In your previous post “Department of Correlation” you lament that traffic safety engineers believe that motor vehicles and pedestrians can co-exist on low speed, low volume residential streets where on-street parking is restricted/prohibited. You note that there is an inverse relationship between parking and vehicle speeds and that parking acts as a “buffer” between cars and pedestrians — implying that that is the key to pedestrian safety.

As I noted in the comments to that post, new urbanists have been making this claim for quite some time now. It is interesting how if a group makes a statement enough times that many people will start to believe it — even with no evidence to support it. Given how hard you work to cite evidence and promote science based conclusions I am surprised that you have bought into this so readily.

Now, in your Slate column on Children Playing signs you reference “peer reviewed science” to support your claim that increase traffic speeds increase risk of injuries to children. Yet, if you read the actual study you cited it doesn’t really say that. The actual study can be found here: http://ukpmc.ac.uk/backend/ptpmcrender.cgi?accid=PMC2548498&blobtype=pdf). The key findings of the study are:

a strong association between increasing risk of injury of child pedestrians and increasing traffic volume

High density of curb parking was also associated with greatly increased risk of injury

Transport policies that reduce traffic volumes in urban areas could substantially reduce rates of injury ofchild pedestrians

Restricting curb parking at crossing points may also be effective at reducing risk

Note that nowhere in the key findings does it associate reduced speed with reduced injury risk as you claim. In fact, it found a non-linear relationship between speed and injury risk.

The ironic thing about the study is that it confirms the quote in your previous post that you took exception to. The study pretty much says that low volume, low speed residential streets with restricted or prohibited on-street parking can help pedestrians and motorists co-exist. Chalk one up for the traffic safety engineers.

I don’t know if these signs are being phased out or if I just stopped noticing them (they’re kind of part of the scenery, you know…).

Now, of course, it is time to apply his argument to cycling. Everything that he has to say against “Children at play” signs applies equally to sharrows. And for the exact same reasons. They have no benefit and are a meaningless “feel good” response to political demands to “do something.”

The rights of motorists to assume they arrived significantly sooner by racing TCD to TCD and/or not stopping for signs or before their RoRs shall not be infringed.

“I been driving like this my whole life and I’ve never crashed”.

That must be the same rationale for waiting for a walk signal (in a 25 zone with traffic going by at ~40) with toes hanging over the curb.

There seems to be no method to convince most motorists that -they- are a hazard to themselves and others and/or that driving is a dangerous activity.

We’ve also just fitted a zebra crossing, a pedestrian crossing where cars are required to stop for pedestrians. This has had the most benefit for traffic calming, though having been only in for a couple months, not everyone stops. It’s as if after driving a route for a certain number of years, drivers are either unable or unwilling to accept any changes in rights of way or priority. Has anyone done studies in that -the ability of drivers and others to adapt to change?