Red light camera traps: Does science prove our yellow lights are too short?

It could be the biggest money making scheme ever—red-light cameras, synched with short yellow lights, making it physically impossible for drivers to avoid a ticket.

“The laws of physics are unbreakable,” said Brian Ceccarelli, a physicist living in Raleigh, NC.

Ceccarelli and fellow physicist Dr. Joseph Shovlin have been leading the charge against the red-light camera industry’s cash cow–short yellow lights.

“They are catching people not doing it on purpose. It’s beyond their control,” said Dr. Shovlin.

To explain the yellow light trap, Ceccarelli and Shovlin took NewsChannel 3 to an intersection in Raleigh with red light cameras.

If drivers have a proper yellow light time, there should be no problem.

“They have time to stop safely and comfortably, or time to proceed through the intersection before the light turns red,” said

In reality, though, there are always problems–because Ceccarelli and Shovlin say yellow lights, especially in turn lanes, are just too short for the distance needed to travel.

Creating what’s called a “dilemma zone” for drivers.

“If you are in this zone, you do not have the distance to stop and you do not have the time to proceed. You will run a red light, because you have no choice,” said Ceccarelli.

The root of the problem, they say, comes down to the formula endorsed by the Institute of Traffic Engineers, used in both Virginia and North Carolina.

“The formula only works for straight-thru lanes,” said Ceccarelli.

Not left hand turn lanes–yet traffic engineers still use it, trapping drivers into an unsolvable decision: slam on your brakes and hope you stop in time without getting hit by another driver, or running the red light.

“You are hosed, you miss it by a fraction of a second and the red light camera`s got you,” said Ceccarelli.

So how did hundreds of thousands of traffic engineers around the country get bamboozled by this so-called incorrect formula?

Ceccarelli says many of them have no clue what the formula even means.

“This is Physics 101, you should know this. I shouldn`t have to explain Newton`s laws of motion to you,” said Ceccarelli.

In 1959 the first yellow light timing formula was created by three physicists.

The problem came in 1965, when Ceccerelli and Shovlin say that formula was miscopied into the 3rd edition of the Institute of Traffic Engineers handbook.

“The Traffic Engineering Handbook is like the Bible that engineers use, so once you get it in there, it’s like the words of God,” said Ceccerelli. “Traffic engineers don`t know any better, so the red light camera companies take advantage of the situation.”

So how does this apply to Hampton Roads?

Take, for instance, the 3.0 second left hand turn yellow light at St. Paul’s Boulevard and Brambleton Avenue in Norfolk—according to Ceccerelli and Shovlin, it should really be 5.4 seconds.

At the intersection of Jefferson Avenue and Oyster Point Road in Newport News–their 3.2 second yellow should be at least 6.1 seconds.

As for the 4.2 second yellow light at Independence and Virginia Beach Boulevard in Virginia Beach—it should be at least 7.6 seconds.

“The lights are 2-3 seconds shorter than what they should be, and because Mother Nature doesn`t like to be fooled that way, it causes many drivers to run red-lights,” said Ceccerelli.

All while local cities, along with the red-light camera companies, cash in.

“For 40 years, the errors were there, but we never knew about it,” said Shovlin. “It’s not until you put in the red-light cameras going 24 hours a day, 7 days a week, catching everybody who is a tenth of second off.”

For more information on the work Ceccerelli and Dr. Shovlin are doing, just head to http://redlightrobber.com

57 comments

  • dcy

    I think we need more red light cameras. In the Greenbrier area I’ve seen up to 5 cars crossing in front of me while my light is green. There is no constitutional right for anyone to run a light and cause major personal/property damage.
    However, yes, I believe the yellows should be fair and would be if the red light camera companies weren’t raking in 50% or more of the fines off the top. Now there’s where the problem is – allowing private companies to stick their hand in the taxpayer pocket.

  • Bob

    How is having a too-short yellow light increase safety. And yet these cameras force our elected officials to stand up and lie to us. It’s all about safety, they say. It’s not about the money. When they say it’s not about the money, it’s about the money.

  • James Walker

    There are two scams to red light camera cash registers. One is the yellows deliberately set too short, causing many safe drivers to inadvertently trip the red. The second scam is to ticket safe slow rolling right on red turns or drivers stopping just over a line before proceeding. Federal research shows only 0.4% of crashes at signalized intersections and only 0.06% of crashes with an injury or fatality also involve a right on red turn. Virtually all right on red citations are money grab scams.

    Unfortunately, bills to force better yellow intervals or ban the cameras statewide have both failed in the House. There will be NO relief from the legislature to reduce the scams this year in Virginia.

    Relief will come only city by city when engineers are convinced to fix the yellows and to not ticket safe right on red turns.

    James C. Walker, Life Member-National Motorists Association

    • dcy

      James – rolling through a red light to make a right hand turn is always illegal, whether there’s a red light camera or not.

      • James Walker

        Correct dcy, slow rolling right on red turns are technically illegal. So is going 31 mph in a 30 zone. Neither causes safety problems. The slow right on red turns is only profiteering by for-profit camera companies and their for-profit city business partners. Remember, engineers now use an all red, usually 1 to 3 seconds long. Then the cross traffic must perceive the green and start moving into the intersection. On narrow intersections with short all red phases, the safe time for the turning driver is at least 2 seconds into the red. On wide intersections with long all red phases, it may be as much as 7 or 8 seconds.

        Are right on red tickets about safety, or money? In over 99.6% of the cases it is money.
        James C. Walker, Life Member-National Motorists Association

        • dcy

          If there’s a cop behind you, you’re going to come to a complete stop to avoid getting pulled over for a face to face ticket. Why not come to a complete stop at an intersection with a red light camera to avoid the mail ticket? To me, it just seems like common sense. If someone is in that big of a hurry they need to run red lights, to me, they should have left 5 minutes earlier.

          • James Walker

            For dcy; In the absence of cameras, traffic flow and efficiency of operation are enhanced by people who slow to 7 mph, see the way is clear, and proceed without stopping. It reduces congestion, air pollution, noise pollution, fuel consumption, trip time. It reduces the need for additional roads or lanes and improves the overall capacity of the road system as it exists.

            Now consider the worst abuse. You are car # 2, 3, 4, etc. in the right turn lane. Car #1 stops, sees nothing is coming, and proceeds to turn. Cars 2, 3, 4, etc. are at walking speeds and can also see that nothing is coming. What possible purpose is served by having them stop?

            Traffic enforcement for safety is great, for profit is abusive profiteering.

            James C. Walker, Life Member-National Motorists Association

        • steve

          James, I understand but the problem is human nature – some folks always pushing the envelope. Red means stop so some folks merely slowing down. If the rolling red became acceptable, what’s the next step? The next step is what happens to me too often – rolling turners cutting me off when I have a green arrow.

          I don’t have any evidence but suspect that would diminish if folks got the message that stop means stop. The 0.4% that you mentioned has in part, caused my insurance to be too high.

          • James Walker

            For Steve: Remember, that 0.4% is data from ONLY signalized intersections which are only a fraction of all crashes – and it includes the crashes where the drivers were DUI, medically impaired, fleeing police, failed to see emergency vehicles, etc. These are drivers that cameras do not affect. Maybe this part of all crashes adds $1 or $2 to your annual insurance bill, if that much.

            Slow rolling right on red turns are almost always harmless, at least those that occur up to 2 or 3 seconds into the red. I would have NO problem in ticketing right on red turns where the video reveals a failure to yield of the type you mention. This would be far too tiny a percentage for the cameras to even pay their own high costs (typically $4,000 to $5,000 per month per camera on a lease).

            The rarity of these crashes is why you do not see enforcement by officers because the safety payback is too tiny.

            James C. Walker, Life Member-National Motorists Association

  • Brook

    WOW!!!! Stupidity is running amuck here! The purpose of the Yellow Light is to allow cars already in the intersection to clear so that the next approach to get the green light will not hit any cars still in the intersection. I am not a math wiz by any means but PLEASE tell me how it takes me LONGER to stop my car traveling 30mph then it does if I am traveling 35-45mph???? I remember quite well from my basic high school physics class and drivers ed that it takes longer to react and stop the FASTER you are going!! A few other things that were learned if you didn’t sleep through drivers ed is that a Yellow light is cautionary which means you need to slow down and prepare to stop, it does not mean to speed up to race the light! When you are making any turn right or left you should be traveling slower to maintain control of your vehicle and stay in your lane. Also when it pertains to allowed rights on red, you must bring your vehicle to a full stop and look to make sure it is safe to turn then proceed in to the intersection.

    Also if the cities were trying to rip you off why are they only charging $50 per red light offense, not charging you court costs unless you challenge the ticket and not reporting the ticket on your driving record which means no points against your license? IF it truly were about the money and a racket like every one claims, then the city should go ahead and do the following three things!
    1. Charge the full $100 per ticket which is the fine in the state of VA for failure to obey a traffic signal or stop sign.
    2. Charge you the local court cost which is $55-$75 depending on where you go to court.
    3. Assess the standard points against your drivers license. Which if your job is dependent on a clean driving record then you will also have to pay for a driver improvement class!

    Each red light offense is certified by a sworn police officer that compares video and photographic proof that you drove through the intersection a full half second or more after the light turned red. If they see you come to a complete stop even if it is just past the stop bar but the key word is to STOP at the red light then you will not get a ticketed. If the same officer were to physically sit at the intersection and pull you for a red light violation you would not have had that half second lag time before the system starts recording red light violations and it would be his word against yours with out video and photo proof.

  • James Walker

    For Brook. The purpose of the yellow is for drivers near the decision point when the yellow stares to decide whether to stop or go on through. Yellows have not been used to clear the intersections for several decades — all red phases do that job better.

    Yellows need to be slightly longer for turn lanes because vehicles slow from the constant speed the straight through yellows are timed for. It is very easy to find yellows that are MORE than 0.5 seconds too short for turn lanes – it is part of the deliberate scam to make camera profits.

    And fining people for not quite stopping at right on red turns when only 0.06% of crashes with an injury or fatality involve a right on red turn is abusive profiteering – not a safety program.

    James C. Walker, Life Member-National Motorists Association

  • Leo

    The reason why the fine is $50 rather than a full $100 is to discourage people from fighting it. Less challenges means more payments, and they will collect way more $50s than they would $100s; not to mention court dockets would not get clogged up with people fighting their tickets. ALL traffic fines have nothing to do with safety; any honest cop who’s been on the force long enough will tell you that it’s simply a source of revenue. Basically, a legalized scam. In addition, there have been numerous studies that shown zero impact of tickets on road safety.

  • Chris Woolard

    Red light cameras have turned stop lights that were designed for traffic safety, and flow control, into revenue generators. It’s plain and simple and it’s physics. While its doubtful that the facilitators of these red light installations understand the physics involved, they most likely can extrapolate the odds that a fair amount of people will have trouble coordinating a decision down to less than a millisecond! or less than 1/1000 of a second! I say less than because electrical current travels at close to the speed of light, and the drivers “accuracy” has to be at, or better than, that level. The “accuracy” would be the point in time at which the diver decides to initiate the stop or continue without actively knowing the duration of the light, all the while calculating an infinite number of variables all in less than a millisecond. It would be similar to catching an object traveling at the speed of light (without moving) until it was launched. Sure you could just hold your hand out all the time so you dont miss, or you could just stop at green lights. Bottom line, humans are simply not that precise, and that simple fact is exploited.
    In addition to this is the right turn lane stop thresholds appear to be tangent to the straight lane stop thresholds therefore blocking line of site to crossecting traffic. This inherently causes the driver to look to the left and continue past the threshold before stopping just to acquire a visual. At that point you crossed the line and missed sign that says “Stop Here”. Coincidence ? Heres an idea, lets make every runway the same length. Make it suitable down to the millimeter for one type of aircraft to land in perfect weather. Then let’s require all aircraft to land in all conditions without any room for error.

  • Amy

    Wow, the idiocy here is astounding.

    So, let me get this straight, gentlemen claiming to be physicists. The time required to stop a vehicle THAT IS ALREADY SLOWING OR HAS ALREADY SLOWED DOWN TO MAKE A TURN is longer than that which is required to stop a vehicle traveling at the 85th percentile speed (i.e., proceeding straight through the intersection). Is that your argument? Should we now throw out all OF Newton’s and Euler’s Laws of Motion? Oh, and common sense while we’re at it?!

    Unbelievable.

    Shame on you, WTKR, for regurgitating what is easily proven laughably false.

    • steve

      I’ll spare you a return of the condescending tone and presentation – They didn’t say that yellow lights were too short only in turn lanes. They said “especially” in turn lanes.

      Second, the shortest distance betwen 2 points is a straight line….a curved line is longer. That’s not idiocy, it’s geometry. And if the light turns yellow when you’re 10 feet from the stop line and “slowed” to 35 mph, Newton & Euler would tell us that slamming on brakes isn’t a good idea.

      • Dan

        Curved line? all the stop bars are in one straight line for all lanes of traffic. You have pleanty of time to stop when the light turns yellow, the problem is people are use to pushing the lights, when they get a ticket, they look for an excuse.

        Red light cameras work, they reduce the number of aggressive drivers and change bad driving habbits in responsible drivers.

        Red means stop.

        • steve

          I’d like to see you make a turn by proceeding in a straight line. By definition turns are always a curved line. The issue is time to clear an intersection and, no there isn’t always enough time to safely stop. Usually is, but not always.

      • Amy

        If the signal turns yellow when you are 10 feet away from the stop bar, while you’re traveling anywhere close to a reasonable rate of speed, you will absolutely not be able to stop your vehicle before the stop bar. And there is absolutely no way you will enter the intersection on a red signal. You will therefore absolutely not receive a ticket.

      • Amy

        If you’re talking about curved lines in relation to the turning vehicle’s path through the intersection, then I’m not sure you understand these cameras. The cameras are only activated if a vehicle enters the intersection after the signal has turned RED. If the signal is still yellow when the vehicle begins its turn (which happens after it crosses the stop bar if the stop bar is placed at the right location), there will be no violation.

        • steve

          Amy – I didn’t know that. I thought it was a motion sensor activated when the light turned red. Thanks for the information…

          For me, that only leaves the issue of yellow being long enough to safely stop and to clear the intersection for those who can’t safely stop. Usually not a problem but at some intersections it is.

      • Amy

        First of all, you are correct, my condescension and tone were too harsh. Sincerely apologize for that.

        Secondly, they stated that “the formula only works for straight-thru lanes.” If the argument is that the yellow interval is too short for turn lanes, then it’s way too short for thru lanes. It can’t be too short for turn lanes only, because of the actual physics involved. That is what I was trying to say (far too condescendingly).

  • James Walker

    For Amy: IF THE INTENTION IS TO STOP, you are correct. But if the intention is to keep going and complete the turn, then the slower speed than the 85th percentile takes longer to cover the same distance.

    If the light is timed for 35 mph straight through, and it is reasonable to turn the corner at 15 mph, then the person is going an average of about 15+35 divided by two or about 25 mph. It takes longer to cover any given distance at 25 mph than at 35 mph.

    What happens is the person FALSELY believes the yellow is set long enough for turning vehicles, slows from 35 to about 15 as they get close to the stop line – and then the light turns red just a bit too soon. They face the choice of completing the turn with a violation of (for example) 0.8 seconds or panic braking with risk of being hit from behind.

    It is a planned and vicious dilemma zone designed to increase ticket revenue from safe drivers tricked with too-short yellows.

    James C. Walker, Life Member-National Motorists Association

    • Dan

      Thats makes some sense, slower vehicles do take longer to travel a given distance than faster vehicles.

      However, you make one very big mistake. Yellow lights mean get ready to stop, a red light is coming, not slow down and take your time turning.

      Your misconception of the traffic signals is a major flaw in your argument. The following excerpt is taken from the Virginia DMV Manual explaining what to do at a yellow light.

      “Yellow light or arrow: A yellow light or arrow are cautions
      warning that the light is about to change. If you have not
      entered the intersection, stop;
      or, it is unsafe to stop, cautiously
      go through it. If you are already
      in the intersection, go through it
      cautiously. Do not speed up to beat
      the light.”

    • Amy

      Thank you for bringing up dilemma zone, as that has a little more validity than the “it takes longer to stop because you’re turning” argument I got watching that clip. Dilemma zone really is a function of driver behavior – it is a fuzzy area of driver psychology that is mostly unrelated to Physics. If a driver sees the signal turn yellow at a distance away from the stop bar and is unsure about whether he will be able to stop his vehicle in time, that is what is commonly referred to as the dilemma zone. Pretend two vehicles are traveling towards an intersection during the green interval for their phase: the first is going to turn, and the second is going to go straight. Assuming the turning vehicle’s driver sees that yellow change interval begin at the exact same time as the thru-moving vehicle’s driver, they each have the same distance across which they will be traveling before reaching the stop bar. If the turning vehicle is traveling at a slower rate of speed than the thru-moving vehicle, that vehicle will be easier to stop. The driver may not necessarily think this through, but physics says that the slower-moving vehicle is going to take less distance to come to a stop. This indicates that the dilemma zone for the thru-moving vehicle is the controlling factor, with regard to how long the signal should remain yellow. The yellow change interval calculation tries to take this dilemma zone into account with the perception-reaction time factor, but driver behavior is difficult to predict. What this tells me is that if the yellow change interval time is too short for turning vehicles, then it must also be too short for thru-moving vehicles. It cannot only be too short for slower vehicles, because physics does not operate that way, and there is no reason to assume turning vehicles’ drivers have to spend more time deciding whether to stop than faster-moving vehicles’ drivers.

      • James Walker

        For Amy: The Dilemma Zone has a specific definition. It is a range of distance from the light that the drivers in that range have neither enough distance to stop at a reasonable deceleration rate (usually taken as 10 feet per second per second) nor enough time to get past the stop line before the light goes red. The key issue here is that the dilemma zone is DIFFERENT for turning lanes than straight through lanes. The straight lane yellows were fixed in January 2013, the turn lane yellows remain illegally set.
        James C. Walker, Life Member-National Motorists Association

    • Amy

      You’re correct in that a slower-moving vehicle will take longer to travel the same distance than a faster-moving vehicle. But the longer time is precisely why it will be easier, or at most, equally “easy,” for the driver of that vehicle to come to a complete stop before the stop bar once he sees the signal change from green to yellow.

      • James Walker

        For Amy and Dan. Virginia rules require that the yellow intervals meet the Institute of Transportation Engineers calculations to be sufficiently long so that drivers who are at the decision point when the yellow starts have enough time to stop safely OR make the turn. As of January 2013, the times were fixed for straight through movements and the violation rates for that action dropped drastically.

        The yellows are NOT adequately long for turning movements and this is a direct violation of state law at this point. You will hear more about this in the near future.

        At a great many intersections, the profit from straight through violations went away in January 2013 and camera companies plus their for-profit city business partners must now depend on turning movement tickets to safe drivers to make a profit.

        James C. Walker, Life Member-National Motorists Association

    • Dan

      No, to avoid getting a red light ticket, you need to come to a stop at the light. Remember, the decision to stop or not is yours.

  • KB

    I don’t see what all this is about. A yellow light at 3 seconds, 6 seconds or one at 8 seconds. There is always someone that is going to be caught trying to get past that yellow light. Time duration of the light does not matter … there is always going to be a car in that intersection because in todays world yellow means let me sneek through so I don’t have to wait … just to end up waiting at the next light 1/4 mile down the road.
    I am not saying it is right but the story is useless and even if they extend yellows there will be a “yellow sneeker” that will get caught. Or even if you want to take it a step further and side with the “yellow sneeker”, if that person is caught in no mans land and the camera catches them what is the difference between being the 2nd car in line or the 6th car in line … just bad timing in my eyes WHICH is why the comment above erases all this. He explained how an officer reviews each one. I have been caught before and saw the flash go off for the camera but I never received a ticket because they reviewed it and realized I was not at fault.

    • James Walker

      For KB. There are a great many examples where cities added 0.7 to 1.0 seconds to the yellows and got PERMANENT reductions in violations of 60% to 90%. It is a scam for money to set them too short.
      James C. Walker, Life Member-National Motorists Association

  • Chris Woolard

    Just to clarify, “Amy” yellow light dwell formulas and red light light cameras don,t corespond or respond to intersection clearing times and therefore should have little to do with curves, straight lines, or 90 degree right turns. The camera doesn’t take your picture because your in the middle of the intersection during a red light. The process was initiated at the threshold or the white line via induction loops. So your decision Or lack thereof is finlalized at the white line, and has to be 100% focused on an impossible calculation with infinite variables. You have to stop before crossing the white line and Do so before the light turns red.. So do you try to stop on yellow at any distance from the white line or just a certain distance back and at what speed in what weather conditions in what car. If you were crossing the line 1000000000000000000 of a second sooner it would have not triggered the process. As well that amount of driver error would not cause an accident because no other traffic would have entered the intersection yet. So why would that error be leveraged against a citizen? The answer comes back to capitalizing on a person or all persons processing ability. Nobody is that fast and if you are, I would like to see it..

    • Amy

      Processing abilities of drivers is not what I originally commented on. I simply refuted the argument of the gentlemen in the video. Their argument as I understood it was that, according to Physics 101 (talk about condescension), it will take longer to stop a slower-moving vehicle than a faster-moving vehicle. That does not introduce any driver behavior characteristics into their argument. If your argument is that yellow change intervals are not long enough for drivers to make the appropriate decision, then that is something else entirely, and is not limited to only turning vehicles. I would disagree, and state that if the yellow change interval is calculated according to industry standard, and not assigned blindly, then it should be sufficient for both the driver’s perception-reaction time AND the time it takes to stop the vehicle completely. But really, my point is that these guys’ appeal to physics does not hold up in the field of science in which they are purportedly experts.

  • Chris Woolard

    It seems the reoccurring theme for proponents of red light cameras is they say you should stop at all yellow lights. So that means that they themselves stop at “all” yellow lights. That would indicate they somehow manage to stop at any approach distance or speed even if the light turns yellow as they are at the threshold but have not yet crossed. That in turn would mean they are actually stopping on green to keep from crossing on yellow which is impeding traffic and defeats the purpose of the light as flow control. If you don’t use that method the your left with t

    • steve

      I’m one of those proponents and I’ve had a somewhat different perception – that our underlying theme is that yellow means stop for the light if you can do so safely and without entering the intersection. I’ve never heard anyone advocating slamming on brakes and/or careening into an intersection.

  • Amy

    Actually, the yellow time calculation is a function of perception-reaction time PLUS the calculated time that a vehicle can reasonably stop (taking into account speed of the vehicle, grade of the roadway, braking forces, and acceleration due to gravity). Therefore, if this method of calculating the yellow change interval has been performed correctly, the distance at which the driver can first see the signal turn yellow gives a vehicle traveling at the 85th percentile speed, or the speed limit, whichever is higher, a reasonable chance to comfortably stop before the stop bar. If the calcuations for this amount of time are performed assuming a higher speed (of a vehicle traveling straight through the intersection), as opposed to the lower speed at which a turning vehicle would presumably be operating, then that amount of time (yellow change interval) would need to be longer for the vehicle operating at the higher speed, not the other way around. Assuming the stop bar is located at the exact same distance away from the turning vehicle, that turning vehicle’s driver has a BETTER chance of stopping his vehicle before the stop bar,because he has to apply less braking pressure to stop.

    A slower vehicle is always easier to stop than an equal-in-mass faster vehicle, all other factors being equal. THIS is Physics 101, not whatever these guys are postulating.

    • James Walker

      Actually, Amy, the perception/reaction time is almost always calculated at 1.0 seconds which is the mean time required. Thus about 50% of the drivers take longer than 1.0 seconds for perception/reaction time. To accommodate 85% of the drivers, the perception/reaction time must be at least 1.37 seconds and earlier this year Florida mandated 1.4.
      James C. Walker, Life Member-National Motorists Association

    • James Walker

      For Amy. IF the straight through driver and the turning driver hit the decision line for the 85th percentile speed at the same time and the yellow is correct for straight through (true since January 2013), the straight through driver will just clear the stop line at the very last part of the yellow. The turning driver will NOT make it in time, the light will go red when they are about one or two car lengths away. They have the choice to spike the brakes or get a ticket.
      James C. Walker, Life Member-National Motorists Association

  • Chris Woolard

    That’s the point, the formula Is based on set variables that would apply in most situations where (perception) and (reasonable) are aceptible forms of measurement! They however cannot and should not be used when the measurement is calculated at speeds of less than a millisecond, as preformed by a red light camera. There is simply no need to be that accurate when negotiating a traffic light.. Using the formula for traffic flow without a camera is fine but a person would have to calculate at the speed of the algorithmic process within the camera system to eliminate even the most microscopic timing error to accurately and consistently avoid a ticket even though that would not be required to safely cross the intersection. So you have to ask yourself why would a person be held to such accuracy that it can only be measured by a machine and that reaction being so minute that it’s beyound our human abilities.

    • Amy

      Well, if it makes a difference to you, Virginia state law requires that cameras only be activated 0.5 seconds after the signal has turned red. So you can actually underestimate your driving distance (assuming you’re driving at 45 mph) during the yellow change interval by about 32 feet and still make it into the intersection before the camera activates.

  • Terri

    Channel 3 there are a couple of lights that I have reported to the city of Norfolk but nothing has been done. The light at the corner of Princess Anne and Tidewater going west it does not change like it should. This causes people to run the light. The light at the corner of Tidewater and Linwood, the red light is too long and you cannot turn on red. People turn red anyway and if you check court records a lot of people get tickets for running the light. Just my two cents.

  • B

    Prior to automated enforcement red light running problems were fixed by adding yellow signal time. This means any formula errors back in 1965 were irrelevant.

    When camera enforcement came about ITE changed their standards such that all red+yellow had to be certain amount of time. This allowed for the yellow signal time to be adjusted downward to minimum values. Also the recommendation for correcting red light running problems was changed to ‘use enforcement’.

    See the congressional report written by Dick Armey’s staff some years back. It can be found on the websites of thenewspaper (a driving politics blog) and that of the national motorists association. I would give direct links but I don’t know the policies here of posting urls, so I’ll just avoid it.

    • James Walker

      Correct, B. The clearance interval was split into a yellow plus an all red. BOTH are supposed to be calculated according to the actual traffic flow speeds and the width of the intersection — but the split left LOTS of room for deliberate abuses. Suppose the total interval should be 5.0 seconds and the yellow should be 4.0 with the all red at 1.0. Set that way, there are very few violations and the crash risk is very low.

      BUT, set it with a yellow of 3.2 and an all red of 1.8 = 5.0 total. The crash risk remains very low, but there will be a HIGH rate of violations. Set up a camera and watch the money roll in.

      The most common scam is to set the yellow for a posted speed limit that is about 10 mph below the actual 85th percentile speeds. That gives a yellow about 0.7 to 0.8 seconds too short. Camera companies and their predatory for-profit city business partners know about 60% of the violations in that location will be in the first 0.5 seconds. It a vicious racket that should be banned by law.

      The website thenewspaper.com is run by a former Dick Armey aide and exposes many of these scams.

      James C. Walker, Life Member-National Motorists Association

  • Dave Lyons

    I’ll just say this much:

    To proceed through an intersection with a green light is the ONLY, let me repeat, *ONLY* legal action.

    In other words, if the light is yellow, or red, you are in violation of the law.

    Period.

    Obey the law, and you don’t have to worry about the cameras, or the other nut drivers out there who might hit you because you blew the intersection.

    • James Walker

      For Dave Lyons:

      In almost every state, this is false.

      Entering on yellow is perfectly legal AND if you are beyond the reasonable braking point when the light goes from green to yellow – it is absolutely wrong and in some states illegal to panic brake trying to stop.

      James C. Walker, Life Member-National Motorists Association

    • steve

      Actually, there’s no law against proceeding through a yellow light. Whether one should stop for yellow depends whether they can do it safely and without ending up in the intersection… slamming on brakes and careening into an intersection is never a good idea and the law doesn’t require it.

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