The Straight Dope

Go Back   Straight Dope Message Board > Main > General Questions

Reply
 
Thread Tools Display Modes
  #1  
Old 02-17-2013, 02:26 PM
jebert jebert is offline
Guest
 
Join Date: May 1999
Floridians: What's that blue light on traffic signals?

I recently traveled to Florida - Ft. Myers area specifically. I noticed several intersections where there was a small blue light at the bottom of one of the traffic signals hanging over the intersection. I also noticed that the blue light turned off when the signal changed to green.

Can any of you Floridians explain what this blue light is for?
Reply With Quote
Advertisements  
  #2  
Old 02-17-2013, 02:49 PM
Digital is the new Analog Digital is the new Analog is online now
Apple Advisory Board
 
Join Date: Oct 2010
Location: Mount Crumpit
Posts: 3,941
Quote:
Originally Posted by jebert View Post
I recently traveled to Florida - Ft. Myers area specifically. I noticed several intersections where there was a small blue light at the bottom of one of the traffic signals hanging over the intersection. I also noticed that the blue light turned off when the signal changed to green.

Can any of you Floridians explain what this blue light is for?
I'm on the other coast of Florida, and apparently we do things differently here.
I've don't believe I've every seen a blue light on a traffic signal like that. Sorry.

That being said - this forum claims they are "rat" lights. They apparently are used to indicate when the light is red, to aid police.
Reply With Quote
  #3  
Old 02-17-2013, 03:37 PM
Hail Ants Hail Ants is offline
Charter Member
 
Join Date: Jan 2000
Location: NY USA
Posts: 5,384
When will people learn that Google long ago became the all-knowing Matrix?!

Just put in 'blue light on traffic signals', and got this!
Reply With Quote
  #4  
Old 02-17-2013, 04:31 PM
pkbites pkbites is offline
Charter Member
 
Join Date: Apr 2000
Location: Majikal Land O' Cheeze!
Posts: 8,044
Quote:
Originally Posted by Digital is the new Analog View Post
They apparently are used to indicate when the light is red, to aid police.
Which is fine, but maybe people wouldn't run lights so much in Florida if they didn't stay red so gawddam long! I timed one in Sarasota at 4 minutes 30 seconds! WTF?
Reply With Quote
  #5  
Old 02-17-2013, 04:44 PM
Digital is the new Analog Digital is the new Analog is online now
Apple Advisory Board
 
Join Date: Oct 2010
Location: Mount Crumpit
Posts: 3,941
Quote:
Originally Posted by pkbites View Post
Which is fine, but maybe people wouldn't run lights so much in Florida if they didn't stay red so gawddam long! I timed one in Sarasota at 4 minutes 30 seconds! WTF?
Na. Floridians will still run them.
Sometimes it seems we deliberately don't synchronize our lights just so there are more red lights to run.
Reply With Quote
  #6  
Old 02-17-2013, 10:53 PM
Bob X Bob X is offline
Guest
 
Join Date: Feb 2013
The blue light means that the blue-hairs can go.
Reply With Quote
  #7  
Old 02-18-2013, 02:22 AM
Senegoid Senegoid is offline
Member
 
Join Date: Sep 2011
Location: Sunny California
Posts: 7,578
I have seen little blue lights something like this in Simi Valley (southern Calif.), several years ago. They aren't below or above the signal, but on the back side of them. I guessed then that they were to help cops tell, even seeing a signal from behind, when they are red.

Calif. is also the land of the metered freeway on-ramps. Most of these also have a light facing the back side, so a cop can park ahead a ways, and see when the light is red.

Last edited by Senegoid; 02-18-2013 at 02:22 AM..
Reply With Quote
  #8  
Old 02-18-2013, 03:12 AM
Dr. Strangelove Dr. Strangelove is online now
Guest
 
Join Date: Dec 2010
Quote:
Originally Posted by Senegoid View Post
I have seen little blue lights something like this in Simi Valley (southern Calif.), several years ago. They aren't below or above the signal, but on the back side of them. I guessed then that they were to help cops tell, even seeing a signal from behind, when they are red..
They're here in Northern California as well. It seems they're more common on the lights mounted lower on the side of the road (as compared to ones on the overhead pole).
Reply With Quote
  #9  
Old 02-18-2013, 03:13 AM
Johanna Johanna is online now
Charter Member
 
Join Date: Oct 1999
Location: Altered States of America
Posts: 11,525
Call me crazy, but to my thinking the best way to tell a red light is on is that you can see a red light. I don't get how sticking a blue light under it makes any difference at all.
Reply With Quote
  #10  
Old 02-18-2013, 03:46 AM
Alley Dweller Alley Dweller is offline
Guest
 
Join Date: Feb 2011
Quote:
Originally Posted by Johanna View Post
Call me crazy, but to my thinking the best way to tell a red light is on is that you can see a red light. I don't get how sticking a blue light under it makes any difference at all.
Certainly if you are facing the same direction as the light.

But sometimes traffic going one way has a longer red/green than traffic going the other way. If you are facing the other way, you would not be able to see whether oncoming traffic has a red or green.

And if you are approaching the intersection from the cross-street, you may not be able to see the traffic light for the traffic traveling perpendicular to your street at all.
Reply With Quote
  #11  
Old 02-18-2013, 07:02 AM
chappachula chappachula is offline
Guest
 
Join Date: May 2002
Quote:
Originally Posted by Alley Dweller View Post
If you are facing the other way, you would not be able to see whether oncoming traffic has a red or green.

And if you are approaching the intersection from the cross-street, you may not be able to see the traffic light for the traffic traveling perpendicular to your street at all.
So are these blue lights intended only for the police? Or are they useful to all drivers?


And--a related question:
If they are intended only to help the cops---why not use cameras, instead of little blue lights?
Cameras are dirt cheap these days. You could probably mount a camera on every single traffic light, including an auto-focusing device and a wi-fi hookup, for about the price of 3 or 4 traffic fines. Thereafter....it's free money for the city.
Is Big Brother on the way?and if not, why not?
Reply With Quote
  #12  
Old 02-18-2013, 07:07 AM
Monty Monty is offline
Straight Dope Science Advisory Board
 
Join Date: Feb 1999
Location: Beijing, China
Posts: 17,801
Call me silly, but I'd think a camera would have the light-jumber end up with a ticket later on. Now, if a cop sees the jumper jump a light, then he'll get a ticket (or at least a warning) and perhaps not jump more red lights that day.
Reply With Quote
  #13  
Old 02-18-2013, 07:13 AM
MilTan MilTan is offline
Charter Member
 
Join Date: Apr 2000
Location: Austin, but NC at heart
Posts: 1,437
Quote:
Originally Posted by Monty View Post
Call me silly, but I'd think a camera would have the light-jumber end up with a ticket later on. Now, if a cop sees the jumper jump a light, then he'll get a ticket (or at least a warning) and perhaps not jump more red lights that day.
Also, the revenue proposition is a little different for cops' catching light-runners (where the revenue goes straight to the department) than for traffic cameras' doing the same (where the bulk of the revenue goes to the camera operator, not the department).
Reply With Quote
  #14  
Old 02-18-2013, 07:41 AM
chappachula chappachula is offline
Guest
 
Join Date: May 2002
Quote:
Originally Posted by MilTan View Post
Also, the revenue proposition is a little different for cops' catching light-runners (where the revenue goes straight to the department) than for traffic cameras' doing the same (where the bulk of the revenue goes to the camera operator, not the department).
You're saying that there really is a good source of revenue here. So why doesn't the city open a "camera operator" department? (just like they have a department of building inspectors, and health inspectors).
Are there technical problems make it unfeasible?

Not that I want to have cameras everywhere....but if there's a way to take money from people, eventually somebody's gonna do it...either private or government. Why hasn't it happened yet?

Last edited by chappachula; 02-18-2013 at 07:42 AM..
Reply With Quote
  #15  
Old 02-18-2013, 07:48 AM
crucible crucible is offline
Guest
 
Join Date: Jun 2011
so, no one really knows what the blue lights are for.

Quote

What are the tiny blue lights on the backside of the stoplights?-Steve Clelland

Stoplights are a simple concept - green means go, yellow means slow down and red means stop. But blue? Blue could result in a ticket and a fine.

Remaining text removed by moderator. You may read it on the original site (KTVB News) here.

Last edited by Gary "Wombat" Robson; 02-18-2013 at 01:56 PM.. Reason: Copyrighted material removed by moderator
Reply With Quote
  #16  
Old 02-18-2013, 07:54 AM
crucible crucible is offline
Guest
 
Join Date: Jun 2011
I have seen screwed up lights in Florida, esp. where the size of the road is large, multi-lanes, and they split out the left turn lane or lanes such that they are not right next to the lanes continuing straight ahead....then they give the left turn lanes a green light instead of a green arrow. The green light does not mean you have the right of way, but a driver might not understand that and could pull directly into oncoming traffic. hard to explain until you are there and confused whether you should go, or not.
Reply With Quote
  #17  
Old 02-18-2013, 08:56 AM
Simplicio Simplicio is offline
Guest
 
Join Date: Dec 2003
Quote:
Originally Posted by Monty View Post
Call me silly, but I'd think a camera would have the light-jumber end up with a ticket later on. Now, if a cop sees the jumper jump a light, then he'll get a ticket (or at least a warning) and perhaps not jump more red lights that day.
People running red lights are also probably disproportionally likely to be committing other crimes as well (driving without a license or with a suspended license, driving drunk, driving at night with a graduated license, fleeing another crime, etc.).

I live in a college town, and I notice the cops station a car near the intersection leading away from the bars around closing time, I presume to snap up all the plastered students who fly through the red light.
Reply With Quote
  #18  
Old 02-18-2013, 09:02 AM
April R April R is offline
Guest
 
Join Date: Sep 2012
In Memphis the Blue Light means there is a traffic cam at that particular intersection and if you run the light you will get a nifty invite form the local police department.
Reply With Quote
  #19  
Old 02-18-2013, 09:17 AM
Hypno-Toad Hypno-Toad is offline
Guest
 
Join Date: Sep 2004
One reason for the blue lights instead of traffic cams is that a lot of residents fight the installation of traffic cams as being problematic and prone to error. The local paper that I read this in is, in fact, the Fort Myers News Press, the location mentioned in the OP. The blue light synced with the red light gets around the reliability issue because it's just a visual cue to help police officers. Therefore, it becomes a matter of the cops witnessing the crime personally, which already has plenty of precendent.

Jebert, you should have told me you were coming. I'd have bought a cake.
__________________
This is my signature. There are many like it, but this one is mine.

Last edited by Hypno-Toad; 02-18-2013 at 09:18 AM..
Reply With Quote
  #20  
Old 02-18-2013, 10:15 AM
Lanzy Lanzy is offline
Charter Member
 
Join Date: Apr 2004
Location: Orlando
Posts: 3,624
Quote:
Originally Posted by pkbites View Post
Which is fine, but maybe people wouldn't run lights so much in Florida if they didn't stay red so gawddam long! I timed one in Sarasota at 4 minutes 30 seconds! WTF?
I am absolutely convinced there are people in Florida that will not stop at ANY red light unless there is a car already stopped in front of them. Annd once I got the finger as a guy zipped around me to run one I had just stopped at.
Reply With Quote
  #21  
Old 02-18-2013, 10:54 AM
DavidPeab DavidPeab is offline
Guest
 
Join Date: Nov 2012
I'm not a Floridian, but I wonder if it has something to do with a sensor that detects a signal from oncoming emergency vehicles and changes the light from red to green so they can safely pass through the intersection.
Reply With Quote
  #22  
Old 02-18-2013, 12:22 PM
Hypno-Toad Hypno-Toad is offline
Guest
 
Join Date: Sep 2004
No. I've seen ambulances down here have to (carefully) negotiate red lights. Usually, not a problem unless all the lanes at the red light have cars in them.
__________________
This is my signature. There are many like it, but this one is mine.
Reply With Quote
  #23  
Old 02-18-2013, 01:55 PM
Gary "Wombat" Robson Gary "Wombat" Robson is offline
Vombatus Moderatus
Moderator
 
Join Date: Mar 2003
Location: Montana, U.S.A.
Posts: 9,444
Mod note: crucible

Quote:
Originally Posted by crucible View Post
so, no one really knows what the blue lights are for.

Quote

What are the tiny blue lights on the backside of the stoplights?-Steve Clelland....
[moderator note]
Crucible, don't cut and paste copyrighted text from other sites onto our board. If you wish to post a small excerpt, that's fine, but only if you link to the original source. I have removed what you pasted and replaced it with a link to the original material.

No warning issued.
[/moderator note]
__________________
Everything in moderation!
Reply With Quote
  #24  
Old 02-18-2013, 02:52 PM
Gary T Gary T is offline
Member
 
Join Date: Mar 2002
Location: KCMO
Posts: 9,524
Quote:
Originally Posted by chappachula View Post
You're saying that there really is a good source of revenue here. So why doesn't the city open a "camera operator" department? (just like they have a department of building inspectors, and health inspectors).
Are there technical problems make it unfeasible?
It's not just a matter of "operating" a camera, the way one might operate, say, a radar gun. It's its own industry, covering manufacture, testing, procurement, installation, and monitoring of the cameras. It's a bigger business endeavor than most cities want to get into, especially when they can lease the set-up and rake in their share of the dough with essentially no investment and no maintenance/operation headaches.
Reply With Quote
  #25  
Old 02-18-2013, 05:44 PM
AdamF AdamF is offline
Guest
 
Join Date: Jul 2012
I am not sure if this is relevant.

In Calgary Canada, small blue light next to the regular traffic lights indicates that the automatic signal cycle has been over-ridden. Police, EMTs and buses can signal the traffic lights from about 1000 feet away, and they will get a green light when they arrive to the intersection.
Reply With Quote
  #26  
Old 02-18-2013, 05:53 PM
JRDelirious JRDelirious is online now
Charter Member
 
Join Date: Aug 1999
Location: San Juan, PR
Posts: 10,393
[aside]

Quote:
Originally Posted by Senegoid View Post
Calif. is also the land of the metered freeway on-ramps. Most of these also have a light facing the back side, so a cop can park ahead a ways, and see when the light is red.
First time I ever drove in Cali (first time I ran into them, years ago) these got me scared good for the first few days. "Wait, does it have a light now? Does it always?"

[/aside]

Last edited by JRDelirious; 02-18-2013 at 05:55 PM..
Reply With Quote
  #27  
Old 02-20-2013, 07:17 AM
Bullitt Bullitt is offline
Member
 
Join Date: Apr 2012
Location: San Francisco, CA, USA
Posts: 11,916
Quote:
Originally Posted by Dr. Strangelove View Post
They're here in Northern California as well. It seems they're more common on the lights mounted lower on the side of the road (as compared to ones on the overhead pole).
Where? I live on the peninsula and haven't noticed them. I was up in The City on Sunday and didn't notice any. Of course, I wasn't looking or aware of this, and I'll pay attention for them now.
Reply With Quote
  #28  
Old 02-20-2013, 08:57 AM
Spiff Spiff is offline
Charter Member
 
Join Date: May 2000
Location: In the SPIFF Bunker
Posts: 2,598
Floridians: What's that blue light on traffic signals?

They light up at 4 p.m. to signal that the blue plate specials are now being served at Perkins.
Reply With Quote
  #29  
Old 02-20-2013, 01:31 PM
Dr. Strangelove Dr. Strangelove is online now
Guest
 
Join Date: Dec 2010
Quote:
Originally Posted by echo7tango View Post
Where? I live on the peninsula and haven't noticed them. I was up in The City on Sunday and didn't notice any. Of course, I wasn't looking or aware of this, and I'll pay attention for them now.
There are at least a few in downtown San Jose, though I don't remember precisely where. And I know for a fact that there is one on this signal in Sunnyvale.
Reply With Quote
  #30  
Old 02-20-2013, 09:27 PM
kittenblue kittenblue is offline
Charter Member
 
Join Date: Apr 2000
Location: Cleveland, Ohio
Posts: 6,476
Here in Ohio the blue lights are emergency-vehicle indicators that start flashing when an ambulance of fire truck approaches and the lights themselves lock on red. However...they don't seem to start up until the emergency crews are practically underneath the lights, so they don't really give enough warning time.
Reply With Quote
  #31  
Old 02-20-2013, 09:33 PM
Bullitt Bullitt is offline
Member
 
Join Date: Apr 2012
Location: San Francisco, CA, USA
Posts: 11,916
Quote:
Originally Posted by Dr. Strangelove View Post
There are at least a few in downtown San Jose, though I don't remember precisely where. And I know for a fact that there is one on this signal in Sunnyvale.
I pass near that one in Sunnyvale. I'll check it out. Thanks.
Reply With Quote
  #32  
Old 02-20-2013, 10:38 PM
Bambi Hassenpfeffer Bambi Hassenpfeffer is offline
Guest
 
Join Date: Dec 2000
Quote:
Originally Posted by chappachula View Post
So are these blue lights intended only for the police? Or are they useful to all drivers?
The way the newspapers explained it when they were first rolling out years ago is that the police at an intersection CANNOT write a citation for running a red light if they cannot directly tell that the light is red. Every major intersection around here (Pinellas County, FL) has them (except ours are white), and they illuminate when the light they're attached to is red.

This is from the Orlando Sentinel explaining them in more detail.

Quote:
Originally Posted by crucible
so, no one really knows what the blue lights are for.
The first two responses in this thread said basically the same thing I just did. But I'll call this out here so you see it directly this time.
Reply With Quote
  #33  
Old 03-03-2013, 03:12 PM
Bullitt Bullitt is offline
Member
 
Join Date: Apr 2012
Location: San Francisco, CA, USA
Posts: 11,916
Quote:
Originally Posted by Dr. Strangelove View Post
There are at least a few in downtown San Jose, though I don't remember precisely where. And I know for a fact that there is one on this signal in Sunnyvale.

Quote:
Originally Posted by echo7tango View Post
I pass near that one in Sunnyvale. I'll check it out. Thanks.

I just drove by that intersection in Sunnyvale and I didn't see any blue light there. There's a lot of construction there, so things might be changing, but the lights looked like they haven't been touched by the construction and are still pretty new. This is an area with new and ongoing construction.
Reply With Quote
  #34  
Old 03-04-2013, 09:07 AM
furryman furryman is offline
Charter Member
 
Join Date: Feb 2001
Location: Collinwood, Collinsport
Posts: 2,361
The blue light goes on when there's a sale at K-Mart.
Reply With Quote
  #35  
Old 03-04-2013, 09:11 AM
Bullitt Bullitt is offline
Member
 
Join Date: Apr 2012
Location: San Francisco, CA, USA
Posts: 11,916
There's no K-Mart there, but there's a (relatively) new Target. Maybe they removed the blue light altogether.
Reply With Quote
  #36  
Old 06-20-2013, 11:41 PM
Dr. Strangelove Dr. Strangelove is online now
Guest
 
Join Date: Dec 2010
Quote:
Originally Posted by echo7tango View Post
I just drove by that intersection in Sunnyvale and I didn't see any blue light there. There's a lot of construction there, so things might be changing, but the lights looked like they haven't been touched by the construction and are still pretty new. This is an area with new and ongoing construction.
I finally had a chance to walk by the light again and snap a picture. See here (the blue light is about 1/3 from the left and 1/2 way down). There's another similar light above it (also on the backside of the signal) that glows red--I think when the cross street has a green light. Didn't spend enough time observing it to really figure out the pattern, though.
Reply With Quote
  #37  
Old 06-21-2013, 12:00 AM
Bullitt Bullitt is offline
Member
 
Join Date: Apr 2012
Location: San Francisco, CA, USA
Posts: 11,916
Cool, Dr. S, I'll go check it out. Thanks.
Reply With Quote
  #38  
Old 06-21-2013, 03:35 AM
SpyOne SpyOne is offline
Guest
 
Join Date: Mar 2010
Quote:
Originally Posted by pkbites View Post
Which is fine, but maybe people wouldn't run lights so much in Florida if they didn't stay red so gawddam long! I timed one in Sarasota at 4 minutes 30 seconds! WTF?
In Connecticut the law said that if a light had been red for 2 minutes, you could assume it was broken and proceed accordingly.
Reply With Quote
  #39  
Old 06-21-2013, 03:45 AM
SpyOne SpyOne is offline
Guest
 
Join Date: Mar 2010
Quote:
Originally Posted by chappachula View Post
So are these blue lights intended only for the police? Or are they useful to all drivers?


And--a related question:
If they are intended only to help the cops---why not use cameras, instead of little blue lights?
Imagine you are in a police car racing as fast as you can to the site of a shooting. You are approaching an intersection (with your lights and siren on), and the light is red in your direction. You need to slow down and proceed carefully, because traffic on the other streets may not have heard your siren yet.
Is their light green? Is it red yet, and your is preparing to turn green?
The answer to those questions could make a big difference, just as the few seconds you might save could make a big difference.

Years ago, the community I lived in started a bus service, and the buses had a cool feature: right next to the central brake light were two other lights, one green one yellow. It rapidly became obvious what the lights meant: green meant the driver was pressing the gas pedal, yellow meant neither gas nor brake.
I often wonder why I haven't seen that on more vehicles since.
Reply With Quote
  #40  
Old 06-21-2013, 03:47 AM
SpyOne SpyOne is offline
Guest
 
Join Date: Mar 2010
Quote:
Originally Posted by crucible View Post
I have seen screwed up lights in Florida, esp. where the size of the road is large, multi-lanes, and they split out the left turn lane or lanes such that they are not right next to the lanes continuing straight ahead....then they give the left turn lanes a green light instead of a green arrow. The green light does not mean you have the right of way, but a driver might not understand that and could pull directly into oncoming traffic. hard to explain until you are there and confused whether you should go, or not.
Locally, they just replaced solid green for left turn lanes with a blinking yellow arrow, which is IMO clearer about what it means.
Reply With Quote
Reply



Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 03:10 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Send questions for Cecil Adams to: cecil@chicagoreader.com

Send comments about this website to: webmaster@straightdope.com

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Publishers - interested in subscribing to the Straight Dope?
Write to: sdsubscriptions@chicagoreader.com.

Copyright 2013 Sun-Times Media, LLC.