Dun Laoghaire Traffic & Commuting Chat

Homesick Alien

https://www.boards.ie/discussion/comment/123783746#Comment_123783746

Roundabouts are stressful for cyclists, especially children. Because motorists rarely signal when leaving a roundabout they never know when to enter the roundabout and meanwhile a queue of impatient motorists builds up behind. That's my experience of cycling with my kids anyway. At least at a junction you know when you have the green light.

Blut2

https://www.boards.ie/discussion/comment/123784242#Comment_123784242

They're wrong so. The academic literature is fairly clear on this:

"information showing that at the lower 20-mph speed of most roundabouts, the chance of a
pedestrian being killed if hit by a vehicle is 15%. On the other hand, at conventional
intersections where the speeds are typically 30 to 40 mph the chances of being killed if
hit by a vehicle range from 45% to 85% "

Pedestrian safety is also an issue of perceived vs. real risks. Even though
pedestrian safety at roundabouts seems to be high (based on international experience and
limited U.S. experience) many pedestrians do not perceive roundabouts to be safe. Yet,
compared to intersections controlled by two-way stop signs, roundabouts improve
pedestrian safety, especially for crossing major streets. Approach speeds are lower and
unexpected right or left-turning movements do not exist at roundabouts."

And for car on car collisions too:

"The circulatory vehicle movements at roundabouts eliminate
or drastically reduce the critical conflicts resulting from red light running, left-turns
against opposing traffic, right-angle conflicts at corners, and rear-end collisions. As a
result roundabouts significantly reduce vehicular crashes.

According to Persaud2, modern roundabouts are safer than other methods of
intersection traffic control. After examining 24 intersections that were converted to
roundabouts in eight states in a variety of urban, suburban and rural settings, he
concluded that roundabouts reduced all vehicular crashes by 39 percent and injury
crashes by 76 percent. He estimated reductions in the numbers of fatal and incapacitating
injury crashes to be about 90 percent."

VinLieger

https://www.boards.ie/discussion/comment/123784609#Comment_123784609

It is ironic that the states seem to finally be embracing roundabouts but we are for nonsensical reasons moving away from them.