Talk:Proposed features/Emergency Traffic Signals

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It is stated "we need" this new tag but this is not adequately reasoned discussed or argued.

What is the time penalty applied by a router to a set of traffic lights? How much time should the penalty be when the fire truck operates them and pulls out? How often does the fire truck use them?

Perhaps the time penalty should just be ignored - letting the fire truck out would take just as much a time penalty as ordinary lights and happens at irregular intervals.

Now do we still need a new tag?

- preceding comment by Drlizau.

Well Drlizau (Please tag your comments on talk pages...), I'm not 100% sure of what the "exact" penalty is that each router applies to traffic light nodes, but I do know they have one. While doing some Googling, I came across this page where somebody made a OSMImporter program. If you look down on that page, you can see this line: "# A traffic light penalty can be applied to all edges adjacent to traffic lights". Means that the penalty can be almost anything. That's where this new traffic_signals=emergency tag comes it. If the routing software people accept it, it will override any time penalty assigned to the lights and eliminate it for traffic. To be honest, I've never seen any of my local fire stations have to activate their lights, or any others that I've encountered in other states. I have see ones at tunnels occasionally activated, but that's extremely rare as well (well, unless an idiot truck driver drives his over-height truck into one of our tunnels here in Pittsburgh and gets it stuck in there, but I digress....).
Now, I do admit saying that we "need" that tag was a little over the top, but wouldn't it be the OSM way to let people know which traffic lights are "real" and which ones are "emergency only"? That is what this proposal is all about, making a standard tag for these such traffic lights. This is just like the service=parking_aisle tag that helps define what type of highway=service it is. -- rickmastfan67 09:49, 13 January 2011 (UTC)


I've already been using highway=traffic_signals traffic_signals=emergency (as well as traffic_signals=blinker for a single-ball blinker and traffic_signals=blink_mode for a standard signal that's in permanent blink mode), so I agree with that part. No comment on emergency=*, and I oppose treating bridge/tunnel signals the same as those in front of fire stations. As for rationale, I don't care much about routing, but it's nice to know if the residential street you're planning on turning left onto the main highway from has a real signal or just a blinker. --NE2 16:07, 13 January 2011 (UTC)

Well NE2, what would you suggest for the tunnel ones? They do act like the emergency signals @ fire stations. I get what you say about the bridge ones. Those could be something like "traffic_signals=lift_bridge". -- rickmastfan67 00:46, 14 January 2011 (UTC)


In France we have traffic lights on single streets (ie. not a junctions) that are activated by pedestrians for crossing. Unless there is someone to press the button they are inactive (blinking orange). Routing-wise, this gives you roughly the same probability of a red light than an emergency traffic signal. Could we perhaps merge these two cases as one tag ? Firstvariation 12:06, 20 January 2011 (UTC)

In Germany it's the same. There are traffic lights that are turned off 99% of the time (have seen it in use one time in the last year). Such lights could be rendered as white lights as proposed and emergency lights as suggested by Lulu-Ann with a strobe beacon(see "Rendering").--LetzFetz 22:35, 31 May 2011 (BST)

On the same node as standard traffic signals

Hi, I think that Emergency Traffic Signals are 99% on the same pole and node like the ordinary ones, so let's better use traffic_signals:emergency=yes, like with traffic_signals:sound=*, traffic_signals:vibration=*, traffic_signals:arrow=* etc. Lulu-Ann

Rendering

I would like to have an ordinarily colored traffic signals icon with a representation of a rotating yellow light on top (of course not rotating!). Lulu-Ann