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Denver Must Prove Red-Light Cameras Improve Safety
An anonymous reader writes "An audit of accidents at Denver intersections where red light cameras were installed versus increasing the length of the yellow light shows little difference in the results. In a case of putting the public ahead of the corporation, the Denver auditor is recommending canceling the red light camera program unless the city can prove a public-safety benefit." I hope that private citizens offering analysis or recommendations are treated fairly.
...reading some years back that the Red Light camera companies had specific language in the contracts that restricted the length of yellow lights.
A cynical person might think they wanted people running red lights. But I'm not...oh, fuck it. I am cynical.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
I used to think the intersection camera were a good idea. However, I changed my mind once a I listened to a local police chief explain that in his city traffic accidents had actually risen at the intersections where the cameras were in use. Folks would brake suddenly when they saw the camera causing the vehicle behind them to rear-end them. Once he said that I knew he was right. People would do that.
The cameras are a good idea in theory, but the real-world unintended consequences are too costly.
Long yellows to give everyone a chance to stop, and red light cameras to catch the bastards who don't take that chance.
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In many states drivers are taught to enter the intersection to take a left turn, and it's legal.
I have seen several studies showing a very distinct link between length of the yellow and safety. This study shows that increasing the length of the yellow decreases red light violations and this article references several studies that show that this effect does not diminsh with time. So, your gut is wrong on this one (although I understand why you would suspect that to be the case).
The truth is that all men having power ought to be mistrusted. James Madison
You should never be so close to the car in front of you that this happens. If you are, you absolutely are at fault.
"Oh no, the light is now red, there is intersecting traffic"
no cross traffic should enter the intersection until the way is clear.
Green != Go
Green = precede if clear
Also worth reading this - Oregon DOT Recommendations: http://www.oregon.gov/ODOT/HWY/TRAFFIC-ROADWAY/docs/pdf/ODOT_yellow_red_clear_policy_A1.pdf?ga=t
The 3 to 6 recommendation is based on some general assumptions and characteristics. It's still a mathematical equation. Also, here's a few c/p from the parent's references that are relevant (including the statement that yellow duration is commonly limited by control manufacturers and the shortfall is made up during a red phase):
The calculation requires values for perception/reaction time of the driver, deceleration rate for stopping vehicle, vehicle speed, approach grade (uphill, downhill), intersection width and design vehicle length. The standard value used for the perception and reaction time of drivers approaching a signalized intersection is 1.0 sec.
The Highway Design Handbook for Older Drivers and Pedestrians concludes that the 1.0-sec. reaction time is appropriate for both older and younger drivers, but that the use of a 1.5-sec. reaction time “is well justified when engineering judgment determines a special need to take older drivers’ diminished capabilities into account.”
The MUTCD (Manual of Uniform Traffic Control Devices) indicates that the yellow change interval should be set within the range of 3 to 6 sec. and many signal controller units will not permit settings outside of this range. If the phase change interval needs to be near the top of this range or beyond, the additional time is sometimes provided as part of a red clearance
interval.
When it comes to safety, we should never play the blame game. It does not matter who is at fault, what matters is people being safe. The fact is that we need to do what we can to ensure safety. People will do what people always do -- that is they will do stuipd and dangerous things. I work in industrial automation designing machines. Whenever we design something, we do our best to think of every stuipd thing that the machine operator will try to do. We look at ways they might try to reach into a machine to grab a part, or places where they may try to get too close to a moving machine and every other idiotic thing they try to do.. Then we try to come up with some way to ensure that they can't do those things or at least that the machine will shut off if they do. Yes, it is stupid for them to do these things, yes it may be their "fault" if they get injured, but the fact is that people do these things anyways and we have a responsibility to try and ensure that they keep safe. I never want to see anyone get injured on a machine that I designed. This situation with traffic cameras is no different. People should not be following the car in front of them too closely, but they do. If using cameras causes people to rear end eachother more often (regardless of who is at fault), then we should not be using them.