Making Things Less Dangerous by Making Things Feel More Dangerous

How do you make things less dangerous?  Sometimes, paradoxically, it's by making things feel more dangerous.

Let me explain, with the help of excerpts from three articles I recently read.  First, from Citified, which reported on a recent study that showed that bike-share riders had fewer accidents than regular riders:

What they found out was that, despite some factors that some experts saw as making bikeshare use more risky — bikeshare users are less likely to be experienced riders, to know local streets and to wear helmets, for instance — other offsetting factors made them less likely to get into accidents or sustain injuries...One of the chief offsetting factors is the design of the bikes themselves. "The wide body and sturdy build of the bicycle has the feel of a heavy mountain bike, and this design may reduce the degree to which dangerous maneuvers are made on these bicycles," Martin said in a news release. "This would imply that the bicycle design is influencing the bicyclist to act in a safer way." Members of the focus groups also said they cited this as a key factor and said they observed bikeshare riders behaving more cautiously as a result.

Janette Sadik-Khan recently wrote in New York Magazine about the mass introduction of bike lanes and related bicycle-serving infrastructure in New York City:
The anti-laners had tried to establish their own traffic-safety narrative in a letter to the New York Times. “When new bike lanes force the same volume of cars and trucks into fewer and narrower traffic lanes, the potential for accidents between cars, trucks and pedestrians goes up rather than down,” they wrote. “At Prospect Park West in Brooklyn ... our eyewitness reports show collisions of one sort or another to be on pace to be triple the former annual rates.”  While their eyewitness reports painted a dismal picture, statistics told a far different story. Russo clicked through the presentation as reporters lurked around the auditorium. Speeding on the corridor — the original impetus behind the project — bottomed out, from 74 percent of cars on Prospect Park West speeding before to just 20 percent after. Sidewalk bike riding dropped from 46 percent of riders on the sidewalk before the project to just 4 percent after. The number of crashes actually resulting in injuries dropped 63 percent. Traffic volumes and driving time remained unchanged.

Finally, from the profile in Pennsylvania Gazette of Sam Schwartz, aka Gridlock Sam:
A second factor pushed the calculus even further toward building a high-capacity modern bridge: standard 12-foot-wide lanes would be safer than the Williamsburg Bridge’s 9-foot-wide ones. That was an all but universally accepted truth among traffic engineers. Except, when Schwartz mapped three years’ worth of accidents on the bridge, the data showed something counterintuitive: the bridge’s safest sections were where the lanes shrank to their narrowest points, near the support towers. Perhaps because they caused drivers to behave more cautiously, “grossly substandard lanes seemed to be the safest of all.”
Transportation infrastructure is designed by engineers using computer models but is consumed by finite and fallible humans.  Where things feel more dangerous, humans take extra precaution, and their safer behavior more than compensates for the extra danger.  This is the theory behind "naked streets": less lines and less signage means I have to slow down and figure things out, more than compensating for the reduction in physical helps.

It's an interesting premise...which will get flipped on its head once humans stop driving and start riding self-driving vehicles.  However many years or decades out that is, let's be careful out there.  Really.
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