^ Red light cameras have their serious failings. More in the way they are set up, and the general synchronisation of the traffic lights at a given intersection, but there are a number of other problems as well.
Let's look at the set up of the traffic lights generally first.
I will use Nepean Highway as an example because: 1) I have been a regular user of it for over 30 years; 2) It is an 80 kmh road with many intersections with 60 kmh cross roads; 3) It is a main arterial road, carrying a very large number of cars 24/7.
The government authorities have managed to synchronise the lights for significant distances of this road between Elsternwick Junction and Mentone approximately twice in this 30+ years (once for about 6-12 months in the late 1980s, IIRC; and for about the last 12 months or so). This represents a scandalous neglect of duty IMNSHO. In Brisbane in my far-distant youth, the traffic lights in Ann St were synchronised to 28 mph, and if one travelled at this speed, one could travel from North Quay to Fortitude Valley through the city CBD without stopping. Of course, it didn't take us young hooligans long to work out that if they were synchronised at 28 mph, they were also synchronised at 56 mph ...
. If it was possible to do this in Brisbane then, surely we can manage it now, some 50 years later! Traffic light synchronisation means that cars and heavy vehicles do not have to stop from, and re-accelerate to, high speeds regularly.
To stop from, and re-accelerate to, 80 kmh costs about $1 for an 'average' car. It is around $4 for a 5 tonne truck, and much more than this for a heavy truck (big semi-trailer, B-Double, etc). The communal cost of this stop/start regime on just the Nepean Highway is enormous. The indirect and externalised costs (pollution, maintenance, repairs) adds greatly to these direct costs.
When one has turns from an 80 kmh road into a 60 kmh road, one has to make proper allowance for the change in speed, and also for the rate of approach to the turn lights in slip lanes. The relevant intersections of cross-roads with the Nepean Highway make very little, if any allowance for these factors. The light sequences also vary from intersection to intersection, further confusing drivers travelling at high speed. This is stupid, inexcusable and disastrous in practice.
Further, when one is turning, there is a point at which one has to remove focus from the light and concentrate on the turn - vehicle in front? pedestrian crossing against the lights? on-coming traffic that is not going to stop? etc, etc. The light subtends a tiny angle at one's eyes, and is in one's peripheral vision as well. The
Monash University Study at p.45 found that a survey including rally drivers only had around a cumulative 40% of drivers with a reaction time of 1.0s or less to level crossing lights at night. This dropped to around 20% to the same stimulus during daylight. This is directly analogous to reaction to traffic signals when those signals are directly in front of the driver, but not to turn signals which are not.
The mean reaction time was 1.16s with a std, dev. of 0.35s (night), and 1.77s, s.d. 0.84s (day). This argues strongly against applying a 0.5s rule to red light cameras, particularly on high speed roads (i.e. 80 kmh and above); and more particularly to turn signals off those roads onto suburban streets with a speed limit of 60 kmh.
Other government advertising (TAC, various police forces, etc) advertise that average reaction time is between 1.5s and 2s. Why then is there a relatively uniform 0.5s time applied to red light cameras? More revenue is one possible explanation ...
If the traffic light sequence has to be modified to accommodate longer periods between one direction light going to red and another direction going to green to ensure safety, so be it. Synchronising the through lights properly would make up for the small inconvenience of the latter, IMNSHO.
Just a few thoughts, FWIW ...
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