Rational Safety or Driver Child-Proofing?
Reader Kent from New Zealand writes in with news of a new safety technology called “Raptor,” meant to sheathe road-side poles.
Many road deaths followed collisions with a tree or pole, James said, and tests had shown that a passenger compartment crush reduced from 500mm, when hitting an unwrapped pole, to 10mm when hitting a pole sheathed with a Raptor.
My first thought is: How soon until advertising is sold on those? Second thought is I have no problem with deploying those on high-speed roads, in which case there probably shouldn’t be poles or trees close to the road in the first place, but putting them up on lower speed roads, apart from being aesthetically unpleasant (I mean, really, do you want your town’s streets looking like the pit entrance at Talladega?), is just further child-proofing that will only encourage more bad behavior from drivers who should know better.
Trees tend to be uniformly defined as a hazard by road engineers, but another way of thinking about them is as a safety device: They protect pedestrians from wayward vehicles, and encourage slower speeds (lower speeds also reduce passenger compartment crush) by drivers. As always in these cases I refer to the work of Eric Dumbaugh:
Eric Dumbaugh, assistant professor of landscape architecture and urban planning at Texas A & M University, made a strong case that traffic engineers sometimes fail to understand the implications of their own accident data.
He presented some forceful statistics showing that while American rates of highway fatalities have fallen significantly over the past 30 years or so, they haven’t fallen as fast as the rates in other advanced countries. “We’ve fallen behind our first-world design peers.”
The problem is that American road builders’ model for a safe road is an Interstate highway – with limited access, wide lanes, and few turning options. The result is that engineers try to turn every road into an Interstate, with serious effects on aesthetics, and on safety too.
Dumbaugh argued that there is another model for a safe road, and that is the local street that is “dangerous by design.” Its hazards – curbside trees, for instance – are obvious. They force drivers to slow down, and that makes for greater safety.
He showed a slide of a stretch of road in Florida he had studied as part of a larger investigation of car crash sites. This particular stretch is lined by trees – the obstacle traffic engineers love to hate – on not just one but both sides. But it was clear from the picture that this is part of a real neighborhood – the kind of area where a driver instinctively slows down.
The road runs through the campus of Stetson University, an area with college students, dorms, and bars. And yet during the five year period his study covered, Dumbaugh said, there was not a single fatal crash there.
This entry was posted on Tuesday, June 8th, 2010 at 8:29 am and is filed under Traffic safety. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.