COMMENT & ANALYSIS / SHORT: Flashing amber traffic traffic lights are to be “rolled out across Dublin city” it seems basically because Dublin isn’t ready to ask turning motorists to wait for people cycling.
We recently covered Dutch-style vs Dublin-style protected junctions, which uses flashing amber directional traffic lights. Today, Dublin City Council tweeted: “Flashing amber arrows for left & right turning vehicles are now being rolled out across Dublin city” (video below).
There’s a few problems with this:
1. Flashing amber left turning signals don’t work at pedestrian crossings
If you have regularly used pedestrian crossing which include flashing amber left turns for motorists, at the same time as the green man is shown, you likely know this design does not work. Everyone might not agree but the feeling of being on edge when using such crossings is my experience of such and I lost count of how many times I had to explain to motorists that the green man was still shown when they tried to drive into me.
Maybe traffic engineers think otherwise, but this design doesn’t work, at least not at large junction. Even beyond safety, the design fails on attractiveness. If Dublin City Council is serious about designing for all ages and abilities, it has to realise it is falling far short of that.
Maybe the design will make a few people happier to be able to say that they are in the right when motorists turn across them when they are trying to cycle straight on. But the reality is the legality of who should have yielded their right of way will still be argued out in any contentious cases.
2. Similar cycle lane designs in London are linked to deaths
An increase in cycling deaths is in London was liked to designs where cycle paths went inside a left turning lane and motorists got a green light at the same time as people cycling got a green light. I’ve referenced this before but it seems like it’s worth referencing again:
“At first, Deegan said, the cycling design standards used in London were Dainish-like but they found that drivers turning left behaved poorly swinging left on front of people cycling. He said that there were “quite a lot of fatalities” and it was at that point that more Dutch-like principals were adopted.”
Given what happens at pedestrian crossings, it seems unlikely that the addition of a flashing amber traffic light will change much.
Since a spike in deaths linked with left turning vehicles London has also done a huge amount of work in truck safety. Ireland has done some of this, but is still behind London in terms of regulations on direct vision trucks.
3. Dutch guidance says don’t do it
Traffic design guidance in The Netherlands is to phase out similar signals where possable. Warning signs and mirrors are used where design remains (see below) but these do not stop collisions.
Best practice is to hold left turning traffic on red while people cycling straight have a green light — it’s what’s safer.
Flashing amber arrows for left & right turning vehicles are now being rolled out across Dublin city. This will reinforce the existing road regulations, requiring turning vehicles to give way to cyclists proceeding straight ahead at a junction. https://t.co/XD6Whmw0zf#cycledublin pic.twitter.com/5n3L9pb5W4
— Dublin City Council (@DubCityCouncil) April 7, 2021
Examples of Dutch warning signs (let op! = watch out! Or look out) and mirrors: