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Ambulances will trigger green signal

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Re: Ambulances will trigger green signal

#31

Post by bryondowd »

Hoff wrote: post #27
NLips wrote: post #15

Why doesn't the signal set all lights to red, leaving the junction clear for the ambulance to go through? The best reason I can think of is if the idea is to improve traffic flow in general in favour of the ambulance (e.g. allow cars in front of the ambulance to move on through the lights), but that quicklt becomes a much more complex problem.

Former EMS provider... The laws on whether ambulances must stop at red lights and stop signs vary by locality. It's almost always legally your mess if you don't stop at a traffic control device and are then involved in a collision — most laws and various insurance or service policy requirements tend to require "due care" or "prudent" or other such wording, and collisions are usually considered an adverse indication.…

Just curious what you mean by 'some of the folks at the front of the herd will inevitably not break that red'. I often wonder what I should do when I find myself stuck someplace where I'm possibly in the way of an ambulance at a light.

Most of the time it's as simple as everyone pulling to the right and letting the ambo through the middle, but there's many situations where it just isn't obvious what everyone should do.

It would be great if there was an illustrated guide out there somewhere. I may have to look around.

Re: Ambulances will trigger green signal

#32

Post by imroot »

bryondowd wrote: post #31
Hoff wrote: post #27

Earlier quoted context omitted.

Former EMS provider... The laws on whether ambulances must stop at red lights and stop signs vary by locality. It's almost always legally your mess if you don't stop at a traffic control device and are then involved in a collision — most laws and various insurance or service policy requirements tend to require "due care" or "prudent" or other such wording, and collisions are usually considered an adverse indication.…

Just curious what you mean by 'some of the folks at the front of the herd will inevitably not break that red'. I often wonder what I should do when I find myself stuck someplace where I'm possibly in the way of an ambulance at a light. Most of the time it's as simple as everyone pulling to the right and letting the ambo through the middle, but there's many situations where it just isn't obvious what everyone should d…

That's why EMS drivers love Opticomm and other traffic preemption devices -- The direction that you are traveling gets a green light -- keeping traffic in the direction that you're moving flowing (so, in theory they merge to the right, but, that's another topic for another day) -- and you get protected turn signals (so that traffic ahead pays attention to the red lights at the signal, not your red lights that they may not be able to see or notice.

Re: Ambulances will trigger green signal

#33

Post by DanBC »

bryondowd wrote: post #31
Hoff wrote: post #27

Earlier quoted context omitted.

Former EMS provider... The laws on whether ambulances must stop at red lights and stop signs vary by locality. It's almost always legally your mess if you don't stop at a traffic control device and are then involved in a collision — most laws and various insurance or service policy requirements tend to require "due care" or "prudent" or other such wording, and collisions are usually considered an adverse indication.…

Just curious what you mean by 'some of the folks at the front of the herd will inevitably not break that red'. I often wonder what I should do when I find myself stuck someplace where I'm possibly in the way of an ambulance at a light. Most of the time it's as simple as everyone pulling to the right and letting the ambo through the middle, but there's many situations where it just isn't obvious what everyone should d…

In England: http://www.bluelightaware.org.uk/?p=239

When you're driving you either pull over and slow down (if it's safe to do so); or you keep driving at a safe speed and pull over when it's safe to do so.

If you're at a traffic light you can either try to move to the side without crossing the line; or you can stay where you are and allow the emergency vehicle to sort it out; or you can cross the line if a police officer directs you to do so (and blue lights is not a direction).

Re: Ambulances will trigger green signal

#34

Post by hoop »

lojack wrote: post #20
616c wrote: post #8

What's funny in certain countries (right now for me the GCC) is that people believe if you flash with your brights at the right speed and frequency it will automatically set them to green, or shorten the interval on the opposing traffic direction so it goes green for you sooner. Do other people believe this? I have watched people try for over 60 seconds or more until giving up, and I find this hilarious even today.

I could understand why people would believe this. http://en.wikipedia.org/wiki/Traffic_signal_preemption#Line-... In the US at least, that is how a significant number of these systems work. It's rather unlikely they would get the right frequency to trigger it, but it's certainly possible.

This is spot on and how it was where I grew up and was a volunteer firefighter. IIRC, the visible strobes on our equipment we referred to as "opticoms"

Re: Ambulances will trigger green signal

#35

Post by grkvlt »

monk_e_boy wrote: post #12
616c wrote: post #8

What's funny in certain countries (right now for me the GCC) is that people believe if you flash with your brights at the right speed and frequency it will automatically set them to green, or shorten the interval on the opposing traffic direction so it goes green for you sooner. Do other people believe this? I have watched people try for over 60 seconds or more until giving up, and I find this hilarious even today.

This works for temporary traffic lights here in the UK (I've just googled and some people seem to think they are motion sensors, but from my experience they aren't) If it's dark and quiet, I think both sides go to red, then when a light is detected, that side goes green. Quite common knowledge in the UK

No, sorry - they are motion sensors. I can trigger them on my bike, with no lights involved. You're suffering from confirmation bias, and not taking into consideration the fact that the lights change when they detect your vehicle, this is usually going to be coincident with you flashing your headlights, but the former is the cause, not the latter. It's a common misunderstanding, though.

Re: Ambulances will trigger green signal

#36

Post by toomuchtodo »

hoop wrote: post #34
lojack wrote: post #20

Earlier quoted context omitted.

I could understand why people would believe this. http://en.wikipedia.org/wiki/Traffic_signal_preemption#Line-... In the US at least, that is how a significant number of these systems work. It's rather unlikely they would get the right frequency to trigger it, but it's certainly possible.

This is spot on and how it was where I grew up and was a volunteer firefighter. IIRC, the visible strobes on our equipment we referred to as "opticoms"

Opticoms can be preempted with a strobe light using an IR filter; they don't need to receive visible light to activate.

If the Opticom sequence is trivial, the hardware is easy. If its a complex pattern, a 555 timer is required.

Sitting outside your local fire station recording video of the strobe pattern on an emergency vehicle should be sufficient to determine the necessary pattern (you step through frame by frame to identify the sequence).

The above is informational only. One should keep in mind that today, most traffic lights will log the preemption with their central controller, and that unauthorized use is illegal in most jurisdictions.

Re: Ambulances will trigger green signal

#37

Post by JshWright »

bryondowd wrote: post #31
Hoff wrote: post #27

Earlier quoted context omitted.

Former EMS provider... The laws on whether ambulances must stop at red lights and stop signs vary by locality. It's almost always legally your mess if you don't stop at a traffic control device and are then involved in a collision — most laws and various insurance or service policy requirements tend to require "due care" or "prudent" or other such wording, and collisions are usually considered an adverse indication.…

Just curious what you mean by 'some of the folks at the front of the herd will inevitably not break that red'. I often wonder what I should do when I find myself stuck someplace where I'm possibly in the way of an ambulance at a light. Most of the time it's as simple as everyone pulling to the right and letting the ambo through the middle, but there's many situations where it just isn't obvious what everyone should d…

The short answer is that we will expect you to move forward and to the right whenever possible. Above all, we don't want you to put yourself into a dangerous position.

If you're at a red light with an emergency vehicle behind you, the best course of action might be to make a (safe!) right on red and then go around the block to get back on your original course.

Re: Ambulances will trigger green signal

#38

Post by JshWright »

winsome wrote: post #28
madeofpalk wrote: post #17

The traffic lights in Sydney are managed in a way to give priority to late-running public transport. I was impressed to find out the traffic light system in Sydney, Australia (Sydney Coordinated Adaptive Traffic System - http://en.wikipedia.org/wiki/Sydney_Coordinated_Adaptive_Tra... ) has been exported around the world to cities such as Singapore, Dublin and Hong Kong. Interestingly enough,

SCATS is also used more than you might imagine in some US areas. SCOOT ( http://www.scoot-utc.com/HowSCOOTWorks.php ) is a similar system used in a lot of locations too.

Those are some fantastic acronyms...
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