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Blue lights over traffic signals

Started by codyg1985, July 09, 2011, 04:02:44 AM

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codyg1985

I noticed that in the Daytona and DeLand areas there were blue lights over the traffic signals that would activate when the signal turns red. Is this some sort of safety feature? Is this in the MUTCD?
Cody Goodman
Huntsville, AL, United States


xcellntbuy


Alex

They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

US71

Quote from: Alex on July 09, 2011, 08:49:17 AM
They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

I don't have a photo, but I've noticed some signals have a "Halo Effect" with the white lights. It encircles the red and blinks on and off, creating a halo around the red.
Like Alice I Try To Believe Three Impossible Things Before Breakfast

NE2

It's a 'blue light special'. When the blue light is on you're allowed to run the red.
pre-1945 Florida route log

I accept and respect your identity as long as it's not dumb shit like "identifying as a vaccinated attack helicopter".

US71

Quote from: NE2 on July 09, 2011, 09:29:22 AM
It's a 'blue light special'. When the blue light is on you're allowed to run the red.

After you. :|
Like Alice I Try To Believe Three Impossible Things Before Breakfast

SSF

Quote from: US71 on July 09, 2011, 08:55:48 AM
Quote from: Alex on July 09, 2011, 08:49:17 AM
They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

I don't have a photo, but I've noticed some signals have a "Halo Effect" with the white lights. It encircles the red and blinks on and off, creating a halo around the red.

Alabama uses the halo white lights on their four lanes. 

realjd

Like others said, they're rat lights. Cops use them for red light enforcement. We have white ones here in Palm Bay (on the rare occasion they arent burned out). Like blue reflectors for fire hydrants, I don't think they're regulated by the MUTCD.

Brandon

Quote from: Alex on July 09, 2011, 08:49:17 AM
They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

We use similar lights around here.  However, they flash for the "green" street, and are solid for the "red" street when triggered by a police car, fire truck, or ambulance.
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton

"Symbolic of his struggle against reality." - Reg

realjd

Quote from: Brandon on July 10, 2011, 07:52:24 AM
Quote from: Alex on July 09, 2011, 08:49:17 AM
They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

We use similar lights around here.  However, they flash for the "green" street, and are solid for the "red" street when triggered by a police car, fire truck, or ambulance.

Those are for the emergency vehicle preemption system. The lights we're talking about down here are for red light enforcement - "rat lights". They're on when the light is red, off when green. It's so a cop on any side of the intersection can catch red light runners without needing to see the front of the signal.

Brandon

Quote from: realjd on July 11, 2011, 08:13:14 AM
Quote from: Brandon on July 10, 2011, 07:52:24 AM
Quote from: Alex on July 09, 2011, 08:49:17 AM
They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

We use similar lights around here.  However, they flash for the "green" street, and are solid for the "red" street when triggered by a police car, fire truck, or ambulance.

Those are for the emergency vehicle preemption system. The lights we're talking about down here are for red light enforcement - "rat lights". They're on when the light is red, off when green. It's so a cop on any side of the intersection can catch red light runners without needing to see the front of the signal.

Wouldn't the simple fact that the cross street has a green signal be enough?
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton

"Symbolic of his struggle against reality." - Reg

froggie


realjd

Quote from: Brandon on July 12, 2011, 07:08:43 AM
Quote from: realjd on July 11, 2011, 08:13:14 AM
Quote from: Brandon on July 10, 2011, 07:52:24 AM
Quote from: Alex on July 09, 2011, 08:49:17 AM
They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

We use similar lights around here.  However, they flash for the "green" street, and are solid for the "red" street when triggered by a police car, fire truck, or ambulance.

Those are for the emergency vehicle preemption system. The lights we're talking about down here are for red light enforcement - "rat lights". They're on when the light is red, off when green. It's so a cop on any side of the intersection can catch red light runners without needing to see the front of the signal.

Wouldn't the simple fact that the cross street has a green signal be enough?

It depends on the phasing of the turn lanes, the red clearance phase, etc. Most red light runners around here aren't he blow-through-the-light-when-its-been-red-for-several-minutes types, they're the sneak-through-as-the-light-changes types.

I've never payed that much attention to the blue ones in the Orlando/Kissimmee area, but here they put them on the turn arrows also.

Brandon

Quote from: froggie on July 12, 2011, 07:14:08 AM
Not with the "all red" phase.


That only lasts a second.  Still too easy to tell, IMHO w/o any silly lights.
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton

"Symbolic of his struggle against reality." - Reg

UptownRoadGeek

Quote from: Brandon on July 12, 2011, 07:08:43 AM
Wouldn't the simple fact that the cross street has a green signal be enough?

That's pretty much how it is in my city. If the cross street is green you have red unless it's a pedestrian signal that sends the entire intersection red. Either way you can clearly see what color the cross street has, at least in this area anyway.

roadman65

They have them on the Osceola Parkway at John Young Parkway in Kissimmee, FL.  The problem is the intersection now is a SPUI and has its signal heads mounted to the overpass.  The blue lights cannot be seen in all fours for the straight through signals on the Osceola Parkway because the signals are on the outside of the bridge girders.  Here it is not much of a rat light and wonder why even to install them at all at this location.
Every day is a winding road, you just got to get used to it.

Sheryl Crowe

FLRoadsGuy

We have had them here in the Ft Myers Cape Coral area for the past 8 years now. I call them Tattle-tale lights. The first versions were very hard to see in the daylight hours with the bulb not so bright and the the cover being a dark blue color. (FYI this is my first post on this forum.)

thenetwork

Out here in Grand Junction, CO, we use the blue "rat lights" as well.  Some are mounted on the sides of the overhead traffic lights, and one is mounted on the nack of a pedestrian crosswalk assembly.  The latter is used at an intersection which prohibits right turns on red, so if anyone makes the turn when the blue light is on, the cops turn on the other blue light!!!

BTW, it is just coincidence that the latter is located at the intersection where a K-Mart sits nearby.

vtk

#18
Quote from: Brandon on July 12, 2011, 07:08:43 AM
Quote from: realjd on July 11, 2011, 08:13:14 AM
Quote from: Brandon on July 10, 2011, 07:52:24 AM
Quote from: Alex on July 09, 2011, 08:49:17 AM
They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

We use similar lights around here.  However, they flash for the "green" street, and are solid for the "red" street when triggered by a police car, fire truck, or ambulance.

Those are for the emergency vehicle preemption system. The lights we're talking about down here are for red light enforcement - "rat lights". They're on when the light is red, off when green. It's so a cop on any side of the intersection can catch red light runners without needing to see the front of the signal.

Wouldn't the simple fact that the cross street has a green signal be enough?

No.  Some judge somewhere ruled to that effect, so now therre are tattletail lights.
Wait, it's all Ohio? Always has been.

Brandon

Quote from: vtk on November 06, 2011, 07:24:17 PM
Quote from: Brandon on July 12, 2011, 07:08:43 AM
Quote from: realjd on July 11, 2011, 08:13:14 AM
Quote from: Brandon on July 10, 2011, 07:52:24 AM
Quote from: Alex on July 09, 2011, 08:49:17 AM
They use them in the Orlando area too. Within Pinellas County, the lights are simply white. They are known as "rat lights" and indicate when a signal is red for law enforcement. Mobile uses small blue lights affixed to the back of signals for the same way.

We use similar lights around here.  However, they flash for the "green" street, and are solid for the "red" street when triggered by a police car, fire truck, or ambulance.

Those are for the emergency vehicle preemption system. The lights we're talking about down here are for red light enforcement - "rat lights". They're on when the light is red, off when green. It's so a cop on any side of the intersection can catch red light runners without needing to see the front of the signal.

Wouldn't the simple fact that the cross street has a green signal be enough?

No.  Some judge somewhere ruled to that effect, so now therre are tattletail lights.

Obviously it does not apply here as we don't have them and don't need them.
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton

"Symbolic of his struggle against reality." - Reg

roadfro

In the Las Vegas area, they use a dual-color system where a blue light comes on when the signal is green and a red light comes on when the signal turns red (I think, I might have the colors reversed). In Reno, the few I've seen have a red light come on when the signal turns red. In either case, the rat lights are mounted to the back of either the signal pole or a side-mounted signal head attached to the pole to be visible only downstream from the signal--the rat lights are also only installed for through movements. These indicators are not installed at all intersections, but just some that seem to be problematic.

Quote from: Brandon on July 12, 2011, 07:08:43 AM
Wouldn't the simple fact that the cross street has a green signal be enough?

As has been mentioned, the simple fact that the cross street has a green signal is not a simple-enough indication. There are all-red phases (typically short/non-existant in many areas, but in places like Las Vegas that red clearance phase can be as much as 3-5 seconds) and the existence of turn phases (which, especially if there is lead-lag left turn phasing, the through phase can be red upwards of ten seconds before the cross street gets a green). Preemption can be another factor, in that all directions may be red or only one approach may have a green at the time, which is not necessarily apparent downstream.
Roadfro - AARoads Pacific Southwest moderator since 2010, Nevada roadgeek since 1983.



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