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Comment by wafflemaker | Hacker News Reader

30 km\h limit in densely populated and heavily used by pedestrians first\last 2-5 minutes of your travel does what? Extends your travel time by 1 minute? At the same time making it nearly impossible to kill a kid, cat, dog or human in these places.

Same goes with the right of way in these places. You're in a car, you're getting where you're going much faster anyway, so you let pedestrians go first. On pedestrian crossings, and often even without them in such "last leg" places.

It's completely logical. You don't go faster in places where somebody can suddenly walk out from behind a parked car, bush, whatever. But it's a cultural thing in Scandinavia.

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You, just like the grandparent, confuse egregious 0% tolerance speed enforcement with speed limits. Speed limits dictates stopping distance and is a key factor in collision avoidance. No one is asking to abolish speed limits.

The problem is when passenger cars that require a fraction of stopping distance of a truck at given speed limit are fined for going 3-4 km over limit. Essentially, fined for driving at a speed where they can stop many meters before a truck going the sign posted limit. Revenue raising in the name of safety, down playing other factors like attention, driver training, road design, maintenance, and so on, but they don't bring as much money.

I don't see anything in the parent comments referencing or advocating for 0% tolerance speed enforcement. In the UK speed limits are typically enforced with a 10% grace factor.

Instead, there's a push to reduce limits ever closer to zero.

30mph was close to the sweet spot and had been for decades. Or it would have been with a reasonable level of enforcement.

But as the ideological and/or climate-driven war on cars ramped up there's been a big push to reduce ever-more areas to 20mph, which is just too slow, especially when deployed widely/indiscriminately as it has been in Wales. (Used very sparingly, e.g. outside schools, 20mph limits were a good 'take particular care' signal to motorists - but that effect is lost when they're widespread)

Is it really about safety or is it about 'fuck cars'?

If you look at outcomes, 50km/h (30mph) is much less safe than 30km/h (20mph). If you look at the physics, that’s not surprising - stopping distances increase super linear. At the point where a 30km/h car would have come to a stop, a 50km/h car still impacts with 30km/h.

On the other hand, average speeds in populated areas usually are way lower than 30km/h, so lowering the top speed to 30km has negligible effect on travel times.

If you consider 50km/h the sweet spot, you prioritize vehicle speed over the very real risk of bodily harm for all other traffic participants.

> At the point where a 30km/h car would have come to a stop, a 50km/h car still impacts with 30km/h.

At that point it's barely superlinear. That means instead of dropping by 30kph it dropped 20kph.

Personally I'd focus more on how even a linear increase in stopping distance is a problem when pedestrians are around.

> On the other hand, average speeds in populated areas usually are way lower than 30km/h, so lowering the top speed to 30km has negligible effect on travel times.

Negligible speed impact also means negligible safety impact.

> 30mph was close to the sweet spot and had been for decades.

For car drivers maybe. From the POV of a pedestrian, 30 mph is very fast.

So, assuming you do support some enforcement for passenger cars, at what speed would a ticket be warranted? Because this is exactly the dumb setup they have in California for example.

Speed limit is 65, everyone is doing 80. When you pull over someone how do you explain why only that person gets a ticket?

A limit is only a limit when it's enforced. Anything else will become arbitrary.

> cars that require a fraction of stopping distance of a truck at given speed

You may want to update your knowledge on the stopping distances of modern trucks.

> are fined for going 3-4 km over limit

Obviously. Is there anything confusing about the word "limit" in particular that you don't understand?

> Essentially, fined for driving at a speed where they can stop many meters before a truck going the sign posted limit.

It is not your job as a driver to decide whether to stick to a particular traffic rule or not. The limit is there, so follow it.

You go 30 km/h. A kid runs on the street. You manage to stop just in front of it.

You go 40 km/h. The same kid runs on the same street. You brake the exact same way. You hit the kid with over 30 km/h. You just killed a kid.

Kids don't run out into the street chasing stray footballs anymore. They're all indoors staring at screens.

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