing, dont automatically blame DB/GA, blame the NTA and there out of date timetables

Unrealistic · 23-07-2022 01:12PM

https://www.boards.ie/discussion/comment/119374810#Comment_119374810

You clearly still don't get it. The exact words I wrote were:

"Yes, it has been shown that lower speeds can reduce congestion because they allow greater throughput. If I remember correctly 40km/h is the sweet spot where you can get the most cars through a given stretch of road in a given time period."

Reducing congestion is not the same as reducing journey times. It means more people/vehicles get moved from A to B in a given time period. Just as an example (numbers pulled out of the air but, from memory, they're not far off) if you stand at fixed point on a road where cars are driving past at a steady 70kmh and counted all the cars that passed in the space of one minute, and then a 40kmh speed limit is enforced and all cars are now driving at that steady pace, more cars will pass now you in the space of one minute as the gap between the cars will be much smaller.

So your suggestions that I drive around at a specific speed, while all other vehicles are trying to reach higher speeds, would prove nothing as it is completely unrelated to the scenario I outlined. Neither would driving at off-peak times when my whole point was about the impact on congestion.

railer201 · 24-07-2022 10:00AM

Quote - Unrealistic "So your suggestions that I drive around at a specific speed, while all other vehicles are trying to reach higher speeds, would prove nothing as it is completely unrelated to the scenario I outlined."

Why not start now before these laws come into being and do your bit for traffic congestion ? You're the one that has claimed a greater throughput of traffic due to the gaps being reduced between the travelling vehicles at the 'sweet spot' of 40 kph. So why not try it is what I'm asking - the vehicles behind you should bunch up, the result being more vehicles passing a given point, thereby reducing the congestion.

Anyway, consider congestion for a minute. The new proposed 'crawl' limit of 30 kph - I hesitate to use the term 'speed' here - will serve only to increase average journey times which in turn reduces the overall 'throughput', which in turn increases the congestion you mention. The only real debatable point is by how much ?

magicbastarder · 24-07-2022 10:09AM

the throughput of a road is not directly linked to the speed of the cars driving on it; and it's a lot to do with the fact that you would (should!) generally fit fewer cars on a road when they're moving faster.

if everyone drives according to the two second rule, and you stand at the side of the road, counting cars; the same number of vehicles will pass you in a set time. 30 a minute per lane. even though vehicles in a motorway lane would be moving at speeds several times faster than those on a suburban road, it is no more efficient at moving those cars around in terms of actual throughput. start throwing in multiple traffic lights and junctions, and the supposed linear relationship between speed, journey time, and road capacity is a distant dream.

AndrewJRenko · 24-07-2022 08:16PM

https://www.boards.ie/discussion/comment/119374804#Comment_119374804

Judges have this funny habit of leaving it to the Oireachtas to legislate, and not filling in gaps themselves, as they know that the legal eagles will just appeal it to a higher Court and get the decision overturned. The SMS / MMS are explicitly defined in legislation, so unless you can find a way to equate a Whatsapp message to 'email', then it wouldn't be covered. Neither would watching Netflix, or having a video chat, or playing YouTube videos.

Flinty997 · 26-07-2022 11:32AM

https://www.boards.ie/discussion/comment/119372918#Comment_119372918

Are you sure...

At a given temperature, flow rate through a tube or pipe is inversely proportional to the length of the tube the viscosity of the liquid. Flow rate is directly proportional to the pressure gradient and the fourth power of the radius of the pipe.

Applying Poiseuille's Law

Even when turbulence is a factor, you can still use Poiseuille's equation to get a reasonably accurate idea of the how flow rate changes with pipe diameter. Keep in mind that the stated size of a pipe is a measure of its diameter, and you need the radius to apply Poiseuille's law. The radius is half the diameter.

Suppose you have a length of 2-inch water pipe, and you want to know how much the flow rate will increase if you replace it with 6-inch pipe. That's a change in radius of 2 inches. Assume the length of the pipe and the pressure are constant. The temperature of the water should also be constant, because the viscosity of water increases as the temperature decreases. If all these conditions are met, the flow rate will change by a factor of 24, or 16.

Flow rate varies inversely to length, so if you double the length of the pipe while keeping the diameter constant, you'll get roughly half as much water through it per unit of time at constant pressure and temperature.

https://sciencing.com/flow-rate-vs-pipe-size-7270380.html

Flinty997 · 26-07-2022 11:47AM

https://www.boards.ie/discussion/comment/119379381#Comment_119379381

You're actually wrong.

Higher speed limits only slightly reduce travel time, over long distances.

For example, raising the speed limit from 100 km/h to 110 km/h will save 5.5 minutes if you are travelling 100 km (assuming there are no delays). In built up areas, time savings from higher speed limits are hard to achieve due to the stop start nature of the journey and tend to be negligible for short journeys. In some circumstances, lower travel speeds may reduce travel times by minimizing flow breakdown.

Spook_ie · 17-08-2022 07:51AM

Unlikely to occur but wouldn't it be lovely and much easier to check speeds of ALL traffic

https://news.sky.com/story/cyclists-could-face-speed-limits-and-may-need-number-plates-reports-say-12674899

magicbastarder · 17-08-2022 07:58AM

how does he propose to enforce speed limits on a vehicle which does not have a speedometer, and is not legally required to have one? are they going to subsidise supply of a GPS unit to all cyclists?

it's a farcical suggestion.

17-08-2022 08:18AM

https://www.boards.ie/discussion/comment/119483733#Comment_119483733

It is a joke. He’s being ripped apart by radio commentators this morning that he’s come out with this while airports are in chaos, there’s a trucking crisis and train strikes almost weekly

It’s an impossibility to enforce anyway and will never happen. The guy is a moron

Spook_ie · 17-08-2022 05:16PM

https://www.boards.ie/discussion/comment/119483733#Comment_119483733

In 1935 a 30 mph limit was introduced in the UK for urban areas, it wasn't until 1937 that speedometers became compulsory, so not having a speedometer or the legal requirement to have one were not not originally linked to having a speed limit.

AndrewJRenko · 17-08-2022 08:21PM

https://www.boards.ie/discussion/comment/119483720#Comment_119483720

What problem would it solve, in terms of road deaths and injuries?

It's designed as a distraction for gammon Mail readers from the farcical leadership election, if you hadn't yet worked that out.

Your 'wouldn't it be lovely' is like to ramp up the abuse and intimidation that cyclists get on the road.

magicbastarder · 17-08-2022 08:46PM

https://www.boards.ie/discussion/comment/119486124#Comment_119486124

you're quoting an 87 year old precedent. things have moved on a teensy bit since then.

Spook_ie · 17-08-2022 10:50PM

I'm merely pointing out that there was a time when not having a speedometer didn't prevent you from being prosecuted for exceeding a speed limit.

Nothing to say that it couldn't be brought back in some form for cyclists, e-cyclists and e-scooters

magicbastarder · 18-08-2022 09:15AM

https://www.boards.ie/discussion/comment/119487335#Comment_119487335

yes; again, for two years. 87 years ago. in a different jurisdiction.

recently, there was an attempt to bring in a law which made passing a cyclist with less than 1m or 1.5m (depending on the speed) room to spare. the AG advised, quite explicitly, that it was creating an unworkable burden of proof in that there was no way to actually measure the distance between car and cyclist, certainly not in a court of law. this is a similar concept, creating a law around a specific metric which is not measurable by the target audience.

the notion of introducing speed limits for bikes, when a) it's a solution in search of a problem, b) there's no way for most cyclists to know for certain what speed they're doing, and c) you can damn well be sure it wouldn't be enforced (in ireland, anyway) makes it a farcical suggestion.

should we also introduce speed limits for pedestrians? i was once bumped into by a jogger. he should have been limited to 10km/h, the bounder.

Spook_ie · 18-08-2022 12:42PM

https://www.boards.ie/discussion/comment/119487972#Comment_119487972

Just because something isn't enforced doesn't in itself make it farcical, unless of course you want to include cyclists on footpaths, breaking red lights, breaking stop lines etc.

Anyways if the 30kph limit is being enforced to motorists it should be relatively easy to spot a cyclist over taking the traffic travelling in excess of the 30kph limit

There are solutions to the problems you (as a cyclist) just don't want to entertain them.

magicbastarder · 18-08-2022 01:24PM

it's not that i don't want to entertain the solutions, it's that i don't think the 'problem' really is a problem.

Larbre34 · 20-08-2022 07:44PM

The problem isn't a problem.

There is no widespread public support for a default urban limit of 30 km/h. The public consultation for the Dublin City proposals for same demonstrated that and even the normally cloud dwelling officials in Dublin City Council decided to waste no further energy on it and consign it to the bin.

21-08-2022 11:45AM

https://www.boards.ie/discussion/comment/119498886#Comment_119498886

As is usually the case, you're incorrect. The 30k limit is getting rolled out to more and more places around the country every year.

It's only a matter of time until it becomes the default limit for all cities and towns and hopefully, villages

AndrewJRenko · 21-08-2022 08:16PM

https://www.boards.ie/discussion/comment/119498886#Comment_119498886

There was no widespread public support for the workplace smoking ban, but very few people would want to go back on that now.

https://www.boards.ie/discussion/comment/119488877#Comment_119488877

What problem would this solve?

magicbastarder · 21-08-2022 08:48PM

we had a journey on friday which needed to be done in the car; bringing two rather unimpressed cats to the vet for their annual booster. from near DCU to raheny; a 17km round trip, and the appointment was at 2pm. our average speed was 22km/h, in non-rush hour traffic, and as far as i know, not a single road we drove on had a 30km/h limit, and some had a 60km/h limit; the irony was that by far the slowest section was in a 60km/h zone (we drove home past northside shopping centre/clonshaugh business park)

one thing i will repeatedly say to people who get annoyed at the notion of a 30km/h limit - you're already going slower than that. if the notion of having to drive slowly annoys you, get an e-bike or a moped. you'll go measurably faster.

30k speed limits for all urban areas on the way

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