> does this mean that the flow of traffic is constantly slowing down as it approaches intersections, even if the light is "green"?
Yes, if there's a sign before the intersection with a lower speed limit.
Say the road is a 90km/h road, there's an intersection and a 70km/h sign before it, you drive 70 through the intersection and 90 onwards (as it cancels the 70 sign).
It's there to prevent people from speeding through intersections and it is enforced in practice.
okay, but if the speed limit is 90, then how is that "speeding through the intersection" - you're supposed to be predictable when driving, hitting your brakes when approaching a "green" intersection is not predictable - for instance, i'd probably rear-end someone the first day. In the US we have some state laws like this, though, but not for traffic-controlled intersections. In california, for example they're called "blind" intersections, and regardless of the roadway's speed limit there is an arbitrary "customary and codified" speed limit through such blind intersections. It's been 15 years since i read the CA DMV handbook, but it's slow, <=25mph, even if the roadway approaching it is 35MPH.
But slowing down before an intersection with a green light, and not even every intersection? at least california had the decency to say "this circumstance, this speed" and no exceptions.
> okay, but if the speed limit is 90, then how is that "speeding through the intersection" - you're supposed to be predictable when driving, hitting your brakes when approaching a "green" intersection is not predictable - for instance, i'd probably rear-end someone the first day.
It's entirely predictable, you slow down when there's a lower speed limit sign. You are responsible for being alert when driving, if a 20km/h lower speed limit makes you rear end someone, you just weren't alert enough.
The sign is far enough from the actual intersection that you have the time to slow down without braking at all. In practice, the limits are usually done in a way that reduces accelerating/braking between consequent intersections and so on.
> But slowing down before an intersection with a green light, and not even every intersection? at least california had the decency to say "this circumstance, this speed" and no exceptions.
Sorry, but I don’t understand what's inconsistent here. You slow down if there's a sign, otherwise you keep going the same speed.
Again, this rule is in place to (1) keep people from speeding through intersections (speeding to catch green lights) and (2) to keep the speed limit low enough so that one can completely stop in case a pedestrian/cyclist mistakenly attempts to cross, someone cuts them over etc.
It seems to be working, looking at the data comparing my Central European country's traffic deaths to the US [1].
> Intersections here cancel the speed limit signs that are before them
does this mean that the flow of traffic is constantly slowing down as it approaches intersections, even if the light is "green"?