Government, industry join forces to entrap and endanger motorists.

Not only would I approve red light cameras at ALL red lights, but I would like something similar at all stop signs.

Huh? I never claimed a "majority" of anything...

Yes, "Saving Lives is GOOD". Thank-you for rasing that flag...We all agree with that. Again, thank-you.

But, this is not a simple game of Capture the Flag. (I am not here to capture the "safety flag" you have just raised and drag it off to the camera opponents' side.) This, rather, is a game of SHOW CAUSE AND EFFECT. And it is the vendors burden to show a "legitimate goverment purpose" in these machines, and a quantifiable cause and effect that is in the public interest. That has not been done.

Statistics is not a democracy...It does not care what "Most people believe" as you sited.

The limited claims and highlighted sporadic successes of the red-light vendors just isn't a srong and rigiorous analysis showing cause, effect and a causal link.

I can see it is gratifying you have "been told" your "city has had no fatalities at intersections since cameras were installed". Even better you find solice and comfort in believing that. (Hey, man - whatever floats your boat! I'm not here to upset your apple cart.) But, that is a long way from documenting and establishing a CAUSAL CONNECTION between the two. Nor, is it the only way to acheive the same or better end result.

Rigorous enforcement is an effective way to mask bad engineering. Problem is - reducing volations through better engineering conflicts with the revenue goals of the vendor. So, your left with a system that drags on itself. (If you fix the problem - I mean really fix it - you choke-off the revenue you have become so accustomed.) Who wants to build a machine like that?

A word to the wise...be very wary of anyone that tells you (or implies) we are at a point in our transportation infrastructure that we need to INCREASE some accidents to reduce others.

--------------------

To recap and summerize this thread, " Government, Industry Join Forces to Entrap and Endanger Motorists", since 1985 government has been reducing recommeded yellow-light timing guidelines and recommendations, and red-light camera enforcement vendors have been used as a deterent to (try to) mitigate these reductions. Government lowered the overall safety standards - and "private industry" was suppose to fill in the gap with enforcement.

Half the vendors' revenues now come from tickets issued in the first half-second the light is red. This is before the crossing traffic light has even turned green.

Now, that same industry that wants you to accept law enforcement by private corporation, also wants you to adopt the idea that in order to "attempt" reductions in some accidents - we invariably must accept INCREASES in other accidents. All the while - they enjoy the financial windfall of reduced yellow-light standards.

I anticipate quite a few flames over what I'm about to type but just as the video shows, humans come in a wide variety.

No one could possibly make a 'Money or Safety' decision by simply looking at that startling video.

The one thing you can conclusively say is here are 11 cases of the cameras not preventing red light running and 1 case of a pedestrian misjudgment & violation.

For sure we saw some vehicle operators that probably shouldn't be on the road, or at least need to be remediated. The pedestrian ran across the road well before the light turned red, so I'm not sure what type of camera would help there.

We can surmise all day about the unknown 'others' that were otherwise 'saved' & not shown in the video but it's still supposition fueled by compelling but emotional images of the worst drivers they could capture on tape (hopefully!, but that was the premise-'Top 10'). Hard to get more one-sided than that.

Let me be clear about two points-
First cameras being more for safety or money or more 'good' than 'bad' is not a yes/no, black/white topic for several reasons, and the first reason depends entirely on someones personal scale of reasoning, justice, and acceptable effort/expense.

Second, I think some of the drivers in that video need to be specifically targeted for remediation and/or removal/suspension of driving privileges. Either that or the jurisdiction's licensing methods need scrutiny. If that wasn't done then these are 11 prime examples of where the cameras don't improve safety.

And we haven't even touched on other specific traffic & road engineering issues or whether they were considered or tried.

Thank you for a reasoned approach to the question. The OP's thinking is flawed - accidents at intersections are not caused by red light cameras - they are caused by stupid drivers deciding at the last minute they can't beat the light. Most probably don't even know the cameras are there!

Case in point, there is an intersection in my town that had cameras installed recently. Before they were made active, the town published a note in every local paper announcing the locations and warning when they would be activated. Previously there were dozens of accidents at that intersection because od idiots trying to blow the lights, not paying attention to their driving (cellphones!), etc. Since they were activated there has only been ONE accident in the past 6 months.

How many of you have nearly been T-boned by some idiot blowing a light? I have, and I didn't like it much.

Obey the law and STOP at the damned lights. How much is an extra minute or two of your time worth?

By the way ... the legal definition of "entrapment" is to "provide an opportunity for someone to commit a crime that they NORMALLY "WOULD NOT COMMIT" UNDER NORMAL CIRCUMSTANCES. In my experience - people who blow lights do so regularly. Screw'em.

Yellow lights are timed to allow sufficient stopping time when cars are moving at the posted speed limit.

Yellow Light – Enter the intersection with caution, not speed up to beat the red light.

That's totally bogus the way yellow lights are being times when there is a camera. When the yellow lights are set so short you have to slam on breaks when you first see them. You only have 1 second to make a call on whether to continue or stop. If you stop you run a risk of getting hit from behind.

I drive a black and white all day. I cruse through the yellow lights just like most of you do. Do I speed up to try and beat the Red Light, sure I do, sometimes. Just like most of you do. The red light camera will not take your picture entering the intersection on a yellow light or if the light turn red and you have not cleared the intersection.
The camera will only take your picture when you enter the intersection on a red light.
Remember! There are signs posted stating photo enforced ahead or your GPS alerts the driver of such cameras.
Most of all pay attention to your driving. I have a MDT that I read and impute information into while driving.
I have to be extra careful. I watch out for other drivers who are texting or talking on their cell phones. I don’t like all the paper work there is to do if I get in an accident.
By the way, what difference dose it make if there is a red light camera at the intersection unless you are red light runner?
joemac

Thanks for what you do. My son in law is in law enforcement also and most people have no idea ...

I wish I had confidence that you were speaking on behalf of all jurisdictions in the U.S. Everyone might be better off and a lot less apprehensive.

If it's a still camera solely for the purpose of light violations & used at a properly timed light at a properly engineered intersection, not there to aid more traffic flow through an intersection than it can be expected to safely handle, and reviewed by a law enforcement officer for accuracy & appropriateness ... no difference really. Other than it would be just more appropriate to use another means to stop habitual violators that run through even those lights that already have cameras, imo.

Let me ask you a question:

Which is safer for the general public:

a) A light where no "t-bones" occur because red light cameras have been installed.

b) A light that has been properly designed with proper timing of yellow lights which leads to no "t-bones" or rear-end accidents at the light.

I don't understand why municipalities, counties, and states choose extra revenue over true safety for their citizens.

One last question: How many fatalities did the intersection you referenced have the year before the camera was installed? What about the year before that? I can put up a red light camera and claim that there have been no fatalities since the camera was installed but how does that prove anything if there weren't any fatalities at the intersection prior to the red light camera going in?

No, in 2001 there were 101 accidents on Hixson road in Chatanooga.

And in those 8 years between 2001 and 2009 were there any structural infrastructure changes that removed a bulk of traffic from that road? Didn't the "learer's-permit" rules go through a major overhaul, removing some teenage drivers from the road in Tenneessee? Wasn't there a major reduction in drunk drivers on the roads of Tennessee in that time?

Are all of these other structural and state-wide improvements in overall safety to also be attributed to the speed camera on Hixson road?

Futher, the school, church and urban subdivision were placed on that road, even though the road really wasn't designed for it.

Was the subdivision developer assesed a realistic fee for needed design improvements off-setting the impact the subdivision residents would have on the road? If not, all those subdivision residents bought their houses for less than the cost of their impact on their own community...

Did the school or church's design and permiting cost include design improvemets to the road for the added merging traffic they create?

And that goes to my point. Now that some accidents have been mitigated and the county has a tidy revenue stream from these flaws; you can say good-bye to future design improvements to that road.

Nor, is there an incentive to charge developers for the true impact thier developments have on the community's infrastructure.

-------

So...you want to build a large residential development on a small country road.

So, you go to the county planners, and they say "Sure, we can do that. But we'll need 1.5 million dollars to add a turn lane and widen and straiten that county road for your residential development."

But you say "Improving the road will only increase my costs, and I don't want to pass that on the home buyers. So, I really don't want to pay to make improvements to that road ...and if you try to make me pay, I'll just build my development in the next county over!"

"Sure then...no problem", the county planners say. "We can do that, too. We'll just leave the road as-is, but line it with speed cameras. Problem solved!"

So, the road never gets improved. It takes on more traffic, and in ways it wasn't designed to handle. The developer never has to pay, and they pocket the money. The home owners never have to pay, and they get their houses for cheap. And the county collects revenue from the roads flaws instead of spending money to fix them.

Yes, I can see how it's a win-win for everybody...

We can debate and hold any opinions we want. The best factual summary I have read regarding light timing can be found at http://www.thenewspaper.com/rlc/docs/armey/89intervals.pdf

This was written by the Institute of Traffic Engineers (ITE) Technical Committee 4A-16.

There are a number of speed, distance, reaction times, etc., factors considered and some formulae derived.
However, it is interesting to note that despite all the thought put into the document, the committee had to allow that the optimal timing could not be determined mathematically, but would always depend on judgemental factors.

Especially with finding data on incidents that the right officials don't respond to or don't have a specific checkbox or blank to fill in.

.. and then it has to be collated & made available along with YOU finding someone who actually knows where and is willing to tell you.

Here's a good question for ya':

If red light cameras are so effective why are they not used at rail road crossings?

Why don't we replace all those expensive, flashing mechanical arms with the old, single, flashing-red, railroad light and a red-light camera?

If you really want safety...you have to directly affect the metering and flow of the traffic.

I have see such an equation before. Would you mind taking some sample values and working out the timings. For example a vehicle traveling at 40 MPH (59 fps) on a 5% downgrade.

Why not replace red-light cameras with mechanical arms?

Would you give us some thoughts on the proper metering and flow of the traffic, please?

No thanks.

I would rather keep the question just the way I wrote it:

If red light cameras are so effective why are they not used at rail road crossings?

Must be some reason...

And if that bothers you, TS. No one stops at stop signs when turning right around here, so I say ticket them by any means possible. Trip a red light camera, ticket them by any means. You drive 20 over, take the license.

I do not care if redlight/speed cameras are effective or not in decreasing the level of incidence. That is well left to the myriad of statisticians on both sides of the aisle to fight out. If you ran it, you need to be stopped from running them in the future, and money is more often than not, a pretty good deterrence, at least for a while.

Additionally, a picture helps in locating the car (perhaps not the driver and that again, should be part of a responsible owner's consideration prior to loaning) that left the scene of a collision with car or human. Many indeed do leave the scene as all enforcement agencies readily report...

Hey folks, some of you seem so self centered and spoiled that you have failed to remember one simple thing: it IS a License to drive and it brings with it the requirement to do so by the rules laid down by the good folks you elected to make them, it is NOT a right given by GOD or the Constitution. Don't like the rules, become an effective lobby for changing the timings, or whatever, or go broke doing whatever selfish driving habits you have developed.

If the jurisdiction makes money then good for them. They probably need it for trash collection since their tax base (usually real estate) has been trashed by the similarily motivated selfish, greedy pin heads that have stolen almost everything from the rest of us. There is my opinion about enforcement of ALL the rules this country seems to have generally long ago lost comprehension of. Enjoy your tickets in good health.

As to train crossings, well those folks TRULY need the violent education coming their way, AFAIAC.

Who cares if they make money? It's to improve safety, right? That's why they should give the money to a worthwhile charity since they are only doing it to improve public safety.
Chicago's own Ed Burke had some rather pointed remarks today about cameras:
http://newsblogs.chicagotribune.com/clout_st/2010/03/ald-bur...

About 4.5 secs

Sorry, but that's about all I'll remember from your dissertation.

I don't believe in rlc camera being the solution. DEfensive driving IS!!!!!

Hawaiian Flyer,

Would you please give us your thoughts on the proper metering and flow of traffic?

And I too will try again...

If red light cameras are so effective why are they not used at rail road crossings?

Hawaiian Flyer,

Slightly rephrasing the question to see if it still makes sense: “If red light cameras are so effective, why don't we replace all those expensive, flashing mechanical arms with the old, single, flashing-red, railroad light and a red-light camera?”

“If red-light cameras are so effective” is not, to my way of thinking, an appropriate or complete question considering the reasons for and against red-light cameras that have been proposed in this and other similar discussion threads. Effective at what?

First, we are not concerned with the safety of the train. If the driver who “runs” this red light t-bones the train, I suspect that the train would be relatively unscathed.

Next, I have never seen (although there may be some) a railroad crossing that has a yellow light before the old, single , flashing-red, railroad light. That changes the situation significantly. I have rarely seen someone go across the railroad track without slowing down first. Of course, there would be situations where the lines of sight in both directions would be sufficient to allow a driver to determine that there was no danger in “running” the railroad crossing. Just a possible are lines of sight that would cause even the most macho driver to slow down dramatically before proceeding.

Consider the last car to pass over the rails just before the railroad red light started flashing. Do we really care if another car “runs” the now flashing-red light? The car “running” the flashing-red light probably is not a danger to the last car that went through. Without the mechanical arms, I have seen many drivers stop at the flashing-red light, look both ways and then proceed. Perhaps you have done this yourself.

I suspect that most drivers - even those that routinely try to beat the yellow light - would be more cautious at railroad crossings. This impacts the question in ways I do not know how to evaluate.

Also, it is the railroad that has been required to provide the lights or arms in order to alert drivers that the train is coming. I do not know whether it is against the law to “run” a flashing-red light at a railroad crossing. Can anyone comment on this?

Now to the question of “effective” at what.

Effective at revenue generation: Many people claim this is the purpose of cameras. So, if we applied this to a rail road crossing - that is, we used a well posted red-light camera in addition to the flashing-red light (instead of mechanical arms to stop traffic) - I suspect that most people would stop. It would almost seem like the municipality would be “daring” a driver to cross on red. this would mean that that revenue would drop and thus that red-light camera would not be effective.
Effective at Safety: As mentioned earlier, safety of the train is not the issue. Will rear-end accidents go up because there is a red-light camera in addition to the flashing-red light. I do not think that the presence of the additional red-light camera would have any relevance to such accidents. Drivers stop because they don’t want to be hit by a train, not because they are worried about getting a ticket. I’ll call this moot.

What other elements of effectiveness should I address?

Thanks!

But, you didn't answer the question...

Why are they not used at rail road crossings?

Hawaiinflyer,

I thought I had answered your question. I'll rephrase and paraphrase. Railroad crossings are not the responsibility of the municipality, but the railroad. Therefore red-light cameras - which are under the control of the municipality - are not of value (safety or revenue) to the municipality.

To add another thought - the decision to use the more expensive arms (versus the flashing-red lights) is likely a function of the "close calls" at the crossing.

Have you worked for the railroad?

By and large, the cameras are about the money and the cameras should be banned. If there are real problems with red light runners, let real police officers give them citations.

Yes, that is somewhat more clear and concise. (Though I have no understanding of your sentence, "Therefore red-light cameras - which are under the control of the municipality - are not of value (safety or revenue) to the municipality".)

But, I can see you mean it is a technical issue of jurisdiction that prevent red-light camera applications at RR X-ings. And that is a very good answer!

Issues of jurisdiction aside, though - it is clear the application would be physically dangerous. And, to me at least, that seems more to the point and yeilds a "more complete" answer.

No. Besides shares in various "Transportation Indexes" I have no financial connection with the RR's.

Will this topic never go away? It's been around for months! (Don't drive like an idiot and you'll be okay.)

I'm a public servant. I work for the U.S. Govt., who exactly has the lavish pensions, health plans and life time security jobs? You may know lots about traffic lights, however, you know absolutely nothing about public servants! Stick with what you know.

I agree with you 110%!! If ya can't do the time, don't do the crime!

I have no problems enforcing the vehicle safety laws. What I do have an objection to is that some localities engineer situations in which motorists can hardly comply with the set up at an intersection. This earns tons of money, which the localities need during these tough times. Citizens are having tough times too. Robbery is still a crime whether it's commited by an individual or municipalities.

We don't need Big Brother who has an intent to collect cold cash. We do need enforcement that prevents careless or bad motorists from causing mayhem.

Fred

I've never received a ticket by a red light camera or a speed camera. Of course everybody should obey all traffic laws.

But the shortening of the yellow duration by a second or two is just plain sneaky and underhanded. I believe it is a flagrant abuse of power by a village, city etc.

Our cars have become rolling atm's.

Furthermore, why are police allowed to break traffic laws when there is no emergency? They make U-turns, speed, block fire hydrants and park in no parking zones, when there is NO EMERGENCY.
Do a search for "Jimmy Justice" on YouTube. He video cams police breaking traffic laws when there is NO EMERGENCY. "like picking up something at a Rite Aid"

BOB - Akron OH

Many posts in this thread complain of short times for the yellow light. None that I have read give any quantitative date. Fro example, the recommended time for a yellow light at an intersection in a 40 mph zone, is about 4.5 secs. If, in order to speed up the traffic flow, the time were decreased to 3.5 secs, then it should still be possible for a driver to come to a standstill in time.
Of course, this assumes the driver is paying attention and is driving properly for the conditions and the mechanical condition of the car.
What is the duration of these short yellows that posters are complaining about?

Red lights Oh I should STOP think of that ????

There are plenty of threads with timing and reaction time discussions & specifics. Even earlier in this one.

There is a link to an article with an educated opinion here http://www.poi-factory.com/node/27444

Traffic flow along with the money incentive are probably the two biggest reasons that safety gets compromised. And some feel it's just wrong to rely on the cameras as the de facto intersection safety silver bullet when it simply isn't.

So if 4.5 sec is recommended, it's ok to reduce that to increase traffic flow?

To address your question, when you're doing the fps math, remember the 2 to 2.5 second average reaction time regardless of speed.

There is a article that is often referenced by opponents of red-light cameras. It may be found at
http://www.thenewspaper.com/rlc/docs/armey/89intervals.pdf

This article says that the recommended reaction for the driver is 1.0 second.

Wikipedia has an article on Reaction Time. It may be found at http://en.wikipedia.org/wiki/Reaction_time

Reaction time is measured in fractions of a second. They point you to sites online in which you can measure your own reaction time.

You have quoted 2 to 2.5 second average reaction time. Could you please provide a link to the article recommending such a long reaction time?

Nothing will change, and exactly because this is not some isolated phenomenon, but logical and predictable trend, one of 1,000, when government is serving the true citizens of this country - the corporations. We can argue as much as we want against speed traffic cameras as well as against insane wars that nobody can even explain, all this is falling on the dead ears. The politicians are getting paid by corporations, and obviously they work for their employer. Everybody would do the same, not to blame anybody in corruption. The recent decision by Supreme Court that corporations can bribe the government without limits only confirms all this. Things will not change unless we address the core problem, by eliminating the corporate "person" as such from the society.

Nothing will change, and exactly because this is not some isolated phenomenon, but logical and predictable trend, one of 1,000, when government is serving the true citizens of this country - the corporations. We can argue as much as we want against speed traffic cameras as well as against insane wars that nobody can even explain, all this is falling on the dead ears. The politicians are getting paid by corporations, and obviously they work for their employer. Everybody would do the same, not to blame anybody in corruption. The recent decision by Supreme Court that corporations can bribe the government without limits only confirms all this. Things will not change unless we address the core problem, by eliminating the corporate "person" as such from the society.

vrap-I agree with much of what you say in general, but IMHO, we still have to fight injustice daily, in each of our "little worlds".

A corporation is typically a body representative of shareholder interests primarily involving profitability but can also include principles such as sustainability. As I understand, individuals do not lose their rights when they are represented as a collective body. Why do you think that the act of banding together in common interest diminishes their rights? For example, is the corporation or more correctly, the CEO as the representative of the shareholders, accorded any protection under the Fourth Amendment against illegal search and seizure?

Most of the outrage surrounding the Citizen United v FEC is due to misunderstanding which corporations would benefit. The common assumption is that companies such as ExxonMobil would have an unequal voice in the political process, but what of entities such as public employee unions or other advocacy groups?

I do agree that the concentration of power is an issue but how do you deal with it? With some restrictions, corporations were already allowed to influence the political process through the use of PACs and other means such as public relations.

The question should definitely be raised when the corporation runs contrary to certain issues of grave importance including national sovereignty, in other words, when the interests of the corporation run counter to the general welfare of the American people. In this case, the power of the corporation should be scrutinized. In reference to this specific instance, laws exist that control exportation of certain technologies and information to some markets.

Note also that SCOTUS has ruled in favor of collective bodies such as that representative of the public interest in cases such as Kelo v the City of New London. Though I don’t necessarily agree with this ruling, it brings up an issue.

It’s been said the US Constitution and Bill of Rights is virtually silent on the central right of property. You can still lose your property legally as there is no legal recourse when the seizure occurs under the due process of law.

Despite the common conception of the Constitution and its Amendments perhaps the issue was stacked against us from its very origin through the pervasive influence of the Federalists.

It's from the section on Brake Reaction time, 1994 edition of AASHTO's A Policy on Geometric Design of Highways and Streets (pp. 118-119)

To be completely fair, the 1989 article you mentioned suggests 1 second as a starting point and "measured for effectiveness" by monitoring the percentage of vehicles entering the intersection after termination of the yellow and in the red phase and adjusting the yellow duration accordingly.

The Wikipedia entry is for general reaction times, not specifically in a highway environment.

And, the AASHTO times I quoted, while specifically for highway environments, are not limited to reaction time & stopping distance at signal devices alone. Although I seem to recall in the past that this AASHTO document was used in calculating the cycle times recommended in the MUTCD.

Regardless of which reaction time you used in your 40 mph/4.5 sec example.. now please answer my question.

If 4.5 sec is recommended, are you saying it's ok to reduce that to 3.5 sec in order to increase traffic flow since it's theoretically possible to stop in time?

How is that methodology functionally different than speeding up to get through the light? Both err toward moving vehicles through at the expense of safety.

{quote}There are plenty of threads with timing and reaction time discussions & specifics. Even earlier in this one....[/quote]

The only post I could find that actually quoted times was one that said the timing was 3.5 secs in his neighbourhood. I couldn't tell if the speed limit was 30 mph, 50 kmph or 60 mph. In my area it's 3 sec at 50 kmph (31 mph), and 3.5 sec at 60 kmph. Most drivers seem to be able to stop with no problem. The red light runners are most always those at the end of a line-up. It's not a braking problem, it's an impatient problem.

However, I understand your position. You require about 2 to 2.5 secs to recognize a light and make a decision. You also require more than 75 feet to stop from 40 mph.
You obviously recognize your own capabilities and wish to have the yellow lights timed to allow for your specific needs (and for those having the same capabilities). The green must turn to yellow when you are more than 230 feet (greater than 12 car lengths) away, and remain on for more than 5 secs in a 40 mph zone.
In a 60 mph zone, the light would need to change when you are more than 375 feet away and remain on for more than 10 secs.
If that's what you need then that's what you need.

If you're looking for specific timings at specific lights then you're correct that there are very few, but reaction time and stopping distances can be very specific to each individual location for a variety of reasons with posted road speed only being one. You also need to follow the links and apply the recommendations to answer your question.

I don't think you do, but for the sake of discussion let's go ahead and assume that I was making up recommendations based on my own driving skills.

I'm not quite sure what formulas you used or why you're suggesting these would apply to all signals, but they wouldn't. If you were talking about general stopping sight distances (not specifically signals) then you would actually be shorter than the 2001 AASHTO recommendations of a median 305 ft at 40 mph and 570 ft at 60 mph.

But those distances are not at all what I would suggest for all traffic signals. In fact I'd leave the suggestions to those that have studied the subject. And they advise that signal timing is a complex process that depends on among other things the posted speed, general visibility and distraction factors, which lane (turning, straight through, etc) is being stopped, the number of lanes crossed, total intersection width, and something you rarely see these days .. the cross traffic green delay after the crossing street's red. And the MUTCD does recommend a delay in most situations.

Probably the most relevant recommendation (imo) to consider in these timing discussions though if we are concerned with "saving just one life" is this quote from the 1994 AASHTO Green Book-
". . . In the determination of sight distance for design, the reaction time should be larger than the average for all drivers under normal conditions. It should be large enough to include the reaction time required for nearly all drivers under most highway conditions."

The following excerpt was taken from the 1994 edition of AASHTO's A Policy on Geometric Design of Highways and Streets (pp. 118-119).

"Brake reaction time is the interval between the instant that the driver recognizes the existence of an object or hazard in the roadway ahead and the instant that the driver actually applies the brakes. This interval includes the time required to make the decision that a stop is necessary.

Under certain conditions, such as emergency conditions denoted by flares or flashing lights, operators accomplish these tasks almost instantly. Under most other conditions the operator must subconsciously associate the object ahead with stationary objects adjacent to the roadway, such as walls, fences, trees, poles, or bridges, to determine that the object is also stationary or moving at a slow speed. These determinations take time, the amount of which varies considerably depending on the distance to the object, acuity of the operator, the natural rapidity with which the driver reacts, atmospheric visibility, the type and the condition of the roadway, and the type, color, and condition of the hazard. Vehicle speed and the roadway environment probably also influence reaction time."

I'll admit that I have not read the complete AASHTO Policy, However, from what I can descern, they are not talking about traffic lights but about hazards that appear in the roadway, such as a biker on the side of the road ahead.

Indeed, they say that the reaction time to flashing lights is almost instantaneous. So, I will need to do more research to see how the Policy statement is applied to traffic light situations. It seems to me that the Traffic Engineers recommendation of 1 second has taken the AASHTO into consideration, but I have no definitive statement to that effect.

Now to your question: If 4.5 seconds is the recommended value, then I do not think it would be proper to reduce the timing in the interest of traffic flow. Safety, in my mind, should override any such thinking.

I do not really understand "How is that methodology functionally different than speeding up to get through the light? Both err toward moving vehicles through at the expense of safety." I am assuming that the "methodology" you refer to is reducing yellow light time - which I think is improper. If that is what you refer to, then I agree that both the reduction option and the speeding up would move vehicles BUT at the expense of safety.

Yes, it is referring to all reaction times for stopping sight distances. Constantly flashing lights (provided they are immediately visible) I would also take to need the least recognition & reaction time. Similarly a pedestrian at night the longest, etc. But I think we both get the idea and that even among those agreed upon 'ball-park' statements, then we need to consider response times of most drivers, in general. I'd probably be willing to split the difference between the 1989 ITE 1 sec with practical adjustments, and the 2.5 sec AASHTO higher (but not the highest, btw) to maybe a generalization for discussion of 1.5 to 2 sec. But I think the fed MUTCD has already used the appropriate number in their recommendation figures. The only caveat to them is that they recognize that each intersection needs to be evaluated on it's own merits and as such only gives a range of 3 sec minimum and 6 sec max, along with a red/green 'clear time' of 6 sec max. That range would seem to imply short for lowest speeds & long for highest, but speed alone wouldn't be the rule to live by, imo.

Yes, that's the methodology I was referring to. It seemed as though you might have been entertaining the thought that it would be OK to find a shorter yellow time if the goal was to aid traffic flow. I don't see that as much different than an individual making a judgement call that it is ok to speed up to avoid having to stop. Sometimes it MAY be appropriate, but likely that most times it wouldn't, imo. I'm glad you agree that traffic flow isn't a proper rationalization for short yellows.

The really dangerous situations are when people blow through red lights after they've already changed for a few moments.

Someone tailing through a red light at the end of a long line of traffic isn't really much of a danger.

The problem is that Red Light cameras do nothing to stop people who blow right through stop lights - the real danger.

There are very few people who intentionally blow clear red lights. It happens because of inattention. Red light cameras do nothing to change that.

Additionally, those who are conscientious drivers will stop abruptly in fear of the ticket and camera thus creating more non-serious accidents.

Likewise, when municipalities tinker with yellow lights, dire consequences can result.

The people who blow through red lights are certainly one of the classes of dangerous drivers that red-light camera are intended to catch - and by catching them change their behavior. So I do not agree that red-light camera do nothing to stop them. I also do not agree that inattention is the principal reason. Speeding up to blow the light can certainly not be due to inattention.

That is not to say that inattention is not a culprit in red-light running. However, red-light cameras -well posted - have seemed to work well in bringing at least that red-light to the attention of drivers in my city. There is one set of red-light cameras in my area that have never been turned on. Yet, the accident rate post- camera is less that half that of pre-camera. No citations have ever been issued, but the presence of the installed camera has changed driver's behavior.

While I agree that someone tailing a line of cars is not much of an accident risk in that instance, the fact that they have done so marks them as someone who will flaunt the law - making them possible actors in the blowing the red-light situations.

If the yellow light timing is set properly, conscientious drives do not have to slam on their brakes. They simply stop in a controlled fashion. I note again that a red-light camera not in operation has reduced accidents by over half.

You seem to have assumed that municipalities "tinker" with yellow lights by always lowering them - resulting in "dire consequencies". What if they rather lengthened them as many opponents of red-light camera say is the alternative to cameras?

Just saw a story on how much Chicago took in last year, even though it's about public safety and not money-64 million dollars in fines!
http://www.myfoxchicago.com/dpp/news/metro/20100308-chicago-...

When the red lights start flashing, you are required by law to stop even though the train is still 20 seconds away. If gates are present, the red lights flash for about 3 seconds before the arms start coming down. This delay insures that vehicles can clear the tracks before the arms come down & the train arrives. Occasionally policemen will ride on a locomotive through a town. He radioes to a black & white who tickets the offender. A camera could be installed but because the crossing signals only activate a few times a day, very few opportunities exist for violations... I personally have witnessed many drivers getting cited for stopping in the striped zone of RR tracks while waiting for a traffic light even though the RR signals were not activated. In that case maybe a camera could be programmed to catch those violations.