Higher speed limits improve safety (sometimes)

September1

It seems that research in Denmark shows that on some roads you can save lives by increasing speed limits, I couldn't find English article but google translate can help.
http://www.jv.dk/artikel/1678058:Indland--Raad--Hoejere-hastighed-gavner-trafiksikkerheden

Apparently certain motorways part and straight country roads benefit from that.

dr.fuzzenstein

I'm sure that whoever came up with this is being burned at the stake as we speak by the road safety and green nazi brigade. (Just getting Goodwin out of the way early and, no, it doesn't mean the debate is over):p

Mc Love

I guess that depends on the type of roads they have in Denmark!?

Sobanek

https://www.youtube.com/watch?v=gpAzXqIcWzc

Isn't this safe too? :P After all, he never crashed into anyone

RIP Tevzadze

Caliden

If you're going faster you tend to concentrate more.

A team of drivers in the U.S. went for the cross country record (27 hours or something) and saw people doing all sorts in their cars from shaving to applying makeup to eating breakfast from a bowl. With an average speed of 100mph the only close call they had was when a van driver changed lane without checking his blind spot.

ironclaw

Caliden wrote: »

If you're going faster you tend to concentrate more.

A team of drivers in the U.S. went for the cross country record (27 hours or something) and saw people doing all sorts in their cars from shaving to applying makeup to eating breakfast from a bowl. With an average speed of 100mph the only close call they had was when a van driver changed lane without checking his blind spot.

http://www.32hours7minutes.com/

http://jalopnik.com/meet-the-guy-who-drove-across-the-u-s-in-a-record-28-h-1454092837

And Richard Rawlings (Of Fast N' Loud fame) did it as well.

Should probably point out that the first two were almost military like planning and the second one there is unconfirmed. The fastest official record is the first (Alex Roy) but is disputed because of the route. It took something like 3 years to plan and about 5 attempts.

Either way, you can't compare those drivers to the average. Different league entirely. My worry is if you up'd the speed limit to 160km/h for example, Joe Bloggs who can't drive at 120km/h suddenly thinks he can go even faster and results in an even bigger mess (Remembering force is squared with increasing velocity) And then you'll have those that disregard speed limits anyway ("Sure I don't agree with 120, I'll do 140 because it suits me" etc) will edge the limit even higher. And then the oblivious, that will do the limit even if its snowing, on ice with a tornado wrapping around them.

I'd be all for high limits if they along with proper driving were rigorously enforced.

joujoujou

ironclaw wrote: »

[...]

I'd be all for high limits if they along with proper driving were rigorously enforced.

^^This!^^

And proper education first. :P

keithclancy

dr.fuzzenstein wrote: »

(Just getting Goodwin out of the way early and, no, it doesn't mean the debate is over):p

I heard those tyres were terrible ... you should change them immediately :pac:

Lucena

Of course raising the speed limits will increase safety, sometimes.

If we take a hypothetical example of a stretch of motorway with a 120kph limit, which suddenly becomes 100kph just before, or just after a bend, this could cause a lot of accidents. Depending on the nature of the bend, it might be safer to just leave the limit at 120kph.

dr.fuzzenstein

I think I worked it out!
To increase safety, spend as little time driving as possible.
This can be done two ways. Don't drive at all, if you can help it, or drive faster.
Most people don't take many unnecessary journeys, what with the cost of motoring these days.
But if we raise the speedlimit, we will all get there faster and that means we spend less time on the road.
And the less time you spend on the road, the less of a chance you have of being involved in an accident.
I'm firing off an email to Uncle Gaybo as we speak, I'm expecting this to be a big hit.

dantastic

So what the article is saying is;
If the drivers find the speed of the road reasonable they are more likely to follow it.

You have the slower ones following the speed limit, they are likely to speed up to, or close to the higher speed limit.
On the other hand the ones who are going much over the speed limit are more likely to accept that the new higher speed limit is appropriate for the road and will slow down to the limit.

This is pretty ground breaking in that they realize that people are likely to follow reasonable rules and ignore stupid ones.

Caliden

dr.fuzzenstein wrote: »

I think I worked it out!
To increase safety, spend as little time driving as possible.
This can be done two ways. Don't drive at all, if you can help it, or drive faster.
Most people don't take many unnecessary journeys, what with the cost of motoring these days.
But if we raise the speedlimit, we will all get there faster and that means we spend less time on the road.
And the less time you spend on the road, the less of a chance you have of being involved in an accident.
I'm firing off an email to Uncle Gaybo as we speak, I'm expecting this to be a big hit.

Believe it or not but motorcyclists employ the same reasoning to traffic filtering (have absolutely nothing against it as it means they're taking up less space).

The reason is that the majority of motorcyclists involved in accidents are rear ended so if you keep moving (filtering) and don't stay in stationary traffic then you won't be rear ended. (or reduce your chance anyway)

I know that if I had the means/time I would learn to ride a motorcycle as I'm envious every time I'm stuck in traffic (a lot)

Iwannahurl

September1 wrote: »

It seems that research in Denmark shows that on some roads you can save lives by increasing speed limits, I couldn't find English article but google translate can help.
http://www.jv.dk/artikel/1678058:Indland--Raad--Hoejere-hastighed-gavner-trafiksikkerheden

Apparently certain motorways part and straight country roads benefit from that.

What's the evidence?

Here's one of Prof. Lahrmann's research projects, btw:

https://www.youtube.com/watch?v=11YZyV_lRys

CiniO

Speed limits on motorways are nonsense, and lead to dangerous situations.

Best example is driving through UK motorways, with moderate to high level of traffic.

Extremally low speed limit of 70MPH (112km/h) leads to most vehicles driving at very similar speed, because nearly everyone is doing speed limit. I personally don't like driving there.
You are in middle lane, and drivers on the right overtaking lane, are doing 1MPH faster than you. Overtaking takes ages. Sometimes someone starts overtaking you, and then in the middle of manouver slows down and keeps driving near you on other lane with the same speed, unabling you to change lane. Everyone is driving so steadily that it makes driving boring and people just don't concentrate. When I looked around barely anyone keeps proper driving position (with two hands on steering wheel). Lots of people do other things when driving, look at landscapes, etc...

Driving in Germany on unrestricted parts of autobahns is much better. Generally higher speeds cause better concentration. Overtaking takes only a short while as speed differences between vehicles are greater. Much nicer and IMO safer driving.

Here's a video when I was last in Germany. At the beginning of the video I'm doing about 140km/h but later accelerate to 217km/h (you can see first two digits on speedometer on the right bottom of the video).
All good and safe, and doesn't make driving on longer distance boring.

https://www.youtube.com/watch?v=ccIWvGGCbao

For some reason youtube processed video wrongly, and from 1:12 it repeats from beginning without sound. I don't know why.

Chimaera

IMO a large risk factor on high speed roads is speed differential with other traffic. It's one thing to be doing 160 km/h on a road where everyone is doing that speed or close to it. But if you're doing it on a road where the other traffic is only doing 100 km/h it's a problem.

Iwannahurl: we're all well aware of the correlation between speed and the magnitude of the impact. In a lot of cases, any direct impact above 80 km/h is going to be fatal. The discussion should be about not getting into impacts in the first place. (A car's crumple zone will allow about 0.4 m of deceleration. From 80 km/h (22.22 m/s) to 0 km/h in this distance imposes an average deceleration of 62.9 g. Some research suggests the average fatal deceleration for an adult is around 65 g.)

Better driver training is needed, especially around awareness and anticipation. Our vehicles' capabilities have vastly outstripped our skills as drivers but most of us haven't woken up to that fact. Many modern cars can easily do 160-180 km/h on a motorway, but few drivers have the skills to travel safely at those speeds. Until the driver education system makes some effort to incorporate motorway driving, this won't change.

Sobanek

Iwannahurl wrote: »

What's the evidence?

Here's one of Prof. Lahrmann's research projects, btw:

https://www.youtube.com/watch?v=11YZyV_lRys

If anyone supports this, they should be shot for supporting a fascist ideology.

paddyland

Chimaera wrote: »

IMO a large risk factor on high speed roads is speed differential with other traffic. It's one thing to be doing 160 km/h on a road where everyone is doing that speed or close to it. But if you're doing it on a road where the other traffic is only doing 100 km/h it's a problem.

...

Better driver training is needed, especially around awareness and anticipation. Our vehicles' capabilities have vastly outstripped our skills as drivers but most of us haven't woken up to that fact. Many modern cars can easily do 160-180 km/h on a motorway, but few drivers have the skills to travel safely at those speeds. Until the driver education system makes some effort to incorporate motorway driving, this won't change.

In fact, I firmly believe driving standards overall have got worse. Years ago, many people did not drive at all. Few homes had more than one car, and many had no car at all.

Among those who did drive, there were good drivers, and bad, as may be expected. But generally those who couldn't drive, didn't. Today, those who cannot drive, DO drive. Almost everyone drives, and as the overall number of drivers goes up, the mean average of good drivers goes down.

The proportion of good drivers on the road is terrible. I believe only a quarter of drivers or less have any good general idea of what they are doing, or are supposed to do. Half of all drivers I believe, based on over a million miles of driving and observation, are not properly aware of what they are doing, or should be doing. And somewhere approaching a quarter, are deliberately and belligerently driving badly, and know they are.

The good, safe, experienced and civilised drivers in this country, who have learnt well, and make an effort, are being held hostage by the greater majority who cannot drive, or care not about their own driving or anyone else's. Education is one thing, one very important thing, but how do you educate those who do not wish to be educated? You enforce the law. Learn, or get put off the road, end of.

It still comes down to, in my opinion, the fact that all drivers, good bad and atrocious, are too lucrative of revenue earners for the government, and we want them all out there driving, good, bad and indifferent. There is no will to educate them or police them. Don't rock the apple cart. Let the good, safe, experienced drivers slow down, put up and shut up.

It's rotten.

Sobanek

The best drivers I see on the road are usually HGV and bus drivers.
I've also noticed that a certain group of people is somehow a bit more focused on their driving then others (I know I'll get bashed for this but here it goes) - speeders.

paddyland

Sobanek wrote: »

The best drivers I see on the road are usually HGV and bus drivers.
I've also noticed that a certain group of people is somehow a bit more focused on their driving then others (I know I'll get bashed for this but here it goes) - speeders.

Absolutely.

thats not gone well

Sobanek wrote: »

The best drivers I see on the road are usually HGV and bus drivers.
I've also noticed that a certain group of people is somehow a bit more focused on their driving then others (I know I'll get bashed for this but here it goes) - speeders.

paddyland wrote: »

Absolutely.

IMO Certain messy logic here,

If you choose to speed, every single risk on that stretch of road grows exponentially.

In order to "manage" this increased risk you must concentrate more in case something does happen to account for the reduced reaction time and stopping distance available.

Sobanek

thats not gone well wrote: »

IMO Certain messy logic here,

If you choose to speed, every single risk on that stretch of road grows exponentially.

In order to "manage" this increased risk you must concentrate more in case something does happen to account for the reduced reaction time and stopping distance available.

Well, but then they are focused much more than the granny travelling in the middle lane at 80kph :rolleyes:

Stavros Murphy

Someone closely related to me went down the N7 from Dublin today, doing 120kph and was barely keeping up with the flow of traffic, 100 all the way on the signs.. the other day the same person, ahem, ermm, told me they were doing a sustained 180kph on the N7 and people were going past like he was doing 50.. so they were topping 200 anyway and it wasn't one or two either. The limits appear to be fluidly adhered to, erm, he told me. Personally, I wouldn't know though.

Mycroft H

Increase the speed limit? Need to be concentrating.

https://www.youtube.com/watch?v=AZHA4TfN2yU

Sobanek

Mycroft H wrote: »

Increase the speed limit? Need to be concentrating.

https://www.youtube.com/watch?v=AZHA4TfN2yU

This guy had plenty of time to react. He must've been distracted.

If I go 160kph (and sometimes I do) and it's usually an empty motorway, I still keep focused on two things: My rear view mirror and on what's happening in front of me.

Mycroft H

People don't concentrate. People speed. People daydream. That's always going to happen. Increase the speed limit and your just asking for these people to drive faster.

corktina

Mycroft H wrote: »

People don't concentrate. People speed. People daydream. That's always going to happen. Increase the speed limit and your just asking for these people to drive faster.

I agree.

I think what ius being mooted in the UK (to increse the limit in places and then rigidly enforce it) is the way to go

Iwannahurl

Sobanek wrote: »

This guy had plenty of time to react. He must've been distracted.

If I go 160kph (and sometimes I do) and it's usually an empty motorway, I still keep focused on two things: My rear view mirror and on what's happening in front of me.

Indeed. Far too much speedo watching in this country.

Sobanek

Iwannahurl wrote: »

Indeed. Far too much speedo watching in this country.

I don't see your point. I wasn't distracted and saw the yob. It's him who ran the stop sign.

September1

I think key point of this research is that low speed is not ultimate solution, what works in towns would not work in rural areas or for intercity travel. If Google Translate got it right it would suggest that people change behavior with speed limits, for example in 60kph zone half will be obeying speed limit and half would go 70kph - however once we move to perhaps 150kph zone then suddenly most of drivers would be going below speed limit.

In my opinion which I think would be really hated here speed limits should be used much more as informative signs and thus with great care - no thoughtless speed limits. If you go on long stretch of wide road that is limited to 80kph but can safely take higher speeds than drivers lose trust to signs, same with road construction warnings when there is no construction. This means when they encounter speed limits in places where it is necessary to slow down, they would be more likely to use own judgement.

Irishcrx

Have to agree with most above , the speed limits in most cases here in Ireland are very restrictive. Of course road safety is important but there is definatly a case to be had for the lack of concentration aspect. I regularly do the Dublin - Cork return route and have to stop at twice for coffee on the way to make sure I'm awake.

It's a long old stretch of road and after 10 minutes of plottering along at 120kph the mind starts to wander and you have to force yourself to keep your attention levels up as it feels far far too slow, a lot of sections of that road are very empty as well.

If I was to travel at 160kph , I guarantee concentration levels rise. I know a lot do that speed anyway and so do I in parts but am terrified of speed cameras!

ironclaw

Irishcrx wrote: »

If I was to travel at 160kph , I guarantee concentration levels rise. I know a lot do that speed anyway and so do I in parts but am terrified of speed cameras!

Really disagree with the 'higher speed' means more concentration point. Is there any scientific evidence to back that up? Plus higher, sustained concentration levels would be more fatiguing. So while you might be concentrating more, your going to get tired far more quickly. Le Mans would be a perfect example or any endurance race. And that is with training! Just my view on it.

Dublin to Cork is 255km. At 120km/h, thats 2 hours and 8 minutes. At 160km/h, its 96 minutes. So you've saved yourself, at absolute best, 32 minutes. And thats assuming you keep it planted at either of those speeds the entire way (Remembering again you won't have 255km of motorway). The idea of 'average' speed is really lost on most Irish drivers. Just count the number of people who repetitively pass out when on cruise control on Irish motorways, its astounding. Drop the hammer for a few lane hoggers or a bad overtake, and you'll quickly erode that average speed.

Ireland isn't like Europe or the States where you'll be doing 100's of km and it makes sense for a higher speed, the most your going to save is 30 mins. Is that worth the idiots we'll allow do these speeds? Not really if you ask me. I'd rather save on the hassle, traffic jams from the inevitable crashes and the insurance premium rises.

What I would be in favour for however is adaptive speed limits i.e. M50 at 120km/h between 10pm and 6am for example. And conversely, I'd be for a far lower limit during the peak traffic, as I believe half the problem is being hoon-ing it between junctions and then jamming on the brakes when they won't allow others merge. Also, a mandatory 2 car length gap for those in lane one. Or the likes of the N11 at night, flashing amber in favour of traffic on the N11 from town to Lochlinstown etc. Common place in Poland I believe.